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Regulation of water yield and quality in British Columbia through forest management Golding, Douglas Lawrence 1968

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REGULATION OF WATER YIELD AND QUALITY IN BRITISH COLUMBIA THROUGH FOREST MANAGEMENT  DOUGLAS LAWRENCE GOLDING BcScsFo, University of New Brunswick, 1953 M.SoFo, Purdue University, I96I  A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY i n the Department of FORESTRY We accept this thesis as conforming to the required standard  THE UNIVERSITY OF BRITISH COLUMBIA January, I968  In  presenting  for  an a d v a n c e d  that  the I  thesis  for  Department  shall  further  agree  at  in p a r t i a l the  make  it  that  freely  or  representatives.  his  of  my w r i t t e n  this  thesis  for  permission.  Department The U n i v e r s i t y o f B r i t i s h V a n c o u v e r 8, C a n a d a  Columbia  of  for  be g r a n t e d It  is  financial  of  British  available  permission  p u r p o s e s may  by  fulfilment  University  scholarly  publication  without  thesis  degree  Library  study.  or  this  for  the  Columbia,  I  reference  and  extensive by  the  requirements  copying of  this  Head o f my  understood that gain  agree  shall  not  be  copying allowed  i  ABSTRACT  The  economy  water-diversion the  water  water  resources  on  tribution, that A  of  the  mended  with  that  The  ments  was  of  may  British  reference  Technology,  water  the  for  i n i t i a t i n g  The  the  interest  water  shed-management and  of  resources regions  Columbia Mountains)  Because  willing  the  the  on the  i n -  d i s shown of  related  to  water.  to  of  was  recom-  and  that  water-  Training  British  Columbia.  of  the water  some d e g r e e  were  climatic  the  examined  (Coastal,  Peace  governfederal adminis-  should  water-resource  of  were  It  government  management  province  basis  role  federal on  of  management  Service  present  1  forego  water  and p r o v i n c i a l  passive  action  designated  the  has  quality  and  Forest  Canada s  the  comprehensive  were on  the  future,  of  and  increased  federal  reason  be  at  be  the  for  should  staff  between  responsibility provinces  requiring temporal  management.  University  the  in  forest  of  the  resources.  dependent  Research  presented  recent  importance,  and  regime,  and  for  rights  to  emphasis  as  i t s  properly,  problems  greater  inadequate  the  and  receive  tration  and  was  f i e l d  suggested  of  spatial  y i e l d ,  Service  jurisdiction  America i s  to  Columbia.  administration,  of  i t s  according  influenced.  research  i n  assume  managed  be  the  North Because  resource,  government i s  be  Forest  Institute  division  the  such  particular  shed management School,  i n  western  must  factors  of  Columbia but,  Columbia.  influences  review  B.C.  much o f  of  these  management  British  province  amount  Legislation, discussed  only  British  management  comprehensive  watershed  of the  a n d how  forest  not  proposals,  resources  formation  of  development,  of  provincial  resource. and  four  River,  factors,  water  water-  Interior, needs,  ii and flood and erosion potential.  Forest-management was related to the  objectives of watershed management i n each region.  One objective of  watershed management i n the Interior Region i s increasing water supplies. Tree Farm License No. 9» i n the Okanagan Valley was used to demonstrate forest-management effects on water yield.  Yield could be increased five  per cent by substituting for the present forest management one based on financial rotations and consideration of water as an important secondary product. Statistical calibration of Windermere and Sinclair Greeks i n the East Kootenays was presented, and the effect of logging on streamflow from Watching Greek near Kamloops was analysed graphically.  Water balance  and other studies were presented for Terrace Greek watershed on Tree Farm License Noo 9»  Other watershed research i n British Columbia was reviewed  and research needs discussed.  A comprehensive research program was  recommended, to begin with intensely-instrumented research watersheds i h the Coastal and Interior Regions. A rational mathematical rainfall-interception model was developed using forest-stand variables, most of which can be measured on aerial photos, and data from interception studies carried out i n British Columbia and the United States.  iii  ACKNOWLEDGEMENTS The writer wishes to acknowledge the guidance of Dr. P. G. Haddock, Dr. J . H. G. Smith, and Prof. Wo W. Jeffrey during the course of this study, and to thank Prof. T. L. Coulthard, Prof. J. deVries, and Dr. B. G. Griffith for their assistance and review of the thesis. Acknowledgement i s also made of assistance given by S. M. Simpson Limited, Kelowna, B.C<>; Mr. P. N. Sprout, Soil Survey Branch, B.C Department of Agriculture, Kelowna; and Mr. R« J» Talbot, District Engineer, Water Rights Branch, B.C. Water Resources Service, Kelowna, BoC The author i s grateful for the use of f i l e s of the B.C. Water Resources Service and maps produced by the Department of Geography, University of British Columbia. financial support was provided by the National Research Council, VanDusen Graduate Fellowship i n Forestry, and Faculty of Forestry Graduate Fellowship.  iv TABLE  O F CONTENTS  Page ABSTRACT  i  ACKNOWLEDGEMENTS TABLE  OF  .  .  CONTENTS  O F TABLES  LIST  O F FIGURES  L I S T  OF  •  .  .  O  . o  .  .  .  .  o o  i i i o  o  o  o  0  »  o  o  .  .  .  o  e  o  o  o  o  .  .  .  iv  .xvii  LIST  MAPS  .  . . xix •  •  .  •  •  .  •  •  .  .  <  »  .  o  .  .  .  .  o  .  o  o  o  e  o  .  o  o  xxi  Chapter l o  II.  INTRODUCTION  FORESTS X •  e  .  .  .  .  e  o  o  .  AND T H E HTDROLOGICAL o  «  *  «  e  o  o  Annual  Rainfall  Effect  o f Wind  Evaporation  «  o  .  e  o  o  o  .  e  «  .  .  »  o  o  »  o  o  o  «  1  . o  o  o  o  o  o  0  o  «  e  *  e  o  c  «  o  k ^  •  .  .  .  .  .  with  season  Variation  with  stand  O  O  FOg d r i p  0  .  O  .  .  .  .  .  »  •  •  •  •  •  •  •  •  •  9  •  species  O  .  9  .  Variation  SteillflOW  7  Rain  between  loss  «  k  Variation  Water  .  CYCLE  o f Falling  Interception  .  O  .  .  .  .  .  density  O  0  1^  O  0  O  .  .  0  .  .  .  andage  O  0  .  O  0  O  0  .  0  .  0  . .  0  0  .  .  .  .  .  .  o  o  o  o  o  0  0  0  0  .  0  .  .  .  . o  16 1?  19 21 23  V  Chapter  2o  Page Evaporation from Foliage . . . . . . . . . . . . . . . .  24  Moisture Storage i n Vegetation . „  25  Condensation . . « .  25  . . « o e « e o . . « o o . « . . . . » » . » . . » .  26  Interception . • • » « . « « o « . » » « o « . » . . . »  26  Accumulation  29  Snow  . . . . . . . . .  In the open  30  In the forest  •  31  Evaporation from Snow Melting of Snow 3.  Evapotranspiration  33  o . . o . . . . . . . . . . . . . . . .  37  . . . . . . . . .  40  Methods of Measurement . . .  ... . . . . . . . . .  40  Tent method  40  Quick-weighing method  41  Sap velocity method  42  Energy budget method Eddy fluctuation method  . . . . . . . . . . . . . . . .  43 44  Soil moisture budget  44  Potted plant method  46  Lysimeters . o o . o . o . o e o o e . . . . . . . .  46  Results of Investigations . . . . . . . . . . 4. Streamflow  ..  Annual Discharge  48  . . . . . . . . . . . . . . .  52 52  vi Chapter  Page Flow Regime . . . » „ „ . . . . . . . .  57  Wagon Wheel Gap, Colorado  •  San Gabriel River, California Coweeta, North Carolina  57 . . . . . . . .  58  H.J. Andrews Experimental Forest, Oregon  58  Fernow Experimental Forest, West Virginia  59  Fraser Experimental Forest, Colorado  59  Shackham Brook, Central New York  60  . . .  60  Erosion  62  Erosion Studies Erosion Hazard Ratings  64 . . . . . . . . . .  ..  Erosion Control 6.  Water Quality  Logging  66 71 74  Effect of Logging on Water Quality  ?.  57  Pine Tree Branch, Tennessee  Snowmelt and Water Yield 5.  57  77 .....  77  Stream channels  80  Roads  80  Fire  85  Forests and Fish  8?  Water Yield and Regime Debris i n Channels  88 • •  90  Chapter  Page Water  III.  Temperatures  ADMINISTRATION 1.  OF  WATER  90  RESOURCES  Jurisdiction British  92  North  Relevant  America section  Interpretation 2.  92  Evolution  of  Water  Act of  .  .  92  the .  .  act  .  92  .  .  93  Policy  93  Canada  93  Early  conferences  Conservation  Commission  Reconstruction Resources Canadian  94  for  Tomorrow  Council  Fields  Water  Resources  of  .  94 95  Conference  Resource Premiers'  96  Ministers  96  Conference  97  ,  99  C  Service Water  99 Resource  .  .  .  .  .  .  .  .  .  100 101  Agencies  Agencies  Discussion  .  Agencies  Federal-Provincial  4.  .  98  A d m i n i s t e r i n g The  Provincial  Other  .  Act  acts  Federal  .  98  Water  Agencies  .  Columbia  Gold  3.  .  Conference  Federal-Provincial British  .  103 and I n t e r n a t i o n a l  Agencies  .  .  .  .  .  104 106 107  r  Page  Chapter Problems  o o . . . o o o o » o . e » o  B o N o A . Act  o o o e .  o o o o o o o  Provincial attitudes . o Federal attitudes  Recommendations  o o o o o o o  . .. o o o o o o  o o ..  00000000  '. . o o o •  00000000  .0000  Federal level  0  9  Provlnoial level , 0 0 0 Data collection IV.  o o e • >o o  00000000  Administration « o . « c o Data collection  o  O  O  0  0  0  0  o o 0 o. 0  . . ..  WATER RESOURCES OF BRITISH COLUMBIA lo  Climatic Regions  .•  Precipitation Amount  000000  » o ... . o  00000000  o o o o o o o o o  . . . 0 . 0  Seasonal distribution Extremes  o o o o o o o  000000000.0000 000000000000  Intensity  Relation to watershed management o Potential Evapotranspiratlon . 0 0 0 0 0 «. e 0 . o  Actual Evapotranspiratlon  Moisture Deficit . . . . . . » .  0 0 . 0 0 0 0 0 0 0 0  Runoff Regions 3©  Water Needs  «  •  *  '  «  *  o  9  «  o  «  9  ©  «  Q  *  O •  9  •  o  •  ©  ©  O  ©  •  0  ©  0  ©  O  9  O  »  0  •  ix Chapter 4.  P a  Watershed Management Regions Coastal Region  135  . . . . . .  . . . . . 135  Columbia Mountain Region  135  Interior Region . . . . . . . . . .  136  5. Water Diversion Schemes  . . . . . . . . . . . .  136  NAWAPA  137  Location  •  •  138  Conception  139  Engineering  140  National water policy  141  Other Diversion Schemes Kootenai River diversion  V.  Q  135  . . . . . . . . . . . . . .  Peace River Region  g  146 . . . . .  146  Clearwater-Red Deer River diversion  147  The GRAND canal  1*8  FOREST MANAGEMENT AND THE WATER RESOURCE IN BRITISH COLUMBIA .  149  1. Watershed Management and Legislation  149  Establishing the Forest Service  ..  Forest Reserves  •  The Royal Commission of 1955-1956 The Forest Act of British Columbia 2. Erosion Examples of Erosion . »  149 150  < > 153 .  155 158 159  X  Chapter  Page Brodie Creek flood Giveout Creek slide  159 162  ...  164  Unnamed Creek flood  165  River Bank Erosion Salmon River - Falkland area  165  Shuswap River - Mabel Lake area  166  Elk River - Fernie area  166  Sedimentation  I67  Large-Scale Earth Movement Hope-Princeton slide  . . . . . . . .....  I69 I69  Ocean Falls snow slide  170  Granduc avalanche  170  Lillooet slide  170  Ramsay Arm slide  171  Indian Arm slide . . . . . . . . .  171  Revelstoke avalanche . . . . . . . . . . . . . . . .  172 172  Recognition of the Problem of Erosion Administrative Measures  ..  . . . . .  174  Training of Forest Service personnel  174  Forest Service staffing  175  Protective clauses i n timber-sale contracts  ....  178  Enforcement of contract conditions .  179  Timber harvest subsidies  180  x i  Chapter  P a  Logging  Measures  to  Reduce  Erosion •  method  Logging  method  Road  Construction  .  .  .  .  .  182  .  183 183  Methods  Road  location  Road  construction  and  to  Reduce  design  .  .  .  Erosion .  .  .  189  .  .  .  .  .  .  .  .  189  •  191  Drainage Stream Road  and  193  channels  Drainage  .  Post-logging  Quantity  .  .  .  .  .  .  .  .  Increase  Present  .  .  .  ., measures  Water  forest  forest  .  .  .  .  .  197 198  .  .  .  .  205 .  management  primarily  of  . .  management  water  .  .  .  .  .  .  .  .  .  .  • .  production for  Yields  water  .  .  demand  207 215  .  .  .  .  .  .  .  216  water  218  phreatophytes  Water of  .  Yield  Forest  Timing  .  204  and  of  196  Runoff  management  Timing  195  202  Forest  Control  .  Rating  Total  Unmanaged  .  196  erosion-control  Timing of i n  .  «  Hazard  and  .  ,  Burning  Erosion 3.  .  Maintenance  Road m a i n t e n a n c e  Slash  e  182  Planning Cutting  8  219  .  .  .  .  .  .  .  .  .  .  .  .  . .  . .  . .  .  .  .  .  .  •  221  .  221  xii  Chapter  4.  Page Timing o f water y i e l d  222  Snowpack management  225  Transpiration reduction  228  Shuswap Diversion to the Okanagan  229  Flooding  231  Fisheries  237  A e r i a l Spraying of Forests  238  Pesticides  238  Silvicides  241  Discussion  VI.  •  .'  241  Logging Operations  242  Log D r i v i n g  246  THE MODEL APPROACH TO FOREST HYDROLOGY  250  1.  Introduction  250  2.  Models For Watershed Management  3.  . . . . . . . . . . •  251  Review of Watershed Models  253  A Rational Interception Model . . . . .  254  Objective  254  Beginning assumptions  255  Constructing the model  256  Adjusting f o r beginning assumptions  260  Further Research Needs  265  xiii Chapter VIIo  Page  WATERSHED STUDIES IN BRITISH COLUMBIA . . . . . . . . . . . . . l o  Research Watersheds  o  o  o  o  o  o  .  o  .  o  o  Objectives of Research Watersheds Representative Watersheds Experimental Watersheds Homogeneity  o  Geology  .  o  .  o  .  o  o  .  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  26?  o  o  268  .  000000  .  o  o  .  o  o  o  o  .  .  .  .  .  .  .  .  n  o  o  .  .  .  .  269 270  .  .  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  .  o  o  27^  o  o  o  275  .  275  o  o  o  o  o  o  o  o  o  o  .  .  o  o  o  o  o  o  o  o  o  o  o  o  Topography  0000000.0000000000000  276  Drainage  o  ^77  o  Meteorology Power  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  O  O  O  Study Area  o  Location  o  .  o  o  o  o  o  o  o  .  o  o  o  .  o  .  o  .  o  o  O  O  O  O  O  O  O  O  O  O  .  O  o  o  o  o  o  o  o  o  o  277  .  o  278  . . o . . . .  O  O  O  .  O  O  O  .  280 280  .000.0000000.00  282  0000.00000000000000000  282  000.0.00000000000000  286  Physiography Climate  o  o  Description of the Region  o  277  Okanagan Valley - Terrace and Esperon Creeks ObjeCtiVeS  o  00000000000000000000  Experimental watershed selection 2.  o  271  o  .  .  o  .0.00000000000000000  Vegetation  Soil  .  o  26?  o  .  o  o  o  o  o  o  o  o  .  287  o  .  o  o  .  289  o  o  .  o  .  289  o  o  o  o  o  o  o  o  o  o  o  o  o  o  .  o  .  o  o  .  o  o  o  o  o  o  o  o  o  o  o  .  o  o  o  .  o  o  o  o  o  o  Geology and soils  o  o  o  .00.0000000000000  289  Chapter Forest The Stlldy  tjrpe  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  293  o  0000000000000000000000000  294  00000000000030000000  294  000000000000000000000  295  00000000000000  J06  0000000000000000  311  Instrumentation Water balance  Are a-elevation relationship Stage-discharge curves Hydro graphs  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  Geology  o  o  000000000000000000  316  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  00000000000000000 o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  318 3**-8 319 319  319  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  3^2  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  323  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  323  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  325  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  325  Calibrating the Watershed  00000000000000000  327  0000000000000000  334  Kamloops Area - Watching Creek o  o  o  o  Forest type  Objectives  3H  o  o  o  The Study Area Location  o  o  000000000000000000000  Physiography Climate  o  o  316  Description of the Region liOCatlOn  o  000000000000  East Kootenays - Windermere and Sinclair Creeks o  o  314  Throughfall i n a forest opening  Objectives  o  00000000000000000  Mass curves of runoff  Meteorological data  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  334  Chapter  '' Description of the Region LrOC&tXOn  o  o  Physiography Gllfliat6  o  o  o  The S tudy Are a LOCatiOn SoiJLs  o  o  5«  o  o  o  o  O  O  O  O  Q  o  o  o  o  o  o  o  o  o  o  o  o  o  o  O  »  a  O  o  o  o  »  o  o  o  o  o  O  o  o  o  o  O  o  o  o  o  O  o  o  o  O  o  o  O  o  o  Q  O  o  o  O  o  o  .  o  o  o  O  o  »  »  o  o  o  o  O  o  o  o  O  O  O  o  o  33^  o  o  335  O  o  o  33^  o  o  O  33^*  O  33^  o  33^  O  O  O  O  O  O  O  O  O  O  O  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  337  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  337  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  o  33^  o  O  o  o  O  o  o  O  Hydrologic Studies on the University of British Columbia Research Forest  6»  o  o  o  Forest type The Stlidy  O  Page  o  o  o  o  o  o  »  o  »  »  o  o  o  o  »  <  >  o  o  o  o  o  t  345  >  Other Watershed Studies i n British Columbia ° « » <. o « » <>  347  Trapping Creek Representative Basin » » » » » . <. » o .  347  Serpentine and Nicomekl Representative Basins . <> o •> <>  348  Okanagan Study Basin = Carrs Landing  8  <  .  o  .  0  o  »  .  <  348  .  Mass Balance of Woolsey, Place and Sentinel Glaciers . g  349  Watershed Management Theses, University of British Columbia  e  o  o  o  o  o  s  o  o  o  o  o  o  o  o  o  a  Vancouver and Victoria Municipal Watersheds 7o  o  o  o  o  o  o  o  <,<.<,  Watershed Research Needs i n British Columbia „ » <> » o o  349  o  <.  350  »  352  xvi Chapter  VIII.  Page  SUMMARY A N D C O N C L U S I O N S  •  357  BIBLIOGRAPHY APPENDIX  I.  362 METEOROLOGICAL OBSERVATIONS  ON TERRACE-ESPEBOH CHEEK  WATERSHED APPENDIX  II.  CALIBRATION  396 O F WINDERMERE  CREEK WITH SINCLAIR  CREEK  .  .  .  404  xvii  LIST  TABLES  OF  Table  1.  Page  Snow  accumulation  New Y o r k 2.  Ratio  (From  of  class  precipitation tation 3.  and and  3  by 9  age  (from  Estimated  . .  C o l u m b i a and  by  mean  inches  and  as  a  p r e c i p i -  percentage  evapotranspiration  119  of  i n  irrigable  (from  B.C.  land  Nat.  in  Res.  British Conf.  Columbia, 1964, 133  class S.M.  of  forest  cover  Simpson L t d . yield  increase  types  on  Tree  Farm  Licence  1962)  207  from logging T . F . L .  No.  9»  by 214  and  water  y i e l d  Experimental annual  (Source:  B.C.  and  Agric. (by  i n  the  Forest,  mean,  Dept.  occurrence  Monthly  33  class  annual  4)  Monthly,  Dept.  in  potential  potentially  water  Simpson L t d . 10.  central  type  Climate  Frost  British  in  121  requirements  Area  conditions  1963.)  Columbia  water  Fraser  9.  of  precipitation  and  and  cover  8.  area  cover  Satterlund  .  Irrigated  No.  7.  to  total  precipitation,  Tables  6.  area to  and  Spring-summer p r e c i p i t a t i o n British  5.  different  classes  annual  4.  under Eschner  and  of  in  extreme  Agric.  the  Okanagan,  B.C.,  and  at  the  Colorado  224  temperatures  in  ° F .  1963)  290  Okanagan V a l l e y  (Source:  S.M.  1962)  291  annual  precipitation  i n  inches  (Source:  B.C.  I963) . the  291  11.  Computed  12.  Are a-elevation  relations  -  ,p!speron C r e e k  watershed  309  13.  Area-elevation  relations  -  Terrace  watershed  309  14.  Discharge  Sinclair  from  Thornthwaite  and  method)  and o b s e r v e d  Creek  Windermere  Creeks,  runoff  .  .  I96I-I965 . . .  297  329  xviii Table 15. Al.  Page Rainfall and mean temperatures for Pass Lake and Kamloops for May-September averaged for the years V)6Z to 1965 Dally precipitation at Meteorological Stations Nos. 1, 2, and 3 on the Terrace-Esperon Creek Watershed for the period June 23 - September 30, 1966 (Source: recording tippingbucket rain gauge c h a r t s ) . .  337  •  396  A2.  Weekly precipitation for Meteorological Stations Nos. 1, 2, 35 for the open site; and for different distances from the bole of a tree i n the forest site, for the period June 17-0ctober 13» I966, on the Terrace-Esperon Creek watershed . . . . . . . . . 399  A3.  Snow survey measurements for Okanagan Valley snow courses for 1966 and averaged for the length of record  400  Evaporation from Ogopogo evaporimeters from June 10 to October 28, I966, at Meteorological Station No. 1, Terrace-Esperon Creek watershed  401  Evaporation from Ogopogo evaporimeters from June 10 to October 28, I966, at Meteorological Station No. 2, Terrace-Esperon Creek watershed  , 402  Evaporation from Ogopogo evaporimeters from June 10 to October 28, 1966, at Meteorological Station No. 3» Terrace-Esperon Creek watershed . . . . . . .  403  Sum of squares and products for annual discharge i n area-inches from Windermere Creek (Y) and Sinclair Creek (X), I96I-I965 . .  404  A8.  Partial analysis of covariance for period of calibration of Windermere Creek (Y) with Sinclair Creek (X) . . . . . . . . .  405  A9.  Monthly water balance calculated by Thornthwaite's method using climatic data for McCulloch, &C. (elevation /,,100 f t . ) , and observed runoff from Terrace Creek for the water year October 1965 - September 1966  A4.  A5.  A6.  A?.  406  LIST  OF  FIGURES  Figure  1.  2.  Page  Hydrographs  f o r Mission,  cipitation  f o r McCulloch,  Hydrograph  f o r Terrace  Terrace  and Esperon  Creeks  and p r e -  B o C , M a y - A u g u s t , I965  Creek,  O c t o b e r 1,  1965-September  302  30,  1966 3.  4.  Hydrograph  f o r Esperon  Hydrograph  o f Lambly  years 5.  303  1924,  Hydrographs Mission  6.  March  1925  Creek  o f mean  mean  October  above  1965-September  1,  Stevens  diversion  discharge  precipitation,  at  March-September  McCulloch,  actual,  British  7.  Area-elevation  curves  f o r Esperon  and Terrace  80  Stage-discharge  curve  f o r Esperon  Creek,  staff-gauge 10.  measurements  Mass  curve  of  1965 11.  at  spruce, 12.  13o  i n  of  stage  .  f o r Terrace of  .  potential based  Creek  1965»  .  .  .  .  on  1965*  Creek,  watersheds  f o r use .  .  .  .  .  .  Creeks,  .  .  .  .  .  .  .  312  .  .  313  with .  .  .  June-August,  315 distances  curves  f t .  i n  an Engelmann from  the bole  height,  f o r Windermere  o o o o o o o « o o o o o o of yield  Sinclair  Creek  310  with .  f o r use  stage  f o r Terrace-Esperon  1 8 i n . d b h , 90  Regression from  30?  308  an opening i n  different  Area-elevation  Sh@dS  runoff  f o r  .  Throughfall stand  curve  measurements  and  Columbia,  equations  Stage-discharge  water  . o o o . s o o o . o . o e . o . .  Creeks  Thomthwaite's  9.  f o r  305  monthly  monthly  evapotranspiratlon  staff-gauge  30,  a n d 1927  and Whiteman  of  Creek,  from  .  o f  a n d 25  an  f i r  Engelmann  f t .  crown  and S i n c l a i r  width  Creek  .  .  water-  o o o o o o e o o « e o o o o  Windermere  watershed  spruee-subalpine  .  Creek .  .  .  .  watershed .  .  .  .  .  on .  317  3*"^  yield .  .  .  .  .  331  XX  Figure  Page  14.  Accumulated June-August runoff from Watching Creek for periods I95O-I953 and 1962-1965 . . . . . . . . . . . . . . . . . . . . .  340  15.  Mass curve of runoff from Watching Creek over precipitation at Kamloops, 1950-1953 and I962-I965 .  341  Maximum and minimum June flows from Watching Creek, 195°-1953 and I962-I965, with means for each period .  3^3  16. 17.  Mean and minimum June-August flows from Watching Creek, 19501953 and I962-I965, with means for each period .  .  3**4  xxi LIST OF MAPS Map  Page  1.  Mean annual precipitation i n British Columbia  2.  Mean annual potential evapotranspiration after Thornthwaite . . .  3.  Mean annual moisture deficit after Thornthwaite . . . . . . . . .  12?  4.  British Columbia's major river basins  128  5.  Mean annual actual evapotranspiration after Thornthwaite  6.  Terrace-Esperon Creek watershed  « . . . 118  . . . . . . . . . ....  125  130 292  1  CHAPTER I. INTRODUCTION The report of the f i r s t Royal Commission on the forest resources of British Columbia stated that the future of the province depended on water, and recognized the relationship between water yields and forested mountain slopes (Fulton et a l o 1910)a  Recent statements by proponents of water-  diversion schemes imply that the economy of not only British Columbia but much of Canada and the United States depends on water from this provinces Because of i t s importance, the water resources of British Columbia must be managed properly, and to properly manage the resource there must be information available as to the amount of the resource, i t s distribution in space and time and how these factors may be influencedo s  The influence of the forest on such factors of the hydrologic cycle as precipitation and runoff has long been debated but only i n the past 9  25 years has much research been carried outc  Research has shown that  forest management has considerable effect on the yields regimej and quali t y of water  0  This research i s reviewed i n this thesis and related to  watershed management i n the various regions of British Columbiac As a resource water i s peculiar i n that i t flows across p o l i t i c a l 9  boundaries9 and the use to which i t i s put i n one area affects i t s usefulness i n other areas»  The British North America act of I867 set forth the  division of governmental powers between the Dominion and provincial governmentso  Some of the problems of water management i n Canada stem  from this divisiorio  The legislative responsibility of managing the water  resource, i t s implications, and the evolution of water policy i n Canada  2 and  British  Columbia  British as  inflow  British  to  river with  obtain  the  other  Columbia,  compared  so  development publicized  as  supply  that of  the  implications  as  well  in  the  of  of  have  the  away  very  the  their  source  States,  form  of  and  outside  being  the  only  precipitation  transpiration,  and  suggested  as  temporal  and  are  runoff,  distribution  has  attracting  serious  to  transfer  of  with  the  i s  industry  to  Some  regard  evolution  water  view  implications  sector.  examined  relation  would  A widely-held  i n  industrial are  that  Mexico.  important  transfer  i n  spatial  have  precipitation  Cplumbia. been  schemes  in  as  United  evaporation,  i s  as  r i s i n g  rivers  outputs  province's  diversion  the  province  Inputs  far  water  of  the  category.  British  diversions  water  province,  in  to  Few  0  understanding  Columbia  abundant  water  herein.  reaches  Columbia,  this  resource  Water British  i n  water  regions  the  the  some  water  discussed  Columbia's  from  important  are  of to  of  with the  water  that  an  this  regard more  their  from  to  widely-  economic policy  i n  Canada. Until Columbia.  1965»  In  that  providing  impetus  Columbia,  many  and with  the  l i t t l e year for  watershed  the  International  increased  investigations  University  particular  of  to  a  of  Forestry,  University  effects  of  intensive  forest  Valley.  of  begun  Columbia.  Faculty  Okanagan  study  were  British  attention  research  research of  been  Hydrologic water by  are  watershed  Decade  and  was In  established  yield  to  in  British  instituted, British  provincial  discussed  Columbia,  on water  conducted  resources..  federal  These  British  management  had  in  this  by  determine  and  timing  agencies thesis  the the in  the  3 Watershed research, especially i n the United States, has provided much information on the influence of forest management on water but i t s transposition to other regions, e.g., British Columbia, i s not always valid because of variation i n climate, vegetation, and soils.  Research must be  expanded i n British Columbia to provide information on the relation of forest management to water i n the different regions of this province.  Needs  and type of research that may best satisfy these needs are discussed hereino While there i s a lack of knowledge of the influence of forest management on water i n British Columbia, use should be made of knox-dedge that has been gained elsewhere that i s applicable to this province.  An example of  this use i s the section i n this thesis on erosion control during logging and road building. Mathematical models are becoming more widely used i n forestry to predict the effect of management practices.  A case can be made for the use of  such models., developed with existing knowledge, to predict the effect of forest management on water  yieldo  The models can be refined as more know-  ledge becomes ayailablec, An example of this i s the rainfall interception model, given i n this thesis, that has been developed by the author using interception data mainly from the western United Stateso  ij. CHAPTER II o FORESTS AND THE HYDROLOGICAL CYCLE To set the stage for discussion of the relation of forest management i n British Columbia to the resource  9  water i t i s necessary to 9  consider the influence of the forest on the individual components of the hydrological eycle water  s  0  The hydrologic cycle denotes the movement of  either as liquid or vapour, from the atmosphere to the earth and  back; to the atmosphere, this cycle repeating continually.. This chapter^ i n reviewing the literature pertaining to the influence of the forest on the hydrologic cycle indicates those fac8  tors of the forest which do have an influences, the degree of this i n f l u ence and the scope of the research that has been carried out i n this 8  fieldo  Some of the investigations reported here are not necessarily  directly applicable to British Columbia i n that the species and other eonditionsc, such as climate province,  s  are different from those met i n this  Howevar some knowledge of these investigations i s nes9  essary to appreciate the forests" influence on the water resource^ to isolate water problems i n British Columbiag, and to consider ways of alleviating those problems i n which the forest plays a parte  lo  RAIN  Annual Rainfall The component of the hydrologic cycle that i s most obviously the immediate source of water for use at or near the surface of the earth i s precipitation..  The effect of forest on precipitation has been debated  5 for many years by observers who cited various kinds of evidence to support their views»  Such views ranged from belief i n a decrease i n the  sum total of precipitation f a l l i n g on the globe as forest areas have been denuded.,, to the opposite belief (Belgrand 1854 cited by Marsh f  1965)"  Between the extremes views were held such as were expressed by a  Marsh (1965s V  158)5  "We may well admit that i t (forest removal) has  lessened the quantity jof precipitation] which annually f a l l s within particular limits," The poet Frederick Paludan-Muller  (I896,  p  0  11022),,  i n writing?  Afric's barren sand Where nought can grow because i t raineth notj And where no rain can f a l l to bless the land Because nought grows there s  s  ?  0  expressed the view held by Clave (1862) Herschel (1875) Pavari 8  Blanqui cited by Marsh  (1962),,  1965)0  and Zon  Blanqui (1843)» Coultas (1860)  s  (192?)  9  (GLave Coultas^ s  A similar view i s that a wet region fur-  nishes abundant evaporatien for the production of more rain (Humphreys 193? cited by Penman  1963)0  McKay  (I965)  stated that showers often  follow rainy days because of the evaporation from the wet terrain yet 9  he did n©t hold the views expressed by Humphreys. Warren (19^5)s using data on precipitation near the Sal ton Sea i n California before and after the forming of the lake  9  concluded that  the body of water (440 square miles i n area) had not affected precipitation..  Bernard s (19^-5) data on precipitation and evaporation i n the 8  Belgian Congo indicated no forest influence on the amount of precipitation..  Penman (I963) agreed with Bernard's conclusion though not with 8  9  6 his method of arriving at i t .  Molchanov (i960) also argued against the  view that the presence of forests increases precipitation. The evidence which apparently supports the theory of the forest increasing precipitation i s largely circumstantials according to Penman  (1963) who based his opinion on meteorological considerations only.. 9  He stated that the addition of moisture to the atmosphere, by evapor~ ation or transpirations, i s not a necessary or sufficient condition for an increase i n precipitation near the surface from which the moisture has come* Recently, however, i t has been suggested that sublimated tree terpenes may act as condensation nuclei for water vapour i n the atmosphere.. Hickman  (1966) wondered about the possible effect of this on precipitation  The view was also held that the forest influenced not only the amount of precipitation.but other aspects of the weather as wello Caimi (I857) attributed the increased frequency of hail storms on the f e r t i l e plains of Lombardy to the cutting of forests i n the Alps and Appennlneso  Young (i860) reported that after the forests between the  Riviera and Montferrat had been cut, greater destruction was wrought by hail i n the region of northwestern Italy.. Marsh (I965) wrote that the forest affected local climate, espec i a l l y temperatureo i n the open.  His evidence was the greater depth of frost i n soils  Some writers held that the cutting of forests had altered  the mean atmospheric temperature of large parts of the globe  0  Webster  (1843) wrote that the weather i n the United States was more inconstant after the cutting of large tracts of woodland and that the warm weather  a  7  of  autumn  summer.  extended Abjornsen  tricts  of  Sweden  Effect  of  Wind  Before throughfall, Much  of  effect  the on  and  winter  after  the  forests  the  of  the  its  cold  the  lateness  had  been  influence  evaporation,  influence  and  of  effect  forest  weather of  spring i n  cleared  the  into  many  d i s -  off.  forest  on wind  further  on  interception,  should  be is  considered..  on  these  variables  due  to  its  by  some,  for  example,  Dussard  the  Cevennes  i n  whose  c h i l l i n g  blasts  wind.  blamed  views  have  been  held  the  destruction  of  mistral«  northwest  France  for  the  spring  are  often  coast.  into  (1855) r e p o r t e d  discussing  Extreme who  further  However,  fatal this  or to  the  tender  section  forests  of  wind,  vegetation  w i l l  deal  along  with  the  (1842)  south-central i n  Mediterranean  evidence  that  is  less  circurnstantialo As  wind  moves  by  the  surface,  of  the  surface.  40  per  cent  i n  the  forest  height  at  the  i n  The that  open i s  the  using  the  wind in  reduced open of  15  m.p.h.  surface,  the  wind  open  velocity  from for  the 15  speed i n  the  above i s  and  forest  is  the  height  the 70  The of  the  the  canopy when  exerted  roughness  only  20  to  velocity  trees, with  Forest,  above  is  wind  increasing  forest  feet  to  usually  1948).  Experimental  above for  resistance  proportional  attained  Shasta  feet  5 m.p.h.,  frictional  (Kittredge  increases  open  data  a  velocity  the  gradually  speed i s  speed  decreasing  which  Kittredge, wind  of  across  the  wind  showed for wind  a  speedo that  wind speed  i n  8  (I960) d e s c r i b e d  Molohanov forest  on wind  openings of  that  speed i n  2,200  exceeding in  open  in  area,  along with  the  cause  variations  in  tions  also  affect  precipitation  of  Swiss  tation  may  i n  mixed  stand  that  per  of  cent  diameter) (where open;  i n  ent  the  Hursh  (1948)  of  than  3H  i n  into  different  the  the  wind  the  effect  widths.  100  reach  i n  of  i t  reported  of  a  open.  open  seven  (Pinus  ;  f e l l  i n by was  rainfall  this  two  large  nearby  rainfall  passed  i n  to  the  into per  the  cent  adjaoent  sp.)  the  and,  of  Only per  forest  the i n  cent  per  two  calmer  per air,  o p e n i n g may greater  wind  clearings  of  be  amount  20  (Fagus  p r e c i p i -  the  of  than  precipitation  of i n  (8?  feet  in  1.47H in  than  downward  part  He  rain (39  greater  size  sp.).  least  greater  years  (1965)  clearings  cent but  the  different  clearings i n  varia-  the  Geiger  that  cent  forested  summarizing  beech  showed  a  components  Such  country.  and  to  therefore,  (1951)»  crowns;  five was  points.  smallest  tree  wind  clearings  summer r e c o r d s  open)  3»36H  Burger  i n  and  and h o r i z o n t a l  evaporation  that  interception  height)  the  across,  proximate  point.  than  months  of  as  any  at  precipitation  attributed  wind  of  did  above,  80-foot p i n e  i n  clearings  Geiger  of  of  four  tree  open.  width  and  reported  more  of  that  speed  interception  because  H i s  i n  precipitation  be  measurements  reported  openings  changing vertical  reaching  took a  wind  observation,  catch  feet  investigation  conditions.  Variations  of  adjacent  an  the in  the  compon-  the  reason.  a  clearing  9  Evaporation of Falling Rain Pavari (19°2) reported that air temperatures above a pine forest i n Italy were constantly cooler (up to 4°G.) than in the open, up to 1,600 feet, and cooler i n the morning up to 3>300 feet. I f this condition exists during storms, precipitation may be greater on forest areas due to reduced evaporation of the f a l l i n g rain i n the cooler a i r . I f rainfall i s greater over a forest i t has not been proven to the satisfaction of a l l observers, as indicated i n the section on precipitation. The problems involved i n measuring evaporation over forest and non-forest are obvious, and the absence of data on this phenomenon indicates i t s d i f f i c u l t y of measurement or the view that the differences are i n s i g n i f i cant. Interception Rain that has been caught and temporarily held by vegetation: ^a.) returns to the atmosphere by evaporation from the foliage, termed interception loss; (b) i s absorbed by the foliage; (c) drips off the foliage to the ground, termed throughfall; and (d) runs down branches and reaches the ground via the stem, termed stemflow. In many investigations of the hydrologic role of the forest, interception of precipitation has been calculated by the formula.: 1 = Po - Pc  where I Po Pc  = interception = precipitation i n the open = precipitation under the canopy  This assumes that Po i s equal to the catch that would be received above the canopy.  Some investigations cast doubt on this.  An Australian report  (Anon. 19^9) indicated that the average annual rainfall measured above  10 the canopy was only 77 per cent of that measured nearby i n the open  D  Law  (1958) recorded a 13 per cent lower average rainfall catch with tree-top gauges than i n the open at ground level.  Presumably this difference i s  due to turbulence created by the tree tops. Within a stand there are wide variations i n the amount of precipitation intercepted by the canopyo  Interception by single trees i s  usually greatest near the bole, decreasing with distance from the bole. In gaps between the trees i t varies with the size of the gap.  In large  gaps interception may be negative, i . e . , the precipitation reaching the ground may be greater than i n open areas (Burger 1951» Geiger 19&5, Hursh 1948). In a mature stand of Jeffrey pine (Pinus jeffreyi Grev. and Balf.) i n southern California, the percentage interception varied from 100 per cent of total precipitation at the base of a tree to 81 per cent under the edge of the crown for rains of 0.01 inches; from 94 per cent to 48 per cent for rains of 0.06 to 0.10 inches; from 74 per cent to 5 per cent for rains of 0.11 to 0.30 inches; and from 53 per cent to 4 per cent for rains of 0.31 to 1.00 inches (Kittredge 1948). In a dense stand of 40-year old white and red pine (Pinus strobus L. and Pinus resinosa Ait.) i n Ontario for the period May to October, interception was 57 per cent at one foot from the bole, 27 per cent under average crowns, and 16 per cent i n small openings (Beall  1934).  Neiderhof  and Wilm (1943) incorporated the distance from any point i n an opening to the edge of the nearest crown i n mature lodgepole pine (Pinus contorta Dougl.) i n the equation:  11 I = 0.234P - 0.102r + 0.423  where I = interception i n inches P = precipitation i n inches r = distance from any point i n an opening to the edge of the nearest crown, i n feet. A numerical example of the above equation will illustrate i t s use.  When  seasonal r a i n f a l l , P, i s six inches, interception, I, i s zero where the distance from the point i n the opening to the edge of the crown, r, i s 18 feet.  When r i s zero, i„e., at the edge of the crown, I i s 1»82 inches,  or 30 per cent of the seasonal r a i n f a l l of six inches. The obvious method of determining average interception, and the standard method i n use today, i s to average a number of rain gauge catches under the canopy.  However, the wide range of interception often  requires a large number of gauges to arrive at a reliable average, even for a limited area.  0  alternate method.  Recognizing this, Kittredge (1948) suggested an The method he proposed i s to gauge interception at  different positions with respect to boles, crowns, and openings, and weight  these figures by the proportion of the total area occupied by the  different parts of the crown and the openings,,  A sampling scheme using  aerial photos might be used to determine the area weighting factors = I f adjustment were deemed necessary for speed and direction of wind i t could be accomplished by recording interception at the predetermined positions during storms having winds of various speeds and directions.  However?,  by recording interception for a given period, varying wind speeds and directions would probably be sampled i n proportion to their average occurrence and give a value sufficiently precise  0  12  (1919)  Horton by  individual  trees  X  derived and  equations  stands.  For  to  an  estimate  the  individual  total  trees  S *f* K £ T o o o o o o o o o o o o o o o o o o e o e o o where  I  =  total  S  = depth  i n  interception of  intercepted  = ratio  K  of  storage  evaporating leaf  projected  expressed  J  as  a  of  = evaporation  rate  = duration  storm i n  per  of  crown  the  crown  inches  per  hour  hours.  i t  (2)  stands  s  J  i T  i s  i  = intensity  seen  that  per  cent  increase.  equation  becomes.  (1)  given  stand  precipitation  KET«  may  be  i n  rain  i n  inches  interception  per  hour.  decreases  as  PS Ps  = inches  of  divided any  of  and d u r a t i o n  where  the  the  area  cent,  I = s + PKETI of  to  on  100  intensity  For  i n  surface  the  (l)  # - fS f KET~| ........... . . . ..... (2  equation  For  the  T  where  r a i n f a l l  of  E  L  From  area  inches  ' projected  J  or,  interception  the  any  the  over  number o f  the  showers  watershed for  the  months when t h e t r e e s were i n leaf. i n t e r c e p t i o n s t o r a g e , S, and the p r o p o r t i o n  shower  considered  precipitation  by  evaporated  constant.  before  Without  i t  reaches  correction  for  the  grounds  stemflow  Ps  relation  found  i s  that  a  S  linear  varied  function  from  0.01  of  the  to  0.05  precipitation per  and  KET Ps  variety  of  stands  and  species.  f r o m 0.01  shower.  to  0.23  Horton  for  a  the  13  For two stands of ponderosa pine (Pinus ponderosa Laws ) i n 0  Colorado, Johnson's (1942) data gave I = 0.04+  0o06Ps  and I = 0.02+ O.llPs Rowe (1941) reported a linear trend for the winter months for the partly evergreen brush type of Ceanothus. oak (Quercus sp.) and buckeye (Aesoulus sp.), at North Fork, California. I = 0.02  +0.23PS  Neiderhof and Wilm (1943), working in lodgepole pine i n Colorado found evidence that interception decreases with decreasing stand density and volume. Kittredge (1948) graphed the data of Horton (1919) and Mitchell (1930) for elm (Ulmus sp.), basswood ( T i l i a sp.), maple (Acer sp.), oak, pine, hemlock (Tsuga sp.), beech, ash (Fraxinus sp.), and jackpine (Pinus banksiana Lamb.).  Without correction for stemflow,  interception ranged from 40 to 100 per cent of precipitation i n showers of less than 0.1 inch and 10 to 40 per cent i n showers of less than 0.4 inches with intermediate values for the intervening range. p  ELdmann (1959) presented data obtained over a period of five years on 26 European beech (Fagus sylvatica Ehrh.) and 30 Norway spruce (Picea excelsa Link.) stands i n the Sauerland Mountains of West Germany. Ages ranged from 20 to 140 years with about one-half of each group i n the 60 to 100 year range.  Interception per cent decreased as rainfall increased.  For rainfall less than 1 mm. (0.04 in.) spruce intercepted 82 per cent,  14  72  beech  per  intercepted It D.  Don.)  cent  or  l i g h t  of  cent  per  40 of  (1929)  rain  gave  old  a  (Cryptomeria ranged  per  cent  between  species.  difference species  succession  would  species  type  or  rains  in and  be  of  reported  Japan  height  cent  for  132.8  mm.  between  to  increase  more  range  in.).  109)  stands  as  advanced  i n  at  (5«228  for  1963)<>  Penman  less  i n  per  10  values  of  p.  radiata  only  feet,  62  (1948,  stages  a  by  rains  of  different  but  rainfall  interception  expected  spruce  (Pinus  similar  (cited  greater  Kittredge  represented  in*)  pine  intercepted  japoniea). per  (0o80  mm.  Monterey  was  i n  much  f r o m 63 for  i n  (195*0  Tanoka  covering  in.)  The  rain.  rain  data  ( 0.12  different  l i g h t  trees  Interception  Variation  of  20  cent.  that  1949)  seedling  Tokyo.  5  (Anon  than  per  on  sugL  to  greater  a n d b e e c h 18  cent  heavy  heavy  35-y©ar  rainfall  reported  over less  for  per  24  was  and  Hirata  cent;  stands  Meguro, than  3  mm.  wrote:  of  natural a  particular  stage  in  the  succession. To seasonal to  indicate  interception  arrive  at  the  species  -  pine  i n  Ontario  York  -  43  per  series:  -  37  cent; of  Pereira  48  and  of  per  jackpine  21  per  cent  tolerant per  (1952)  bamboo p l a n t a t i o n s  Africa,  suocessional  trend,  from different  interception  interception  and  the  cent had at  compared h i s  1934);  (Beall  hemlock  results  an  1930);  white  -  together pioneer  and  climax  Connecticut  for  them  intolerant  maple-beech i n  data  red  i n  the  New maximum  1910).  years  8,700  (Mitchell  used  and p i e c e d  Wisconsin,  cent  (Moore  six  l o c a l i t i e s  i n  climax  Kittredge  of  feet with  data  i n  the  those  for  interception  Aberdare for  by  Mountains  hardwoods  (oak,  cypress of  East  hickory  15  (Carya cent  sp.)  and p o p l a r  ranged  from  cypress  hardwoods,  58.  for  to  and  8  13,  11,  greater (1.0,  than  44 and  0.79,  as:  gave  a  the  the  and  canopy  floor. mean  on  in.)  i n  the  Australian  interception  ception They  found  mixed  unifying  throughfall forests  of  that  the  i f  29  and  4  with per  (I965) out  i n  Alaska  of  l i t t l e  North of  cent  O.O98  to  i n . ) ,  rainfalls and  20,  per  Carolina  be  mature  America those  of  per  of mm.  23  of  pine  published stands  of  equations  (Patric studies  in  I966). that  rain  have  f a l l i n g  forest  eucalyptus  showed  1944)  United of  predict authors  0  States.  throughfall speculated  mature  author  that  summaries,,  indicated  been  inter-  mature,,  regional  other The  on  the  eastern  to  for  (1951)  and unpublished  stands  reported  (and  interception.  (Millett  other  coniferous  (1944)  cent  Burger's  studies  The  from  per  reached  respectively  noted  50  the  and  per  Stalhfelt  cent  Mauritius  studies.  that  interception  cent).  among i n d i v i d u a l  these  from  per  Monterey  hardwood  might i n  of  of  Sweden  two-thirds  constructed  data  tabulation  North  26,  15 - 22.  s h o w e d 47  reviewed  agreement they  i n  9-18  Switzerland  experience  differed  for  were  values  oak,  spruce  ground,  climax  patterns  western  by  and  forest  the  i n  28;  pine,  mean  upland  and  from  Studies  seasonal  that  of  values  Interception  5^5  (0.0098  mm.  respectively  mean  (1947) s t a t e d  close  hardwoods,  similar  i n  carried  very  stemflow  gave  and P a t r i c  studies  The  bamboo,  55?  2.5  to  Carolina.  respectively.  the  spruce  North  sp.),  species  i n . ) .  interception on  in  0.25  of  three  28 - 37;  Wieke  Helvey  and  0.9  l i t t e r  measurements Vaughan  (1.7  for  and  the  mm.  spruce,  value  moss  for  sp.))  (Cupressus  rainfalls  (1940)  Luchshev cent  (Populus  that rain  suggested  carried  out  in  16  similar  forest  population, In  40.8  i n .  rainfall was  basal  area  of  ception. greater both  i n  4  for  spruce  and  3 mm.  their  for  beech.  per a  Carr.)  ception  of  per  western  reported  that  the  than  i n  period  percentages Luchshev  Lawson  per  3  after  i n  (Pinus  echinata  per  cent the  cent  M i l l . )  winter  cypress  i n in  months  the  f e l l  same  a n d 16.1  of  2 3 , I965. less,  and  during  per  cent  interception  November-April and  31  20  for  rainfall  Ley ton  and  was  Carlisle  (Chamaecyparis the  different  interwas  period  spruce,  for and  (1939) r e p o r t e d  Petrovski  from  varia-  throughfall.  influences  the  the  5 Dim.  lawsoniana peak  in  that in.)  (0.2  (1959)»  11  from  (A.  Murr ) 0  July-August  November.  the  winter  cent  out  summer  Wisconsin,  intercepted  per  on  carried  forest  needed.  or  effect  saccharum Marsh.)  during leaves  i n  i n .  single  also  interception  northern  Carolina  6.6  rains.  cent  (Acer  of  72.5  a  year  being and  not  December  consistent  of  autumn  maple  per  24.6  and  during  to  0.05  time  Russia,  for  of  Investigations  decreasing  forest  North  no  to  from  are  was  13  that  the  for  a  sugar  summer  cent  in.)  cent  cent  had  storms  maximum i n t e r c e p t i o n  (0.1  In  15.8  the  In  measurements  throughfall  during  indicate  random samples  from July  season.  beech,  reported  17-18  f e l l  May-October  and  study,  acre  (1959)  measurements  Pari.),  (L.)  the  spruce  per  year  Eidmann  and  of  the  that  with  as  throughfall  negligible  Variation seasons  regarded  (1966)  Patric's of  i n  are  additional  Throughfall tions  types  -hemlock  i n 17  the per  cent  (Kittredge l o c a l i t y during  trees  f a l l . of  were  i n  and  mixed hardwood  the  precipitation Old  shortleaf  interception  summer.  leaf  inter-  Old  1948). had  canadensis  (1930) r e c o r d e d  Mitchell  s p r i n g when  (Tsuga  of  15.7  i n i n  pine per  17  For most evergreen species a. large proportion of the annual leaf f a l l i s concentrated i n the autumn and the new foliage develops i n the spring.  There i s less foliage i n winter, the difference being reflected  i n interception.  Another reason for the decreased interception loss of  conifers in winter might be that because of lower air temperature and higher humidity less water i s evaporated.  Interception loss, which by  definition (p. 9 ) i s precipitation that has been intercepted by and evaporated from foliage, i s therefore less and throughfall greater. An example of this was given by Pearson (1913) for ponderosa pine at 7,250 feet elevation i n Arizona.  Interception was 40 per cent, a  higher value than would be expected from this species i n that region where i t grows i n open stands and has foliage of low density. In other investigations the interception was, for mature stands of ponderosa pine i n Idaho, 22 per cent and 2? per cent (Connaughton 1935)» and for young stands i n Colorado, 18 per cent (Johnson 1942).  The reason suggested by  Kittredge (1948) for the surprisingly high figure of 40 per cent i s the high "evaporative power" of that region. Variation with stand density and, age.  Delfs et a l . (1958) com-  pared interception and stem-flow i n pure spruce stands of different ages in the Oberharz Mountains during 1952-1955*  Measurements were made on  "normal" crown cover, those on the plantation being shortly after crown closure.  The results showed that interception i s greatest i n sawtimber,  averaging 36 per cent, followed by poles, 28 per cent, saplings, 21 per cent, and i n the. young plantation, 0.6 per cent.  18  In balsamea  Maine,  interception  (L.) Mill.)  o f light-foliaged  spruce  and  stand  o f Douglas  white  a value  a crown  density  f a l l ,  while  a 25-year  o l dstand (19^)  cent  decreases  as indices  area  p e racre,  decrease.  Variations following  figures Age  with  annual  that  current  although  correspond, of  current  was  reported such  Franco)  that  —  b yt h e  1927):  20  50  60  90  2  27  23  27  p e r cent increment  occurred  a t 50 y e a r s  culminated.  which  i n turn  relative juniper  a function  to precipitation (Juniperus  deppeana  1964).  throughfall  i s  from  Steud.)  Interception gross  i s  by t h e useo f t h e canopy  to the curve  (Torr.)  was c a l c u l a t e d  camera.  o f  foliage.  d e n s i t y was  on t h e Beaver  precipitation,  suggested  do n o t exactly  similar  a n dcrown  was t h e a g e  (1948)  o f t h e amount  osteosperma types  which  Kittredge  stands  determined  and basal  be i l l u s t r a t e d  i n well-stocked  (Skau  43 p e r c e n t  intercep-  i n p e r cent  (J.  Washington,  o f the rain-  as number o f t r e e s  (Zon  with the  the interception p e r  interception  juniper  i n  intercepted  a n di n c r e m e n t  growth  and  also  com-  A mature  34 p e r c e n t  canopy  a  Marsh.)  1948).  o f interception  shed i n Arizona stemflow  dense  (Abies  containing  the trends  i n t h e Utah  alligator  (Mirb.)  intercepted  o f density,  f i r  papyrifera  (Kittredge  menziesii  —  annual  Interception studied  stands  t h e a g e o f t h e s t a n d may  maximum i n t e r c e p t i o n which  p e r cent  f o r beech i n Switzerland  tion  at  whereas  with  i n years  Mean  The  26  andbalsam  (Betula  o f 65 p e r c e n t ,  Kittredge  1931).  o f  birch  f i r (Pseudotsuga  with  (Simson  spruce  w a s 37 p e r c e n t ,  ponent  f i r had  under  L i t t l e ) and Creek  by deducting  a n dcanopy  Stemflow,  water-  density  w h i c h was  19 only one to two per cent of total precipitations began after the comparatively large value of 0,20 to 0,30 in<> of precipitation had falleno Throughfall was predicted with reasonable accuracy for either species by the equation I s 0,044 + 0,865 (gross precipitation i n inches) ~ 0,216 (canopy density index as a decimal fraction of 1,000), Stemflow,  Stemflow has been found to increase with the amount of  precipitation per shower and, for some species and stands at least, the relation i s linear (Kittredge 1948),  Stemflow begins only after a  certain amount of rain has fallen, the amount differing for different species, Stemflow may start at an amount of rain as low as 0,01 i n , for smooth^barked trees (Kittredge 1948),  9  or as high as 0,7 i n , for rough-barked trees  Wilm and Niederhof (1941) computed regression equa-  tions for three species at 9 9 500 f t , elevation i n Colorado,  For lodge-  pole pine, Sfv a 3583Pr - 1090  For alpine f i r (Abies lasioearpa (Hook,) Nutt,)  s  Sfv = l603Pr - 387 For Engelmann spruce (Pioea engelmannii Parry)  9  Sfv = 1053Pr - 301  where Sfv = stemflow i n cubic inches Pr  = precipitation per shower i n inches  In this investigation i t was found that stemflow started only after 0,3 i n , of rain had fallen. In a 25-year old plantation of Canary pine (Pinus canarienses C, Smith) at Berkeley, California, the equation for the stand was  Sfd = 0„03Pr -  0.02  where Sfd = inches depth on the area of the projected crown For individual trees i n this stand the Y intercept varied from -0.002 to -0.036, and the regression coefficient from 0.005 to 0.11.  No relation  was found for this variation but a relation was shown with the excess or d e f i c i t of height relative to that of surrounding trees.  The relatively-  t a l l and relatively short trees showed high stemflow, 2.5 to 9 per cent of precipitation compared to one per cent for those of average heighto A nearly linear relation between annual volume of stemflow and basal area of individual trees was found by Wicht (1941) for gray poplar (Populus x canescens (Ait.) Sm.) i n South Africa.  The author reported  that the ratio of stemflow from sample trees to stemflow from a l l trees on an acre equalled the ratio of basal area of the sample tree to total basal area on the acre. Hoppe's (I896) data also indicated that for European beech the volume of stemflow increased linearly with the stem basal areas and crown areas of the trees (reported by Kittredge 1948). On the other hand, the stemflow as a per cent of precipitation decreased with increasing crown area, from 19 per cent at less than 108 sq. f t . of crown area to 15°5 per cent at 150 sq. f t . Twenty-five year old shortleaf pine stands i n North Carolina yielded one to five per cent of precipitation as stemflow (Munns and Sims 193&; cited by Kittredge 1948).  Mature lodgepole pine i n Colorado yielded  less than 0.1 per cent of precipitation as stemflow. A 32-year old stand  21 of lodgepole pine yielded 1.5  per cent of the total seasonal precipita-  tion whereas a nearby aspen (Populus sp.) stand of the same age yielded only l o l per cent (Dunford and Neiderhof 1944),  This low stemflow value  for the smooth-barked aspen i s contrary to the evidence of high values for smooth-barked trees. An 86-year old beech stand i n Austria had stemflow starting at 0.1 i n . of rain, reaching 21 per cent of precipitation i n rains greater than one inch. The average for rains of a l l intensities was 15.4  per  cent for beech, 2 3 per cent for spruce, and 0.7 per cent for the rough0  barked pine  Q  In rains greater than 0.6 i n . per cent stemflow exceeded  per cent interception for the beech (Hoppe I896; reported by Kittredge 1948)o  Hamilton and Howe (1949) reported that trees with smooth, upright stems carried 25 per cent of the r a i n f a l l to the ground, whereas trees with spreading branches and rough bark carried only about seven per cent.  Kittredge (1948) presented a graph of amount of stemflow over  r a i n f a l l by species. In order of increasing stemflow they are: shagbark hickory (Carya ovata (Mill,) K, Koch), oak, hemlock, basswood, pine, elm  ;)  ash, maple, and beech. Fog drip.  Fog drip can occur where fog impinges on vertical sur-  faces and drips from the foliage.  The effect i s limited to where fog i s  prevalent and i s usually an edge effect only, not reaching far into a forest. Data for the Taurus Mountains i n Turkey indicated that i n a very foggy month the "rain" at the edge of a forest may be three times as  22 great as that i n the open, and over a period of four years i t was one and one-half times as great (Linke 1921, reported by Penman 1963)0  At  Kisantu i n the Belgian Congo, fog drip acoounted for 12 per cent of the annual r a i n f a l l of 63 i n . (Aubreville 1949). Isaac (1946) reported that on a ridge i n Oregon, two miles from the ocean, the rainfall under the trees was one and one-quarter times as great as i n the open. The amount of fog water caught by a stand of Taiwan spruce (Picea glehnii sensu Matsum. and Hay.) i n Japan was six to ten times the amount deposited on the ground in the open (Hori 1953)°  Kashiyaraa  (1956) showed the effect of a model shelter belt of conifers 6.5 f t . high and 43 f t . wide, on the coast of Japan. Intercepted fog reaching the ground under the trees was about 0.04 in./nr. on the windward fringe, or about 100 times the rate i n the f l a t , treeless grassland. The extremes that have been recorded are from one of the bestknown examples, Table Mountain, S. Africa. 21? mm„ (8.54 in.) to 398 mm.  Monthly values ranged from  (15.67 in.) (Nagel 1956).  Oberlander (1956) measured fog drip during a period of 40 summer days without rain i n the San Francisco peninsula, California. 20-ft. tanoak (Lithocarpus densiflorus (Hook, and Am.)  Under a  Rehd.), 59 i n .  of fog drip were recorded, more than the total rainy-season r a i n f a l l i n the surrounding area.  In contrast, Kittredge (195*0 reported that fog  drip rarely reached 0.01 in./day at Berkeley;, California. Grunow (1955) reported that i n Austrian spruce forests interception can be compensated for by fog drip.  Hirata (1929) (cited by Kittredge  1948), i n Japan, indicated that for the months of April and July, 1922,  23  there were apparently p o s i t i v e contributions by fog d r i p , i e , t o t a l 0  0  r a i n recorded under the canopy, taking i n t o consideration the l o s s due to i n t e r c e p t i o n , was greater than i n the open. Rubner  (1932), (reported by Kittredge 1948), studying spruce  forests i n Germany, came to the conclusion that fog d r i p was proportional to the r a t i o of v e r t i c a l crown area to horizontal crown area»  Fog d r i p  under ceanothus (Geanothus leucodermis Greene) increased as the height o f the shrub increased (Kittredge 1948 )„ Water l o s s *  I t has been generally accepted that p r e c i p i t a t i o n  i n t e r c e p t i o n by f o l i a g e causes a l o s s of water from the s i t e *  However,  the r e s u l t s of recent studies seem to i n d i c a t e that there i s l i t t l e , i f any, net l o s s of water from the s i t e because o f a compensating reduction i n t r a n s p i r a t i o n caused by the evaporation o f the intercepted moisture,, Burgy and Pomeroy  (1958) reported that i n a study using grasses  and sunflower plants i n nutrient solutions i n a greenhouse, t r a n s p i r a t i o n was l e s s from wet leaves than from dry leaves*  McMillan and Burgy  (19°0)  c a r r i e d out a s i m i l a r study with grasses i n lysimeters i n which s o i l moisture was maintained by i r r i g a t i o n between f i e l d capacity and 50 per cent of f i e l d capacity*  Results were s i m i l a r to those reported by Burgy  and Pomeroy (1958)o Goodell  (1963) discussed the r e s u l t s of the studies noted above and  made several points concerning the apparent compensation f o r i n t e r c e p t i o n by reduced transpiration* He questioned t i o n i n view of (1)  the magnitude o f the compensa-  the f a c t that plants regulate t r a n s p i r a t i o n when  water a v a i l a b i l i t y i s l i m i t e d , (2)  the p r o b a b i l i t y that more energy i s  24 available for evapotranspiration from wet leaves due to heating of the water film by radiation from the leaf.  On dry leaves this escapes into the  air, and (3) i n cold winter climates, soil moisture availability more than energy may limit transpiration. Interception may then increase the amount of water evaporated by increasing the amount of water to which the excess energy ca.n be applied. In summary, interception varies from a very small percentage of r a i n f a l l for heavy rains to 100 per cent for very light rains. Interception increases with increasing stand volume and density, and varies with species, age, and season.  Stemflow begins after a certain amount of rain has  fallen (as low as 0.01 i n . for smooth-barked trees and as high as 0,7 i n . for rough-barked trees), increases as r a i n f a l l intensity and amount i n crease, and ranges from zero to 25 per cent of r a i n f a l l .  Fog drip as high  as 45 in./month has been recorded and i n localized areas may contribute as much water as does r a i n f a l l . Evaporation from Foliage Most of the water intercepted by foliage, other than stemflow, i s evaporated.  "Most" i s used because of evidence of direct intake of water  by aerial plant tissue. Fine seedlings whose tops were kept i n a moisturesaturated atmosphere with roots sealed i n empty flasks, transferred water from the atmosphere to the flask through the roots (Stone et a l . 1956). Moisture movement was attributed to the vapor-pressure gradient between the saturated atmosphere and the air i n the flasks. demonstrated this phenomenon.  Slatyer (1956) also  The importance of this i n the hydrologic  cycle i s not known, but such atmospheric and soil conditions would not be expected to occur often i n most climates.  25  Moisture Storage i n Vegetation Satterlund (1959) indicated that the change i n moisture content of the vegetation i t s e l f can be an appreciable factor i n the water balance of a watershed.  By calculating the possible changes i n moisture content  of different species throughout the season he concluded that a rough, and probably conservative, estimate of possible vegetation storage ranged from 0 , 0 5 in» for an 80-year old beech stand on a poor site (1,030 cubic feet/ acre) to 0 8 l i n for a Douglas f i r stand, age 1 0 0 , on a good site (19,820 o  0  cubic feet/acre). Condensation Whether condensation of water vapor from the atmosphere, i,e,, dew i s a significant part of the moisture reaching the ground i s doubta  ful.  According to Zon (192?) dew and frost i n northern latitudes amount  to only 0 , 4 to 0 , 8 i n , annually.  In meadows i n England one inch of dew  annually has been reported (Kittredge  1948), Harrold and DreibelMs  (1945) reported that monthly averages for the years 1943 and 1944 ranged from 0,12 i n , i n July to 0 . 8 5 i n , i n January i n lysimeter studies at Coshocton, Ohio,  However, i t was later found that the lysimeter weight  changes were affected by grease seals on the lysimeters.  The authors  stated (Harrold and Dreibelbis 1962) that the previously published values of dew are much too large. At the Femow Experimental Forest i n West Virginia, 0,259 i n , of dew was recorded during the period May - November, 1 9 6 2 , The July September amount was only 1 , 2 per cent of the 1 0 , 7 6 i n , of precipitation  26 that occurred during that period (Hornbeck 1964)<>  Lloyd ( I 9 6 I ) reported  that total dew recorded in northern Idaho for the July - September, 1958» period was Go39 in<> or 13 per cent of the 2 9 6 i n of rainfall during 0  s  0  that time  0  The values given in the previous paragraph are for dewfall in the open« Lloyd ( I 9 6 I ) found no dewfall under a closed forest canopy but heavy dew on top of a closed canopy of aldero  Geiger (1965) stated that  dew falling in the open was greater than in the forest^ the dew being deposited on the upper crown surface in the forests It appears then . 9  5  that the amount of dew, whether on the crown in the forest^ or on the ground in the cpen§, is usually a small percentage of the precipitationo That which is deposited on crowns is lost to evaporations, but transpira= tion losses are probably reduced because of thiso  Probably soil moisture  loss by evaporation is reduced also by evaporation of dew on the groundo Therefore i t appears that the influence of the forest on this variable in the hydrologie cycle is slighto 2o SNOW Interception There is wider variation in snowfall measurement than in rainfall measurement because of the greater affect of wind on the falling snowo Snow interception has usually been estimated by subtracting gauge or snow course measurements taken beneath the canopy from similar measurements taken In forest openings  0  However$> the sum of intercepted snow and  accumulation under the canopy does not necessarily equal snow accumulation  27  i n the open. In storms of low wind speed and wet snow, the annual catch at crown level i s about the same as the catch i n small openings (Rowe and Hendrix 1951)9  D u t  the relation i s not known for single storms especially when snow s  i s dry and wind speed i s high. Another factor clouding the issue of comparisons of snowfall i n forest and i n openings i s the effect of wind turbulence on the accumulation i n the openo  The accumulation i n the open i s used as the base but i s i t s e l f  affected by turbulence, which i n turn i s influenced by such factors as size and orientation of opening, and height and roughness of tree crowns. The effect of roughness of the upper surface of the forest canopy on f a l l i n g snow has received very l i t t l e study as well.  Komarov (1963, cited  by Miller 1964, p. 2) stated that deposition of snow "depends on the difference between at least the cube of the i n i t i a l and final velocities" of the wind, so that a small decrease i n wind speed results i n a large deposition of snow. Where the roughness of the forest canopy i s increased e.go, where there i s a forest opening, greater deposition of snow would be expected. Another aspect of the problem i s the definition of interception as applied to snow. - In a preceding section, interception loss was defined as that moisture which i s caught by the foliage and evaporated. Snow that has been intercepted by tree crowns may remain there for a considerable time (Lull and Rushmore I96I). cause the snow to be deposited on the groundo  A thaw or high winds may Therefore, the moisture  loss involved i s not equal to the i n i t i a l interception, but only to the amount of sublimation and evaporation that has occurred while the snow  9  28 was lodged i n the crowns  0  In the studies reported below interception i s snow intercepted s  by crowns and interception loss means only that part evaporatedo Penman (1963) quoted a study by Rutkovski and Kuznetsoya. (1940) indicating that maximum snow wa.s held under mature broad-leaved stands  9  young stands holding about the same as i n the open, and conifers usually lesso  Interception o f snow at an elevation of 4,500 f t i n southern 0  Idaho amounted to 30 per cent of the total f a l l i n an old stand of ponderosa pine with a partial understory (Connaughton 1935)°  In a sim=  i l a r stand without the understory the value was 25 per cent, and i n an open stand of ponderosa pine and lodgepole pine, 20 to 30 fto high only 9  five per cento Interception loss from a. dense pine stand at the Central Sierra Snow Laboratory i n April, 1958, was eight per cent o f the precipitation (West and Knoerr 1958)<=  Interception during snow storms i n an 80-year  old ponderosa pine stand at Bass Lake, California^ was 10 per cent o f precipitation (Rowe and Hendrix 1951)° i l a r data for other forest types  0  Kittredge (1953) reported sim-  Interception losses during .an average-  size storm of two inches were 11 per cent for mature ponderosa pine  a  15  per cent for mixed conifers, and 16 per cent for dense stands of mature red or white f i r (Abies concolor (Gordo and Glendo) Lindlo and A magnifies. Ao Murr )o 0  0  The effect of forest cutting on interception losses  i s about proportional to the amount of the cuto  Kittredge (1953) reported  for a selectively-cut forest, a 50 P** cent decrease In interception for e  a 50 P©r cent removal of the tree canopy  0  29  Miller (1964), i n analysing data published by Kittredge i n 1953» concluded that selective logging influences interception less by changing crown cover than by removing dominant trees that project above the canopy, and perhaps by making forest edges more porous.  Both conditions act  directly upon snow which, because of the wind, has a large horizontal component to i t s f a l l . Goodell (1959) reported that a dense coniferous forest i n Colorado can, by interception of snow and direct evaporation, allow a loss of up to 30 P©r cent of annual snowfall.  Reductions i n loss due to logging  were estimated by Anderson and GLeason (1959) for a winter i n which precipitation was 38 to 41 i n . ; 3-4 i n . for a strip-cut area, 2.3 i n . for a block-cut area, and 1 6 i n . for a selection-cut area. 0  As an indication of the weight of snow which may accumulate on foliage the results of Seppanen's (1959) investigations are given. In pine stands of medium density at nine snow stations i n Finland the 2 snow lodging on branches averaged 2,600 kg./lOCm. of ground area, or 104 tons/acre, on January 16, 1959«  The range was from 1,400 to 4,500  2 kg./100m.  (56 to 179 tons/acre).  Accumulation The effect of wind on the catch of rain was discussed i n a previous section. The effect of wind on snow accumulation i s much greater because of the greater buoyancy of snow flakes compared to rain dropSc The effect i s more obvious also because the snow does not generate runoff immediately, and the precipitation of many storms often accumulates before  30  melting and running  offo  The following literature survey indicates the forest management practices which may affect snow accumulation, and the size of the i n fluence. In the open. In the lee of a shelterbelt i n South Dakota at the end of February 100 i n , of snow accumulated, whereas to windward, and beyond the influence of the belt to leeward, the depth of snow was less than 20 i n . Maximum drifts were at 3H (H i s the height of the tree or stand) and the effect was noticeable as much as 8H to leeward (Stoeckeler and Dortignac 1941)» F f o l l i o t et a l o (19^5)» working i n the Coconino National Forest, Arizona, measured the water equivalent of snow on the day following each storm  The study areas a l l had north-east aspect with slope less than  0  10 per cent, and the wind direction during the study was south-west. Snow accumulation i n inches of water equivalent was a maximum at IH, while the snow-melt rate was least at the edge of the opening, increasing to approximately 1§H where i t levelled off. Martinelli (19&5) investigated the depths of snow accumulated behind slat-and-wire fences i n alpine areas of central Colorado.  The results  are pertinent i n that they show the effect on snow deposition of air flow barriers and the extent of the effect.  In the investigation, snow  fences of 1.2 and 2,4 m. (3°9 and 7.9 ft.) were used to determine i f such barriers would produce snow fields that would persist until late summer.  The research showed.  (1) a positive effect on snow accumulation  31  usually extended 8H to 12H beyond the fences, occasionally extending to 20H on level terrain, (2) i n steeper areas, especially where wind flowed downslope before striking the fences, this distance decreased to 6H to 8H, (3) the values for level terrain f a l l close to the 10H to 25H reported by Schneider (1959)» (4) the more frequent values of 8H to 10H also agree with that found using the equation attributed to German workers by Pugh (1950, cited by Martinelli 1965), L = 36 + 5H K where L = length of d r i f t i n feet H = height of fence i n feet K = proportionality factor of 0o9 for the type of fence, (5) the maximum depth of snow was at 3H to 5H» (6) maximum depth of snow varied from 0„5H to 0 „ 6 H at one catchment, to 1 2H 0  In the forest.  to 1«5H at another  0  Hoover and Shaw (1962), at the Fraser Experimental  Forest, Colorado, determined that a forest opening i s most effective as a snow trap i f i t i s at least 2H wide, and that openings should not be greater than 10H wide. Many studies show that snow accumulation i s maximum i n openings of approximately IH i n width and the opening should be i n the form of a cut strip of that width (Church 1912,  Kittredge 1953  9  Anderson 195°* and  Anderson, Rice and West 1958)° Anderson and Gleason (1959) gave a graph of snow accumulation i n forest openings which showed that snow depth leeward of the opening was less than to windward, indicating that snow was "stolen" from the leeward forest, i«e., total accumulation i n the open was made at the expense of  32  accumulation sists  longer, In  between  mature  the  one  distance  of  JO  However,  runoff  that  the  inch f t .  from  water i n  beneath  pine  under  the  equivalent ft.  15  i n  The  JO  to  such  drifts  the  snow p a c k  per-  0  70-foot l o d g e p o l e  trees  of  near  Fraser,  crowns of  the  relation  f t .  beyond  out  into  snow was  the  Colorado, the  maintained of  and  openings  increased  edges  Wilm  linearly from  the  at  a  crowns  into  openings. A  study  of  the  accumulation  near  accumulation  was  under  cover  l i t t l e  cover,  per  5°8  (Jaenicke  and  Many f a i l  to  ingfulo  Table  of  snow  and  to  April, site  crements  per  cent  of  during between  a  the  under  relation  and  the  7°4  than  ponderosa pine i n  i n  per  an  an  cent  on  opening i n  extensive greater;  complete  cover  32.5  of  cover  to  forest  " f u l l " .  In  Column  4  is  period,  sampling  a  crown  densities, study  quantitatively  combination  equivalent  the  showed;  greater was  of  snow  the  forest  opening;  under  per  partial  cent  less  1915)<>  described  i s  water  1962o  and  adequately  was  cover  Arizona,  cent  less;  Foerster  1  crown  accumulation  " p a r t i a l " ,  density  of  Flagstaff,  studies  (I963)  effect  I5.6  describe  " l i t t l e " ,  the  f o r e s t«  found  rate  the  the  prolonging  (1940)  Collet  the  in  of  were the and  dates.  two  by and  tables  measured  column  5 i s  the  use  Eschner is  accumulation such  and  their  from  more  the  as  mean-  report.  November,  equivalent sum o f  terms  Satterlund  therefore  from  weekly  maximum w a t e r  but  snow  Depth 1961,  recorded positive  on i n -  33 Table  Snow  1.  in  accumulation  central  under  New Y o r k  different  (From  cover  Aschner  and  conditions Satterlund  1963.)  Basal Cover  area  per  Winter  acre  crown  ft.  per  sq.  Max.  accumula-  tion  on  density  Total  ground  water  water  0  2.25  6.07  31  2.8  5.15  9.23  133  7.6  4.90  7.28  Brushy hardwoods.. Northern hardwoods.. Thinned red  p i n e . . .  109  85  4.90  6.44  pine..,  196  93  4.05  5.33  163  94  3.05  5d3  139  96  3.25  4.80  Dense red  Thinned way  Nor-  spruce.  Dense way  Norspruce.  Dils red  pine  of  of  snow  i n  the  open  of  190  sq.  l o s t  by  eauivalent  0  land.e«o  and  different  to  9  (1956) i n v e s t i g a t e d  Arend  decreased  stand  as  12  the  i n .  ft./acre).  evaporation  Evaporation  from  Because complete,  30-  27  inches  equiva-  lent Open  Nov.  Apr.  inches  cent  accumu-  lation  the  basal  in  a  The  and  densities area  stand snow  in  of  of  accumulation  Michigan.  the  80  the  sq.  intercepted  stand  The  ft./acre, by  snow  under  accumulated  depth  increased  tree  to  of  (from  18 a  i n .  9  i n .  in  stand  crowns  was  reported  sublimation.  Snow the  amount  snow of  pack  persists  moisture  l o s t  for from  some the  time pack  before by  melting  evaporation  is has  as  34 been the subject of numerous invest!gations  0  One method of estimating  such loss i s by periodic weighing of glass jars containing snow= A study at  7 » 0 0 0  elevation i n Utah using glass jars showed a  fto  mean evaporation rate of  0  0 1 7  0  in„/day for November  7  to May 4  0  During  the snow season ( 1 8 0 days) the total evaporation was three inches, or 14 per cent of snowfalio  Evaporation increased at an accelerated rate with  increasing a i r temperature (Baker oration of On May 8  S  Qo04  191?)=  ino/day for May at  8 5,700  Croft  (1944)  f t elevation i n the same areao 0  evaporation from snow cores i n pans was 0  to wind and  0  C  0 2  reported mean evap-  o  0 5  i n where exposed 0  In, where there was no wind movement,, The effect of solar  radiation was small as shown by the difference i n evaporation between sun and shade of only Church  in  0o002  0  reported the following November - March evaporation for  (1934)  a study conducted with pans of snow at tree-crown level at Lake Tahoe, Nevada: open meadow 8 5 in= of water equivalent; semi-open pine forest 9  4 8 i n ; f i r stand 8  0 c 0 5 ?  e  9  0o032  9  0  2 „ 4 in  9  and 0 0 l 6 o  o  9  In inches/day the respective amounts were  0  Houk (19ZL  9  cited by Kittredge  1948)  determined  the rate of evaporation from snow from December 1 9 1 ? 9 to Februarys 1 9 1 8 , 9  i n 0hio to be C- 023 in /day 9  O  0  0  Measurements of evaporation were made for several years under a range of conditions from open meadow to dense forest.on the Stanislaus National Forest i n Galiforniao  Median evaporation for a l l stations and  35  years was 0 007 iru/24 hours o  0  For 1936 the median was 0 013 and i n 1938, o  -0,002 in,/24 hours (the negative value indicating that condensation exceeded evaporation).  For individual forest types the medians ranged from  a maximum of 0,12 in,/day under a mature, open stand of ponderosa pine, to -0,002 in,/day in. dense stands of white f i r , red f i r , and ponderosa pine.  Records taken morning and evening at a limited number of stations  showed that evaporation exceeded condensation i n 83 per cent of the day periods, and condensation exceeded evaporation i n 72 per cent of night periods (Kittredge 1948).  Apparently evaporation from snow on Pacific  slopes of the western mountains i s much less than that i n the interior, the difference presumably being associated with more humid winds from, the Pacific Ocean, In large, exposed openings i n California, evaporation minus condensation totaled 2,1 i n , during the winter of 1957-19585 i n small forest openings gains by condensation essentially balanced losses; and under forest canopies a net gain of 2.3 i n . was measured. Only during a dry spell i n late February to April, 1958, did significant evaporation from snow surfaces occur (Anderson 1958). the Central Sierra Snow Laboratory.  Similar results were obtained at February to June loss i n a small  forest opening was 0,8 i n . while under the canopy the loss was 0,3 i n , (Anderson 1958), Hutchison (I966) compared evaporation from snow and s o i l surfaces i n the central Rocky Mountains, Colorado, during the spring of 1961, Measurements were made i n forest openings at 9,000 feet elevation using  36 evaporation pans set i n the s o i l or snow. Evaporation losses from wet s o i l surfaces were much greater than from adjacent melting snow surfaces, averaging 0 1 7 0 5 i n . for s o i l and O0O36I i n , for snow, from April 21 to May 9° O  This may be 33.plained by increased atmospheric vapour pressure during spring due to increases i n ares, of exposed wet s o i l and available energy. Vapour pressure gradients between both surfaces and the air will then decrease but the gradient between s o i l and air w i l l decrease least because the soil temperature can rise under a given level of energy input and the vapour pressure of the s o i l water w i l l rise correspondingly.  The vapour  pressure of the melting snow surface i s fixed at a value correrponding to 32°F. Bergen and Swanson (1964) studied evaporation from snow at 9*000 f t . elevation i n Colorado using the energy budget method. Measurements were made of snow temperature and density j, s o i l heat flux, incident radiation and the difference between this flux and reflected or emitted radiation from the snow wind speed shear, and a i r temperatures at intervals above s  8  the surface^, and a i r humidity. 0.02 to 0.0? i n  c  Daytime evaporation losses ranged from  and averaged Q 04 i n . for the five measurements made  from February 1 3 to March 23*  o  Nighttime condensation ranged from 0,00059  to 0.012 i n . =, averaging 0.0076 in„ for four measurements. At the Central Sierra Snow Laboratory evapora,tion was greater i n the open than i n the forest during the day, and less i n the open than i n the forest at night (West 1959)°  37  In  0.1  over  ported the  summary, in./day  being  forest,  tion  of  those  solar  data  are  therefore In  of  on  the  i s  a  high  most  higher  density  to  snow m e l t  i n  of  slightly  common r a t e i n  the  the  open  point  air,  (long  latent of  depends  snow m e l t i n g .  terrestrial  conduction  was  for  i n  heat  constructed (Rantz  0.054  from  32°F.  rate  i n  period  i n . is  from  Horton  Recorded  an  water a  and  melt  rethan  where  of  from  the  i t s  Those  wave)  heat  on  i n  condensa-  influence  sources  radiation,  vaporization ground,  and  the  using  are  conby  con-  the  heat  approximations  based  approximate  rates  for  22  -  May  equivalent of  the  (Clyde  one  reference  New Y o r k  9  i n .  degree  state.  on  the  average  1931? per  i n  empirical  i n  are  areas.  melt  cited day  on  conditions  other  temperature, water  data  hydrometeorological  various  April  adopted  i n  A H  melt  under  departure  sun  predict  rates  (1915) r e p o r t e d 0.05 the  to  1964).  however,  estimating  the  A degree-day  melt  been  involved  value  temperature  the  air,  the  available,  mean  as  forest involved  from  necessary.  Utah  degree-day  1948).  the  energy  have  energy  seldom  evidence  from  rain.  of  are  rate  increasing  radiation,  the  Equations sources  in./day,  The  0.02.  with  of  transfer  from  of  of  wave)  heat  content  -0.002  of  ranges  evaporation.  sources  densation  low  approximately  influence  (short  vection  a  rate  Snow  The on  to  evaporation  decreasing  exceeds  Melting  the  by the  this  rate  per  Kittredge daily case  equivalent/degree-day  38  Examples of  t h e Cascade  Douglas  pine.  the open  well  i n Washington hemlock  a  greater  as a longer-lasting  inches  (1963),  water  o f forest  melt  working  equivalent  taken  depth  cover  were  (Tsuga  Measurements  show  Hart  as  Range  f i r , mountain  lodgepole i n  o f the effect  o n snow m e l t  provided  mertensiana after  i n three  by Griffen  (Bongo)  (1918) f o r  Carre),  t h e snow h a d j u s t  o f snow w i t h  greater  areas  and  disappeared  crown  density,  as  periods  i n New H a m p s h i r e ,  p e r degree-day  reported  f o r the period  melt  rates  March  i n  29 - A p r i l  12  follows. 0.16  —  open  0.10  —  hardwood  0.05 0.04  — —  f i e l d o f crown  area  white  pine  stand  basal  area  199  r e d pine basal  L u l l  stand  basal  a n d Rushmore  equivalent/degree-day  87 s q .  area  o f crown  s q .  stand  closure  90 p e r c e n t ,  closure  83 p e r c e n t ,  ft./acre.  reported  f o r hardwoods  24 p e r cent,  ft./acre  o f crown  229 s q .  (1961)  closure  ft./acre  and  melt  0 03 o  rates  o f 0.06 i n . w a t e r  f o r spruce-fir  i n the  Adirondacks. Sozykin watershed,  (1959)  north-west  less  i n forest  with  the rate  32.6  mm./day  than  (1.28  85 p e r o e n t  snowpack  have  i n open 16.7  in./day)  (1963) shade  a marked  on observations  o f Moscow.  averaging  Anderson but  reported  Accumulation  and the melt mm./day  season  made  a t t h e Moskva-Volga  averaged lasted  (0.66 i n . / d a y )  15  mm.  eight  (0.59 i n . )  days  longer  i n the f o r e s t and  i n the open.  reported i s nearly influence  that  maximum s h a d e  as e f f e c t i v e . on melt  results  Trees  but trees  i n least  to the south  to the north  melt  o f the  are only  39  12  per  cent  intercept absorb which  as  sky  radiation  direct  solar  reaches  radiation  effective  the  from  l n  preventing  and  protect  radiation  snowpack.  clouds  and  and  melt.  snow  because  radiate  Forests  to  of  that  the  the  this,  long-wave  reduce  atmosphere  Trees  but  the  of  do  they  radiation,  amount  reaches  north  also  some  of  long-wave  snowpack  at  night,  however. The may  be  sides  an of  trapping important  such  (Anderson,  winter  rate,  proceeds  likelihood timing  of  of  from  favorable  with  large  ably  and into  to  the  reverse  may  be  In  l i k e l y  best  land  i n  values  1.28  as  conditions  high  warmer  as  of  forest  snowmelt. than  or  heavy  and  with be  the  The  openings  down-hill  uphill  sides  true.  in./day  runoff  to  vary  stands being  between to  ripe  the  and than  0.16  recorded.  a  high  open  i n .  only of  i n . in  the  is  cold the The  influence  comes  early  forests  prob-  areas; i n  when forests,  forest  runoff  0.04  too  forest's  forest,  mix  from  of  snowpack.  warm p e r i o d  snowpack  ameliorate  likelihood  greater  the  change  Consequently,  rates  pine  from  the  transition  spring;  f i e l d  appreciable  i s  the  c r i t i c a l  both  slower  an  pattern  dense  i n  may  the  as  of  runoff  rain  When  greater  runoff,  swelling  runoff  use  snow  the  the  snow-melt  valent/degree-day  more  rapid  to  margin  winter  consequent  comes l a t e ,  summary,  delaying  accumulations  i s  down-hill  persists  unfavorable.  less  the  contain  snowpack  rainfall  snowpack  warm w e a t h e r  at  1958)•  temperature  contribute  the  the  heavy  high  air  always  and West  longer  melt  cold  mechanism i n  openings  Rice,  The rapid  of  and  open  conditions.  water open,  equiwith  40  3.  EVAPOTRANSPIRATION  Many studies have been made to determine the amount of water evapotranspired by different crops.  Investigations of water use by  forests have been carried out, using various methods, for the past 50 years, but due to the limitations of experimental techniques, results do not show a high degree of agreement.  Ideally, data would be available  on transpiration i n inches of water for each species, age, and sizeclass, but the problem i s very d i f f i c u l t for anything larger than a seedling (Kittredge 1962), Methods of Measurement Swans on and Lee (1966) discussed three techniques for estimating evapotranspiratlon:  (1) measuring the rate of vapor production of a  plant enclosed i n a plastic greenhouse, (2) weighing excised portions of plants to determine the rate of water loss, and (3) measurement of sap velocity by detecting the movement of heat, dye, or radioactive tracers. Tent method. In the plastic greenhouse, or tent, method, a pump i s used to inflate the tent which encloses the plant.  The difference i n  moisture content of outgoing a i r and ingoing a i r , combined with the rate of a i r exchange, gives a measure of the water loss from within the enclosure.  Because the water loss includes not only transpiration from the  sample plant but also evapotranspiratlon from the soil surface and lowgrowing shrubs, the same parameters are measured for a tent without an enclosed plant.  This value i s deducted from the f i r s t measurement to  41 obtain  an  estimate  However, the on  same the  i n  wave  the  being  much  the  of  the  i t .  causing  the  heat  the  tent,  of  tent  of  this  except i s  the  to  short-wave  of  not  the  rise  by  the  to  of  by  to  10  plastic  from  be  the  restricted  radiation  ground  l i k e l y  effect  is  to  radiation the  tree.  i s  effect  trapped  from  by  the  m e t h o d may  waterloss  by  test  be  enclosure  Quick-weighing  method.  and  off,  immediately,  An  i s  attempt  environment also  cuts  The from  piration  be  weighed  interval.  by off  cutting the  made  also  water  tent  air  15  degrees  tent.  The  than  to  long-  sun  or  sky  the  and  plant  ground  and  covered,  so  increase.  be  (U.S.  on  Dept.  i n  foliage  but with-  adjacent  i.e.,  the  at  In  method,  this  to  weighed keep  the  before  supply  so  the of  a  part  again  after  plant  in  excising. that  plant.  by  each of a  i t s  plant  short  the  here, differ  in  is  time  natural  may  only  site.  the  Cutting  which This  Even  plants  transpiration  tension  the  same  the  relative  plots. the  vegetation  that  the  although  are  all  1937)«  Agr.  measuring  effects  and  parts  the  to  useful  made,  releases  transpiring  plant  plants  suspending i t i t s  plant,  more  different  assumption must  requires  test  physiology,  back  energy  method  form  stop.  because  temperatures  radiation  an  part  method  greatest  short-wave  however,  and  sample  tent.  The  cut  the  this  plant  air  transparent the  from by  The  radiant  admits  evapotranspiration  rates  obtained  within  more  A variation within  value  tent  radiation,  traps  transpiration  naturally-exposed  combined with  plastic,  i n  a  the  environment  movement when  for  of  position  the  plant  would  soon  water  i s  cause  a  held  trans-  42 Rutter (1959) found that severed Scotch pine branches underwent a transpiration decrease of 12 per cent in the f i r s t 10 minutes after cutting, but that the transpiration rate of detached needles was not reduced during the same period. He reported that evapotranspiratlon rates determined by the weighing method agreed closely with those estimated by s o i l moisture measurements. However, as Swanson and Lee (I966) conclude, extrapolation from the part to the whole plant i s the most d i f f i c u l t problem with this method. Sap velocity method. Estimating evapotranspiratlon with this method depends on the relation of sap velocity and rate of evapotranspiratlon.  Skau and Swanson (I963) reported that f i e l d tests showed that  sap velocity i s closely correlated with the rate of transpiration from entire trees as determined by the tent method. Two factors complicate the use of sap velocity to estiraate transpirations  (1) The area through which the sap moves may vary with time.  I f this area decreases, for example, less water would be available for transpiration even though the sap velocity remained the same.  (2) The  amount of water within the sapwood may change^ i.e., even i f the conducting area remains the same, the moisture content of a given unit within that area may change.  The result i s the same as i n (l)o  These  problems could be resolved by making simultaneous measurements of the velocity profile across the sapwood and radial moisture content across the same area.  The sap velocity profiles can be obtained but Swanson  and Lee (1966) pointed out that a non-destructive method of obtaining the moisture content i s lacking.  43  Although limitations, single  change  rectly  an  determination  described  from may  used  i n  use  the  energy  of  the be  The  other  development  required that  a l l  i s  radiation NR  and  and  the  energy  loss  processed be  =  S  where  and  a  value  the  permits  may  air  the  at  by  + V  E  + K  +  for  of  =  net  S  =  heat  flux  V  =  heat  storage used  a  the  K  -  heat  E  =  latent  i n  heat  and  use  soil  transpiration  the  air  evapo-  be  the the  i s  l o c a rethe  the  l i q u i d  term,  to  evapomeasured. measure-  energy  radiation.  a l .  vegetation of  and  must  net  Goodell  input,  the  of  method  and  s o i l  of  et  and  particular  from  i.e.,  heating flux  This  energy  part  (Gray  the  in  on  i n d i -  theory  (1964)  radiation into  i n  the  simplified  that  equation  used  radiation  and  has  any  estimated  mentioned  surface,  NR  at  water  outputs,  radiometer  the  be  crops  l a s t  than  information  Fowler  to  from  i n  the  earth's  described  and  transforming  measurement  the  can  due  severe  cutting.  storage  stored  inputs,  net  provide  after  deducted  heat  be  evapotranspiration.  loss,  to  useful  m e t h o d may  budget  gain,  i s  has  (1961) d i s c u s s e d  Munn  energy  above  more  would  immediately  the  energy  of  This  estimating  obtain  prove  velocity  method.  attributed  To  may  method.  surface  the  described  Evapotranspiration  If  earth's  sap  rate  i n  time.  heating  state.  the  by  i t s  of  period  transpiration,  Net  transpiration  methods  methods  weighing  budget  vapor  budget  the  energy  the  difference  ments  example,  by  flection  the  of  method.  and  energy  three  budget  accounting  tion  the  Energy  evaporation  (1965)  For  with i n  of  combination  method.  conjunction the  a  each  I965)!  ii4  The small,  although  equation the  1962)<>  and Lemon by  above  important stands  part  may  flux  of  year  (Gray  be  heat  of  surface  i s  the  a l .  s o i l  I965),  relation  especially  has  been  evapotranspiratlon i s  not of  limited actual  cannot  be  expected  may  vertical  air  transpiratlon. concerning improved  invaluable  fluctuation motion Main  response  where  problems of  evapotranspiratlon  (Bruce  Clark  used  i n  other  Tanner  wind  as  where  in  daily  an  forest basis,  and  net  of  the the  radiation  s o i l  moisture  i960).  Pelton  as  information  net  combines  data  with  to  to  prove  availability  of  such  available. on  fluctuations  estimate  instrument  sensors.  How-  period-  out,  not  radiation  l i k e l y  moisture  is  i s  estimates  (1964) p o i n t e d  and h u m i d i t y i s  released  d u r i n g most  when  reliable  associated  method  hut  a  (Tanner  usually  where moisture  method  with  not  between  basis  Fowler  This  are  this  estimating  Soil  as  On  small  exist  dally  be  i s  i s  forest.  to  1964,  to  and h u m i d i t y  instrumentation,  and  but  method.  times  under  a  1964).  energy  energy  1965),  a l .  evapotranspiratlon  estimates  be  on  et  of  supposed  the  crops  relatively  shown  (Fowler  evapotranspiratlon,  for  agricultural  (Jeffrey  use  generally  value  greater  potential  i n  in  zero  considerably  l i m i t i n g  Eddy  a  than  (Gray  estimates  i c a l l y  higher  assumes  storage  photosynthetic  balance  A linear  ever,  the  be  that  heat  et  availability  may  also  Heat  into  and p o t e n t i a l  value  It  condensation.  assumes  evapo-  d i f f i c u l t i e s  However,  with  valuable  i n  is  limited  I966).  moisture  conjunction  budget. with  Changes  moisture  i n  input  soil by  moisture  storage  precipitation  and  have  outgo  been by  45  runoff, into  to  evaluate  and l e a k a g e  (Burroughs  and  and l e a k a g e Willardson  out  are and  piration  estimate. but  on  to  deep This  plots  evapotranspiration. that  percolation  vegetated  plot,  If  minimize plants  on  which  The  no  main  determined  Gravimetric been  used  for  resistance turbance  a  method  as  vegetation  not  are  will  water,  ignored when  Water this  of  be  i n  this  method i s  sampling of  permit  in  soil  estimating  the  prevent  out,  as  at  this  that  on  assumes the  be  must  added be  of  evapo-  sparingly  deep  enough  to that  that  evapotranspiration  i s  soil  moisture  encountered  in  cause  i n s t a l l i n g  has  site  which  l i t t l e  intervals  measurement  probe,  usually  periodic  Electrical  the  neutron  at  evapotranspiration.  with  are  to  estimation  must  moisture  determination  problems  seepage  covered  same  evapotrans-  conditions.  measurement.  years,  deep  of  source.  gravimetric  10  the  levels  does  past  the  amount  true.  used,  table  and  seepage  erroro  the  (1964) p o i n t e d  Jeffrey  necessarily  of  ignored  the  from  seepage  where  an  which  separated  than  the  by  measurement  of  cases  introduces  the  from  many y e a r s  blocks  terms  usually  rare  involves  loss.  f i e l d  those  are  be  advantage  under  studied  evaluation,  may  losses  water  such  seepage  irrigation  percolation  derive  suggested  denuded p l o t  i s  In  i n  these  stripped  the  being  Except  However,  percolation  transpiration,  area  omitting  (I963)  Pope due  the  1964).  equal,  l o s t  site  of  Shultz  moisture  same  evapotranspiration.  Access has  site access  with  less  tubes  become  widely  disturbance. tubes  in  for  d i s -  moisture used  in  However,  stony  soils  where  46 access with tractor-mounted equipment i s not p r a c t i c a l .  With hand-bored  access holes, problems include trampling of s o i l and vegetation at the s i t e and maintaining close contact of the access tube with the adjacent soil* Potted plant methodo  A simple method which has been used widely  i n the past to estimate t r a n s p i r a t i o n i s weighing a potted plant, allowing i t to transpire f o r a period, and reweighing i t .  The difference i n weight  i s due to l o s s of water and change i n weight of the planto  The plant  weight changes are so small r e l a t i v e to the l o s s i n weight by transp i r a t i o n that they may  be ignored and the t o t a l weight change a t t r i b u t e d  to t r a n s p i r a t i o n (Bonner and Galston 1959)° Lysimeters.  The use of lysimeters to measure evapotranspiratlon  i s described comprehensively by Pelton (1961).  With t h i s method plants  are grown i n tanks, and water l o s s from the tanks i s determined periodically.  Metal or p l a s t i c tanks are used having surface areas of several  hundreds of square f e e t and depths of eight f e e t or more. Lysimeters were i n use i n the 17th century f o r water percolation studies, but i t was not u n t i l the 18th century that they were used f o r measuring evapotranspiratlon (Gray et  a l 1966). 0  In 1906  the f i r s t  lysimeters with weighing devices were i n s t a l l e d i n Germany, and i n 1923 the f i r s t s e l f - r e c o r d i n g weighing lysimeters were constructed i n the United States (Pelton 1961).  More recently 5, lysimeters have been equipped  to record rates and amounts of runoff and percolation automatically (Dreibelbis 1963).  47  Lysimeters principles l i t h ,  or  of  are  of  three  construction:  undisturbed  s o i l  main  types,  classified  Ebermayer,  (1)  block.  f i l l e d - i n ,  (2)  (1961)  Pelton  according  described  and the  to  the  (3)  mono-  types  as  follows» In of  soil  the  l e f t  i t s e l f ,  be  The walls,  an  in  in  situ.  used  to  determine  are  usually  natural  of  soil  are  used  measured  by  probe),  or  method,  the  changes  on The  to  i s  the  large,  water  floated  manometer  chief  soil  and  no  are  is  of  a  placed  walls  container  that  f i l l e d as  with  applied,  for  has in  and  under  a  block  cannot,  in  sampling or and  a  a  natural  (e.g.,  hydraulic  et  such  stripped  a  manner  side  These from  that  the  they  casing open  and  i n  moisture  gravimetric  weight  around  a  bottom.  changes  Soil  methods.  in  built  In are  s o i l may  samples the  or  moisbe neutron  hydraulic  recorded  as  pressure  1966).  a l . the i s  vertical  percolation.  been  partly  outflow,  changes  with  possible.  composed o f  against  profile  i s  side  provides  s o i l  nearly  determination  lysimeter e.g.,  (Gray  argument  funnel  evapotranspiration.  moisture  i s  evapotranspiration tween  as  using weighing  tank a  of  with  provided  determine  direct by  and  that  They  lysimeter  Measurements ture  f i l l e d  conditions  has  consists  bottom  layers.  monolith  block  a  percolate  evapotranspiration.  and  top,  a  lysimeter  open  The natural  The  lysimeter  structural  approach  type,  f i l l e d - i n  lysimeters area  Ebermayer  use  that  of  there  conditions.  and moisture  the  lysimetric  may  The  be  scope  regimen,  method  differences for  plant  such  rooting  of be-  differences  48 character! sties j, methods of water application, and the net energy exchanges  However, i f the installations satisfy certain minimum standards  B  they w i l l provide reasonably reliable estimates of evapotranspiration over short time periods (Linsley et a l . 1949  9  Pelton 1961).  The minimum standards that should pertain are?  ( 1 ) the lysimeter  should contain soil that has been disturbed as l i t t l e as practicable*) . (2) uniform conditions around the lysimeter should be maintained and 9  (3) the ratio of the area of surface occupied by lysimeter walls to the enclosed area should be made small. Results of Investigations The Tennessee Valley Authority determined that total transpiration from a forest of pine, oak and other shrubs from May 19 to October 1 9  was 420 mm  0  s  (16,5 in°) (Rothacher 1949).  9  The method used was the placing  against the growing leaf strips of f i l t e r paper that had been soaked i n a solution of cobalt chlorideo  The time required for colour changes to  take place as moisture was absorbed by the f i l t e r paper was compared to a standard to obtain an estimate of transpiration. Oelkers (19^Q  8  cited by Penman 1963) i n Germany, used lysimeters 9  to determine transpiration for a growing season of 153 days on a. medium pine site. fir  9  He reported the following values:  66 mm. (2.6 in.); bireh 74 mm 9  0  pine  9  80 mm. (3<>2 i n . ) ;  (2<>9 in.); larch (Larix s p ) 0  B  147 mm. (5°79 in.)? and spruce, 323 mm. (12.7 i n . ) . Using a set of large lysimeters at Gas tricum* Holland Dei j (195^9 9  cited i n Penman 1963) determined that conifers had a mean annual  49  evapotranspiratlon for the period 1948-1953 of 538 mm. to 417 nwo (16.4 in.) for deciduous, and 448 mm.  (21.2 in.) compared  (17»6 in.) for low  vegetation. Smirnov and Odinovkova (195^), working on aspen i n the Tellerman Forest i n Russia, reported transpiration of 203 mm* year old aspen; 230 mm.  (7»99 in.) for eight-  (9«06 in.) for 25-year old aspen; 201 mm.  for 36-year old aspen; and I 8 5 mm.  (7«91 in.)  (7«28 in.) for 63-year old aspen.  These  figures were arrived at by calculating a water balance using evaporimeter measurements, throughfall, soil moisture, runoff, and i n f i l t r a t i o n . Straight-line relations were found between the amount of transpiration and the current annual volume increment of the stand. Holstener-Jorgensen (1959) reported water use by 65-year old beech and 45-year old spruce on the Danish Forest Experiment Station. The author used ground-water levels, which, i f they reach the zone of root activity, may be used to give a measure of water use.  For the  period April 19 - December 14, 1956, beech transpired 48lmm  0  spruce transpired 471 mm.  (18.94  inc.);  (18.5^ in.) for the period April 15 - December  13» 1956; and for April 10 - December 28, 1957, beech 417 mm. and spruce, February 28 - December 28, 1957, 469 mm.  (16.42 in,)  (18.46 i n . ) .  The  order i s reversed for the two years which might be accounted for by a difference i n response of the two species to changed availability of water i n the two years, but more l i k e l y i t i s that because of the mild spring or late winter the spruce began transpiration several weeks before the beech i n 1957=  Molchanov  cited by Penman I 9 6 3 ) used soil moisture deter-  ( 1 9 5 5 »  mination to estimate water use i n an area where mean annual rainfall 500 mm.  ( 1 9 c ? in,)«  was  The maximum values of evapotranspiratlon were as  follows % Scotch pine (Pinus sylvestris L,), 40-80 years, 420-467 mra, (I60  5-18,4 in,)  oak, 40-100 years, 443-469 mm. (17 = 4-18,5 tn„) ash, 40 years 416 mm= (16,4 in,) aspen 20 years 392 mm, (15<>4 in,) t  g  9  Molohanov ( i 9 6 0 ) concluded that evapotranspiratlon was greatest in larch, followed by f i r , pine, oak, aspen, ash, and birch standsc Wtihin a given species the water use varied with age, the highest use being observed i n the period of culmination of current annual volume increment.. Kittredge (1948) also indicated that there i s evidence that transpiration i s greatest for dense stands on the best sites at the culmination of current annual increment. Brown and 'Thomson (I965) measured soil moisture i n spring and f a l l of 1955* 195?9 1 9 5 8  s  i n Colorado to determine water use.  The study  indicated that water use per day was greatest on aspen sites, intermediate on Engelmann spruce sites, arid least on grassland sites.  There i s reason  to believe t h a t i n aspen and spruce types the water use would be similar under conditions of similar soil moisture* since the moisture with.dra.wn by aspen exceeded that of spruce by almost the same amount as the differences i n spring s o i l moisture under the two types.  51 The evapotranspiration from spruce-subalpine f i r forest i n the eastern Rocky Mountains of Alberta» was estimated by the eddy-flux method (Munn and Storr 196?)«,  Measurements of net radiation above the canopy  and of gradients of wind and temperature from an 80-foot tower were taken.  Fast-speed runs of the fluctuations of temperatures, humidity  9  and vertical wind were taken using dry and wet bulb thermocouples and a vertical anemometer. Evapotranspiration was estimated to be about 0 3 o  grams/cm. or Q 13 inches/day. 0  Rutter (1959) related evapotranspiration to solar radiation. The trends over time of both variables were quite similar. In 1928 Meyer constructed a graph from which the depth of transs  piration could be read directly from mean monthly a i r temperature. A l though factors other than a i r temperature were neglected^ the results were not dissimilar to those obtained by other methods. - Considering the important influences of meteorology and s o i l moisture as well as the influence of vegetative factors such as the type  9  colour^ density;, and shape of the plant on evapotranspiratdong, few detailed conclusions seem warranted regarding the amount of water use by trees.  There i s evidences, however which seems to indicate that i n 9  both conifer and deciduous stands there i s an increase i n water use until about age 60, with a gradual dropping off after that age.  The range of  evapotranspiration for most species i s about 300 to 500 mm./year (roughly 10 to 20 in./year).  52 4„  STREAM FLOW  Annual Disoharge Investigation of the hydrologic role of forests has often been directed toward streamflow measurements,  Of the elements of the hydro-  logic cycle, surface runoff i n channels i s the easiest to measure. This, along with the importance of quantity and timing of runoff has 9  been responsible for the accent on stream gaugingo integrator of a l l the variables on a watershed.  Streamflow i s the  Because of this, water=  shed treatment has been assessed by i t s influence on streamflow,, Of the factors of the water balance that might be amenable to influence by man, evapotranspiratlon seems to be the most readily altered. Rakhmanov (1959)» reviewing the literature of the past 100 years, concluded that forest cover does not accelerate evapotranspiratlon, and that there i s no substantial difference between forest and other c u l t i vated land areas i n similar environments.  However, this view i s not  widely accepted, as a review of the literature will indicate. In Japan, clearing of broad-leaved trees, 30-feet t a l l , caused greater streamflow surges immediately after rain, and a reduction i n annual water use, the increase i n quantity of runoff being similar to the estimated interception before cutting (Hirata 1929)o One watershed of a paired-watershed experiment i n Kamabuchi, Japan, containing mixed conifer and broad-leaved deciduous trees, was clear cut, grass and brush regrowth being removed i n each subsequent year.  Runoff  during the succeeding three years averaged 1790 mm. (70<>47 in.) from the  53 forested  watershed  difference,  165  mm.  piration  the  bare  on  In  the  Switzerland, forested  watershed  grassland.  must  be  covered from  and  et  the  and  attributed and  to  greater  caution  because  one.  reduced  runoff  that of  bare  watershed  evapotranspiration suggested  the  The  evapotrans-  1956).  Inose  Rappengraben  reported  (1958)  Bramke  respectively,  from  from  was the  studies the  greater data  least from  from  doubts  about  cent  greater  i n  woodland  this  the  study-  accuracy  of  streamgauging.  a l .  forested  was  in.)  (1963)  heavily-forested Lange  and  that  with  (76.9?  (Maruyama  (195*+) and  approached  the  site  Penman  raingauging  from  in.)  (6.50  Burger  Delfs  rom*  Sperbelgraben  than  the  1955  and  10  reported  Wintertal  watershed  i n  per  watershed  Germany.  1948-1953  for  the  and  i n .  respectively  28  the  clear-cut,  Precipitation  watershed 48  than  evapotranspiration  period  for  the  and  49  were  grass-  runoff and  23  grass-covered  i n .  water-  shed. At cleared  Wagon  and  f i r s t  was  three  cent  greater  year  period  Gap  about  years  runoff runoff  was  only  difference  the  vegetative  recovery  of  one  Coweeta  watershed  of  aspen and  per  the  i n  a  similar  invading  was  about  6  watersheds  the  area.  i n .  annually.  watershed  had  23  for  the  greater.  The  assumption  23  area in  to  18  (Bates North  increase  of  second  For per  threei s  per  cent,  was  and  Henry  1928).  Carolina, 16  i n .  due  the  where  was  Annual  watershed;  Forest  runoff  two  treated  from  treated  Experimental  resulted  the  cent  runoff,  of  quickly  untreated 18  i n  one  runoff  cutting,  the  decreasing  the  i n .  after  than  Colorado,  with  21  the  At  i n  slash-burned,  precipitation the  Wheel  that to  cutting  pre-treatment  54  yield averaged about 30 in« (Hoover 1944), Removal of vegetation from 30 per cent of a 250-acre watershed on the H J. Andrews Experimental Forest, i n Oregon, caused a 12-28 per cent U  increase i n minimum streamflow.  Removal of timber on 40 per cent of  another watershed increased low flows by 45 per cent, and by 85 per cent after 80 per cent of the watershed had been logged.  Annual water yields  before treatment were from 50 to 60 i n . and annual precipitation averaged 94 i n . (Rothacher 1965a). Twenty years of before-and-after records on the Pine Tree Branch watershed i n Tennessee indicated that total runoff decreased from three to six inches per year while ground-water runoff volumes remained unchanged after reforestation  r  Mean annual runoff for the 20-year period  was 10 i n . Peak discharges i n both summer and winter floods were reduced by ?0 to 90 per cent for moderate to large storms (T.V.A. 1962).  Up to  five inches of increased runoff (increasing the annual yield to 26 in.) resulted from clear cutting watersheds i n the Fernow Experimental Forest. Evidence indicated that fully-stocked stands were a benefit to flood control during the growing season (Reinhart et  a l . I963).  Evidence reported by Rich (19&5) indicated that the type of cut, not just the basal area removed, influenced the runoff from Workman Creek watersheds i n Arizona.  No significant increase i n water yield resulted  from a riparian cut on the North Fork, but only 0,6 per cent of the total basal, area was removed.  A later clear cut of moist-site vegetation along  the streams, amounting to 32 per cent of the area, did result i n increased water yields.  However, removal of 24 per cent of total basal area by  55.  single-tree  selection  fire  South  on  y i e l d  the  during  the  from  to  26  state,  Fork  and  84 p e r  another  since  significantly  has  the  cent  not  on  construction increased  and water  cut.,  Shackham  reduced i t s  road  by  significantly  (1961) r e p o r t e d  Ayer  cent  per  21  watershed,  years  11  Schneider  and  Brook  mean  that  increasing  watershed,  flow  over  the  forest  i n  central  26  years  cover  New  York  following  treatment. Hewlett out  over  the  Carolina. at (1)  (2)  years  30  are  at  the  some o f  Coweeta the  the  watershed  studies  carried  Hydrologic Laboratory,  conclusions  that  have  been  North reached  Coweeta: Five  to  year  after  South  When  have  i n .  16  of  have  on north  treatment i n  increased  the  yielded  slopes effects  timing  of  have  half  the  been measured i n  the  f i r s t  been l a r g e ,  part  of  the  which  the  actual  savings  increase  would  be  i n  f i r s t  year  there  has  increases  ob-  treatment.  have  small,  the  increased  tends  terms  to  of  be  been  runoff.  When  during that  reduced  considerable effects  season  i n  evapotranspiration  expected.  When i n c r e a s e s  season.  only  after  been  years,  runoff  clear-cutting.  slopes  delay  (4)  past  (1961) r e v i e w e d  Hibbert  Following  tained (3)  and  but  most  are of  large, the  they  increase  extend comes  over  a period  during  the  of  winter  35-^0 (high-flow)  56 First-year  (5)  of  the  A  at  Coweeta  riparian-strip  watershed  did  not  basal  area  cut  i,e.,  0,15 ( r a n g i n g  which  was  cuts  also  range Some  ested are a  from  Sokolovsky  runoffcoefficient while  spring  the  Vorony  0,54;  runoff  of  i s  the  i s  0.13  to  a  that  of  ( i » e . ,  0.27,  nearest  f i e l d 90  per  compared  generally  forested  some  factors.  other  that  Increases  proportion  i s  of  of  per  pattern  yield  the  basal i n  cent of  increase, area  annual  f i r s t » y e a r  of  increase  four  excluding  the  riparian-strip  slope.  The  ratio  one  y i e l d .  the  smaller  to  due  watershed, per  cent  to  northerly  for  south  O.56  for  the  less  per  slopes, cut slope  watersheds  runoff  increases  1959)«  (Sokolovsky  watershed  results  may  directly  related  to  Whatever  factors  may  per  cent  had  be  to  as  the  Petrushino.  trees. sq.  for  was  of  forested  forested  the  elevation, explain  the  had  coefficient  coefficient  reason  that  a  77,000  the  The  had  from  of  examples  forested,  watershed,  runoff  f o r -  precipitation  a  f i e l d  (116  from  following  the  transpiration  runoff  The  Usadjevskyj,  forested,  for  98 of  cent  to  annual  watersheds.  27  accepted  moisture  most  the  the  for  watershed,  indicate  of  The  increase  same  report  Tajeshny  to  contradiction  cent  ratio  the  (1959)*  Russia  watershed  the  to  to  0.07.  medium and l a r g e  the  related  removedo  per  northerly  on  of  be  relation  0.17),  to  observations seem  i s  from non-forested  of  to  significant  investigators  0,29  loss  a  approximately  watershed,  The. r e a s o n sheds  point  from  watersheds than  runoff) of  Russian  that  l i t t l e  produce  is  0.00  stand  seem  r e m o v i n g 12  conducted on  from  yield  showed  cut,  An i n t e r e s t i n g cent  i n  fully-developed  cutting (6)  increases  waterHowever,  mi.)  i n  proportion this  increase  seeming i n  precipitation, conclusion  or  reached  by Sokolovosky, much evidence indicates the opposite to be true. In summary, runoff i s greater from grassland than forest, and annual runoff has usually increased after clear cutting, increases commonly being about 25 per cent with extremes of nine and 85 per cent being recorded. Flow Regime The effect of cover changes on streamflow would not be expected to be constant throughout the year but to vary with season as other factors vary (e.g., transpiration).  Studies have shown that cover changes do  alter the regime as well as total flow of streams. Wagon Wheel Gap Colorado. t  At Wagon Wheel Gap i n Colorado, partial  cutting of a 200-acre watershed resulted i n spring runoff beginning earlier and higher peak flows (Bates and Henry 1928).  o San Gabriel River. California. ern  On the San Gabriel River i n south-  California f i r e burned over the Fish Creek watershed but missed the  adjacent, and. similar, Santa Anita Creek watershed.  Peak discharges  from the Fish Creek watershed were much greater i n the f i r s t year after the f i r e , but f e l l progressively i n succeeding years (335» 292, 145, 15» 11, and 11 c.f.s./sq. mile) as vegetation regrew on the watershed.  With-  i n six years, runoff from the watershed was back to normal (Hoyt and Troxell 1934). Coweeta, North Carolina. watershed was cut over i n 1941.  At Coweeta, North Carolina, a 33-acre The average monthly streamflows for the  following 15 years was higher than predicted, with the September-December  53  period per  (normally  cent  Tennessee,  Tree  reforestation  H.J.  the  years  process three the  In of  the  crease  cutting  minimum  On  a  an  per  cent  per  normal  for  by  over  90  Pine  Tree  Branch  watershed  reduced winter  and  i n  summer  the  the  H.J.  cent  of  The  was  in  on  area  Oregon.  a  recorded, there  Forest,  on  After  ft.  elevation, was  clear  was  cut.  but  f i r s t  the  a 12  to  i n  next  maximum six  28 p e r  i n  the  studied  The  i n  for  seven  was  cleared  No i n c r e a s e  was  re-  250-acre w a t e r s h e d  streamflow  was  burned.  treatment  western  watershed  effect  (1965a)  Experimental  3,500  and  the  the  Rothacher  watershed,  1,500  of  Andrews  Range  adjacent  Oregon.  for year  flows years  cent  i n -  flows.  when 40  1963 per  cent  terms  the  Forest.  broadcast  second watershed  began i n  i n  Cascade  watershed  i n  absolute  flows  was  beginning of  45  at  between  per  25  area  1964 u n t i l 80  creased  markedly  construction.  treated  the  resulted  with  eight  then  being increased  On  the  region,  road  years,  after  of  1959,  clear-cut  from  i n  f i r  flow)  Tennessee.  studies  calibration  treated.  i n  slopes  Douglas  lowest  Experimental  on watershed  of  of  1962),  (T.V.A.  Andrews  western  the  Branch*  discharges  ported  period  1959)•  (Meginnis  Pine  peak  the  cent and i n  but the  the late  of  i n  the  per the  1964,  H.J.  cent area 85  Andrews of  was  per  months.  cut.  cent.  high percentages summer  the  are  Experimental  area In  was  cut,  I963,  low  The i n c r e a s e s due  to  the  Forest  and  continued  flows were  i n small  extremely  low  59 Fernow Experimental Forests West Virginia.  On the Fernow Experi-  mental Forest i n West Virginia, studies were carried out on watersheds supporting stands of deciduous species, vizo, oak,, maple (Acer sp ) 0  beech cherry (Prunus spo) 9  s  and poplar.  Significant increases i n stream-  flow during the growing season were recorded for three watersheds one a  clear cut one cut to diameter l i m i t a  9  and one cut on an extensive  selection basis (harvesting and k i l l i n g of culls larger than 11 i n . dsboh.)o  The increase i n discharge appeared to be greater with the more  severe cut.  Large increases i n flow were not recorded during the  dormant season (November-April).  Instantaneous peaks on the clearcut  watershed were increased on the average, by ZL per cent i n the growing 9  season and reduced by four per cent i n the dormant season (Reinhart at a l . 1963)o Fraser Experimental Forests Coloradoo Forest i n Colorado  9  At the Fraser Experimental  streamflow records were kept for 12 years before  cutting the 714-aere Fool Creek watershed i n 1954 (Goodell 1958).  The  25O- to 30Q-year-old stands of lodgepole pine and Engelmann sprucesubalpine f i r were logged i n clear-cut strips so that 278 of the - 550 ,. forested acres were cleared (Love 1960)  o  In the eight years since the  cut, average annual streamflow has increased by 2.7 area-inches or 25 s  per cent (Goodell 1964)  0  Howevers> nearly a l l of the increased flow  occurred during the spring runoff period and low flows were increased l i t t l e (Hoover and Shaw 1962).  I t i s estimated that increased yield  w i l l continue for 35 to 50 years before regrowth reduces i t to zero (Goodell 1964)o  6o Spring flood peak was greater the f i r s t year and 23 per cent less the second year than predicted values.  The author suggested that the  effect of clearing may be to decrease or increase peak flow depending on weather conditions (Goodell 1958). Shackham Brook, Central Mew York.  Reforestation of three water-  sheds i n central New York state resulted i n dormant-season runoff being reduced 0.17 to 0.29 i n . per year, averaged over the 26 years since treatment.  For Shackham Brook watershed, runoff was reduced by 0.14 i n .  for the growing season, 0.23 i n . for the dormant season, and O.36 i n . for the year, and peak discharges by 41 per cent for the dormant season. No significant change i n peak flows for the growing season nor annual low flows were recorded for any of the watersheds (Schneider and Ayer I96I). In summary, the effects of clear cutting on flow regime vary with climate, soils, etc. The literature reviewed indicates that peak flows increased l i t t l e to as much as 21 per cent and low flows l i t t l e to as much as 90 per cent. Snowmelt and' Water Yield Snow accumulation and melt have an important influence on water yield and regime but less attention has been paid to this aspect than to accumulation i t s e l f . In 1935» Gonnaughton concluded from a study carried out i n ponderosa pine i n southern Idaho that forest-cover conditions affected snowmelt and that retarding the rate of melt by forest management could, increase the  duration of runoff and distribute the peak flow over a longer time. 1  In the White River drainage basin i n Colorado, 226 sq. mio( of i  Engelmann spruce and lodgepole pine were killed by the Engelmann spruce beetle.  The resulting increase i n snow accumulation increased streamflow  by 22 per cent with peak flows coming i n June instead of May as they had before (Love 1955). i Other studies on snow accumulation and melt have been reported i n a preceding section on sriow, and Colraan (1953) has summarized the l i t e r a ture on the subject to 1953*  The results of most of these studies  indicate that forest-cover reduction usually increases snow accumulation as well as melt rate.  This, i n turn, produces greater water yield and  higher peak flows. Reinhart et  a l . (1963), however, reported from limited observations  that daily snowmelt runoff from a clear-cut watershed i n West Virginia was for one 14-day period more uniform than from the forested, control watershed.  The period was March 18-30, i960, during which flow from the clear-  cut watershed was only 92 per cent of the control.  On March 30, peak  flows were recorded on each watershed and the flow from the clear-cut watershed was 71 per cent of control.  The explanation suggested by the  authors i s that, snow cover disappeared near the end of the 14-day period and that i t was gone on the clear-cut watershed before the control.  Appar-  ently, exposure of the snow cover resulted i n a much lower peak. Eschner and Satterlund (I963) stated that timber harvesting may increase or decrease, depending on weather conditions, not only peak flows,  62 as suggested by Goodell (1958 )  9  but the entire period of high winter-  spring runoff. A study by Satterlund and Eschner  (1965)  indicated that the average  rate of concentrated runoff during snowmelt appeared to be faster after reforestation of Shackham Brook watershed i n New York state.  The reason  given i s that runoff from the forested watershed, though reduced i n quantity was even more concentrated i n time.  "If we accept the well-  demonstrated fact that the rate of snowmelt per degree day i s less i n the forest than i n the open" (Satterlund and Eschner  1965»  p» kOk), the con-  centration i n time can be explained. As spring days pass the number of degree-days increases rapidly. Before this rapid increase, snowmelt has been slower i . e , the snow i n 9  0  the open, which melts before that i n the forest, has melted at a slow rate due to the slow increase i n degree-days.  The snow i n the forest i s  then subjected to the greater amount of heat per day causing? faster melt rates than occurred i n the open.  Along with this i s the greater possibil-  i t y of a rain on snow event the longer the snow remains. The authors suggested that the relation between forest and snowmelt under the climatic conditions of the north-eastern United States may be •i  different where a uniformly cold winter climate prevails.  \ \  5«  EROSION  The terms normal and geological erosion refer to natural erosion which includes the processes of s o i l formation and s o i l erosion, and  63 which Soil i s  occurs loss  through  i n  usually  excess  and  erosion  of  interest  that  amenable  The by  man  land  because  Eroded and  i s  desire  that  has  homes.  aquatic  damage  to  pumps,  often  cause  rients  and  the  Falling lands.  For  to  Neff  1963)9  the  1940)o obstacle  These  soil  l i f t  a  drops  foliage  and  to  f a l l i n g  rain.  cover  Leaf  l i t t e r  reaches further  the  up  the  i t  the of  or  s o i l  i s  The  this  of  has  been  type  of  and  lower and  raised  also off  stream  include  the  one  hour  of  two  held  impact  ..  quality,  plant  which nut-  offer and  less and  on which  imparts  feet  miles  vegetation not  the  s o i l .  i n  i s  i s  bottoms  the  f a l l i n g  20  structures  irrigation.canals,  surface  to  productive  deposited,.  water  the  up  a l l ,  which  to  of  incurred  engineering  reservoirs  considerably  force  f i r s t  sediment,  form  losses  energy  the  which  the  to  top-soil layer  speeds of  by  washed  rain  ground with  reduces  moves,  Losses  tremendous  Rain  erosion,  aLo 1955)°  et  of  material  pipelines,  branches  result  caused  damage.  reaching  cover  because  include,  i t  take  seven-inch  The  this  losses  two-inch  the  as  particles  imparts  (Frevert  the  eroded  s i l t i n g  flood  i s  damage,  and  glacierso  accelerated  natural  erosion  losses  losses  turbines,  example,  energy  erosion  the  wind  i n  and  efforts»  These  habitat,  rain  ient  control  upon which  are  finer  and  gravity,  termed  changes  accelerated  causes  increased  of  i s  erosion.  wind,  erosion,  water  control  or  waters,  by  to  erosion.  to  result  man's  also  damage  the  to  eroded  of  geological  here  Secondly  of  action  caused  of  material  product  of  considered  conditions  i s  the  the  hour  driving  and  (Laws  f i r s t  evaporated  absorbs  s u f f i c -  (Robins  per  i t  by  force. water.  64  Roots s o i l  and  the  porosity  stems  reduce  infiltrate the  the  to  has  soil of  often  drier  tions,  that  decadence probably  Erosion  The of  twigs,  cutting  of  water  erosion Near  climatic  those  human  (Robins Eastern  evidence since  was  erosion  the  but  to  that  been  for  suggest  of  the  played  a  a  not  of pre-  c i v i l i z a -  by  has  cutting as  not  those  as  in  the  become  c i v i l i z a -  denudation  part  this  i s  suggested  climate  existence  does  part  African  hillsides  the  plant  1963)0  North  the  responsible  and  water  Neff  often  certainly  civilizations,  flowing  and  that  increase  an i m p o r t a n t  and  of  have  that  i s  because  changes  regions  activity  resulting  This  deforestation  (1953) c i t e d  in  action  erosion  of  to  vegetation  Litter,  overlando  soil  vdth  infiltration*  on  decline  associated  of  the  the  the  cause  is  warranted.  Studies f i r s t  which  to  compare  China  i n  the  cultivated watershed forested  soil-erosion  study  vegetational  influences  1920"s.  land study  than i n  watershed  m.2/km. /year  third  flows  been l a i d  those  not  The  145  the  although  noticeably  hillsides.  but  and  vegetation  Lowdermilk  and  faster  velocity  for  grazing,  causeo  activity  significant  Blame tions  allowing the  influence  requisite  and  biological  2  forest  and  Runoff on  forest  Emmental, was (20.7  and  85  cu.  two-thirds  0  which  erosion  land  average  m ^/km  i n  0  2  on  rates  sediment (12.1  ft./acre/year) (Burger  were  obtained  e r o s i o n was were many  (Lowdermilk  /year  pasture  data  1953)«  load cu.  from  from  carried times In the  the  out  cited  i n  on  Swiss  almost  watershed  i n  greater  ft./acre/year)  the  1943;  with  of  Penman  wholly-  and one1963).  65 The  sediment  from  the  forested  In land  was  study  production  watershed  Michigan, from  the  Smith  to  500  following Forest Wild  from  —  the but  and  the  sediment —  —  that  —  .  —  Cultivated  North i t  Carolina,  would  take  (1953) r e p o r t e d  Erosion  to  crops.  Land  tinuous  cropping of  Watershed  in  badly  activities  result  i n  44  from  In  another  Michigan  measured  "  results  layer  a  1964):  mi.  study  terms  of  topsoil take  years;  cover  natural  96.000  ( S t r i f f l e r  " of  i n of  arable  "  cropping would  grassland,  Sixteen  study  of  annual  of  land  and  years;  the  erosion causes  at  the  the  under  under  trees  and under  of  years  different  18 y e a r s ; of  Statesville,  number  con-  burned  unburaed  range  some  such  precipitation  grass  i n  northern  lands  degree.  erosion,  construction i n  slopes,  and  land  (Wallis  soil-holding influence  selected  s o i l s ,  sediment  to  of  road  to  slumping  decrease  watersheds were  cover  Mean  gullied  and p o o r  conditions  a  forest  that  prevailing i n  of  among t h e  over-grazing,  1965)»  without  accelerated  (1955) i n c l u d e d f i r e ,  2,200  seven-inch  cotton,  conversion  resulted  tion  a  small.  "  "  Station  very  over forest,  years.  The has  fallow  1,800 y e a r s ;  annually,  500,000  i n  erode  Experiment  s t i l l  that  erosion  11  1,800  the  double  that  lb./day/sq.  741  —  were  almost  was  forest.  rates  360  —  Pasture  Lowderndlk  from  was  amount  (1952) f o u n d  discharge  land  watershed  absolute  Crabbe  times  1,000  —  pasture  surface varied  careless  1965)* of  et  vegetaa l .  logging,  methods.  northern  erosion, water  GELeason  California  Mississippi  land  yields  between  51  use,  and  (Ursic  and  5^  to  plant  and  i n .  represent  Dendy  for  the  66 different vated  land,  pine  5;  watersheds  plantation, yields  pasture,  1.61;  plantation, data  are  increases  Erosion  the  results  factors  of  w i l l  i n  to  the  per  as  fields,  75  depleted  year:  Anderson  on  cultivated  and  c u l t i -  hardwoods,  soils,  21.75;  land,  s o i l s , except  9°  pine  0.10;  The  0.02. for  the  mature  1960-1961.  shown  stand  was:  hardwoods,  shallow  years  have  forest  shallow  1959-1961,  years two  on  depleted  0.13;  studies  the  be  indices  other  the  has  by  the  the  erosion  been  that  and  erosion  factors,  the  relationship  density  Trobitz  decreases,  19^9»  Anderson  between erosion  195^»  the  influence  climate  vegetation. hazard  and,  amount  of  hazard  have  such  hazard  a  of  been  A change unless  sediment  the  on  would  in  modified  any  of  compensating produced.  objectives  rating  s o i l ,  be  of  changes  Means  many  helpful  these  of  studies.  i n  managing  erosion.  d i f f e r which  i n  s o i l  evaluated of  from  topography  change  minimize  method  might  many  inches  Ratings results  Soils A  for  19*+9»  Erosion  hope  land  three  cover:  (Anderson  estimating The  was  of  forest  Hazard  factors occur  which  tons  pine-hardwood  the  i n  1962).  T.V.A.  by  for  runoff  pine-hardwood  f i e l d s ,  mature  0.02;  and  i n  abandoned  pine-hardwoods  erosion  mature  1;  annual  abandoned  15;  averaged  averages  The  average  pasture,  16;  Sediment  but  erosion,  was the  their  propensity  characteristics proposed  by  dispersion  to as  erode, they  i.e.,  their  relate  to  Middleton  (1930).  He  ratio  the  and  erosion  erodibilityo  erodibility developed ratio.  two  6? The dispersion ratio i s the ratio of the amount of s i l t plus clayi n the s o i l , determined without chemical or mechanical dispersion, to the amount of s i l t and clay determined after standard dispersiono  The  erosion ratio i s the dispersion ratio divided by the ratio of colloid percent to moisture equivalent,.  Middle ton classified erodible soils as  those whose dispersion ratios were greater than 10 and whose erosion ratios were greater than 15°  Non-erodible soils had ratios below these  values, Anderson (1951) used the erosion ratio and the dispersion ratio , in conjunction with other s o i l characteristics and forest cover density to estimate sediment i n streams.  He reported that both ratios were  useful indices of soil credibility, but that the dispersion ratio was the better index.  His study also showed that forest cover density had  a highly significant influence on erosion, Andre and Anderson (1961) related the surface-aggregation ratio and dispersion ratio, as indices of erodibility, to geology, vegetation and elevation. The surface<=aggregation ratio i s (the amount of surface i n square cm,/gm, on particles larger than s i l t ) divided by (the total percentage of s i l t and clay i n dispersed soil minus the percentage of s i l t and clay i n an undispersed s o i l ) , i,e», the ratio of the amount of surface i n the non-binding fraction to the amount of clay i n the,soil. The study indicated that the surface-aggregation ratio was more significantly related to s o i l erodibility than was the dispersion ratio. Also shown by the study were, (1) soils developed from acid igneous  68  rook were about Zj times as erodible as s o i l developed on basalt, (2) e r o d i b i l i t y was highest f o r s o i l s under brush, next under trees, and l e a s t under grass, and (3) no d e f i n i t e r e l a t i o n o f e r o d i b i l i t y to elevation was shown. Analyses o f texture and p o t e n t i a l e r o d i b i l i t y were made on samples o f f o r e s t s o i l s from 6,500 to 8,000 feet i n the southern Sierra Nevada, i n C a l i f o r n i a (Willen I 9 6 5 ) .  Texture and e r o d i b i l i t y were  r e l a t e d by regression analysis, to rock type, cover type, elevation, aspect, and slope.  S o i l texture was found to vary widely with rock  type, as d i d aggregated s i l t and clay.  S o i l texture was l e s s  signifi-  cantly related to vegetative cover but aggregated s i l t and c l a y was highly s i g n i f i c a n t l y related to cover type. Middleton's dispersion r a t i o and Anderson's surface aggregation r a t i o were used as indices o f p o t e n t i a l e r o d i b i l i t y i n Willen*s study. The dispersion r a t i o was s i g n i f i c a n t l y related only to parent rock type.  S o i l s developed from granodiorite were, based on the dispersion  r a t i o , more erodible than those from basalt, and those developed from quartzite were l e a s t erodible.  Based on the surface-aggregate r a t i o ,  the sequence was granodiorite with the highest p o t e n t i a l e r o d i b i l i t y , followed by quartzite and basalt. Potential s o i l e r o d i b i l i t y was greatest f o r s o i l s under grass, followed by brush, pine, and f i r .  West slopes were more erodible than  south slopes, followed by north and east slopes.  S o i l s a t high eleva-  tions were more erodible than s o i l s o f the same derivation a t low elevations.  69  Wooldridge (1965) used mean aggregate size as an index of erosion on b a s a l t i c  soilso  He found this index a good guide i n assessing  erosion hazard, due to i t s s e n s i t i v i t y to changes i n vegetative cover and i t s strong r e l a t i o n to organic matter content, bulk density^ and porosityg, s o i l properties known to be related to s o i l t i l t h and struetureo Anderson (1949) derived an equation to p r e d i c t annual erosion from C a l i f o r n i a watersheds, i n which erosion was related to the maximum yearly peak discharge, the area o f the main channel of the watershed,, and the cover density of the watershed.  In a l a t e r study  9  he  reported a more comprehensive equation which included as independent variables  9  information on the slope o f the channels, the s o i l s  9  roads  9  land-use pattern, and the character o f the hydrograph (Anderson 1960  9  1965)o The estimating of sediment production on the basis of s o i l s , topography  s  and f o r e s t cover i s a form o f erosion hazard r a t i n g .  The  equations constructed by Anderson (194-9» I960, I965) estimated the volume of sediment from watersheds given the values of the above variables.  A proposed change i n land management, e g o 0  9  c l e a r cutting  part of the watershed or building roads, could be used i n the equation to p r e d i c t the sediment production l i k e l y to r e s u l t ; i n r e a l i t y , an erosion hazard rating. Bullard (1962) c a r r i e d out a study to estimate sediment product i o n on the Umpqua River basin i n Oregon. standards, one given a  Two watersheds were chosen as  very high r a t i n g with regard to erosion and  70  sediment production, the other given a low rating.  Other watersheds were  rated by comparison to these standards according to observations on channel, slope, and road conditions checked against available sediment sampling data.  Geologic maps and aerial photos were used to extend the  rating to areas not visited. The author stated that though the sediment production ratings were guided to some extent by sediment sampling data, good correlation did not exist between them.  The total sediment of a l l the rated water-  sheds was calculated on a. per square mile basis.  However, as sediment  sampling data did not exist for the whole basin, a comparison of actual and calculated sediment production could not be made. The author concluded that the calculated production should not be considered as within less than - 30 per cento  The rating method was highly subjective and.  does not seem capable of producing figures on sediment production i n which confidence could be justified. Regression theory states that predicted values will be more precise when derived from independent variables than when derived directly from correlated variables.  Because of this, estimates of erosion hazard  ba,sed on independent variables are more precise than those based on related variables such as soil topography, climate, and vegetation, according to Alvis (1961).  He presented a theory to attempt "to reduce  soil erosion into i t s fundamental forces" (p. 3 2 ) , stability capacity of soil and moving capacity of an external agent.  The f i r s t expresses the  capacity of the soil to resist movement, i t s components being cohesion  71  o f t h e i n d i v i d u a l s o i l aggregates, f r i c t i o n between the surface aggre-  gates and t h e mass o f t h e average s u r f a c e aggregate,,  The second concerns  s  the erosive agent, and i t s components a r e mass and velocity,: Stability capacity and moving capacity are independent o f each othor and. their relation to e r o s i o n i s fixed.,  A l v i s s t a t e d that this  method, of rating erosion hazard has advantages i n a d d i t i o n t o i t s being based on regression theoryc  I f each of the two parts i s reduced to i t s  components, f a c t o r s affecting erosion c o u l d then be related t o the individual components on a rational rather than empirical basis:  An  example o f the type o f equation d e r i v e d from t h i s t h e o r y i s one for  water erosion hazard during the most intense probable rainfall period: Bea = 1/2  MV  2  = 1/2  (Mr x V r ) + 1/2 2  (>,p x V p ) 2  where Eea = the k i n e t i c energy o f the erosive agent  M V  Mr  mass = velocity  = peak r e s u l t a n t r u n o f f  mass  Vr  = peak resultant r u n o f f v e l o c i t y  Mp Vp  - peak r a i n f a l l mass = rainfall velocity  The a u t h o r concluded, t h a t e q u a t i o n s such as t h i s c o u l d be r e f i n e d as  kmwledge o f e r o s i o n grows, and t h a t a t any stage o f knowledge, hazard ratings based on the fundamental elements of erosion will theoretically be the most accurate, Ero si on ...Con trol As shown by many studies o f e r o s i o n and streamflow, a strong relationship e x i s t s between plant cover, streamflow, and soil stability,.  72 Control of vegetation i s a natural and usually very efficient way to maintain or restore s o i l stability.  In some cases, however, revegetation  i s not sufficient by i t s e l f to re-establish the hydrologic norm of a watershed but must be supplemented by engineering structures. The rehabilitation of damaged watersheds i s often an expensive job.  On forest areas i t w i l l require reforesting understocked areasj,  protecting against f i r e , and improving roads that are i n unsatisfactory condition.  Soil disturbance that has resulted in a concentration of  overland flow must be stabilized by vegetation, aided where necessary  9  by mechanical structures. In I960, wildfire burned over part of the San Dimas experimental forest.  Rice et a l . (1965)conducted studies on the areas burned to  obtain a quantitative evaluation of several mechanical and vegetative land treatments.  Watersheds seeded to low density perennials had higher  sediment production than did watersheds treated i n other ways. Planting annual grasses, the report stated, may be justified as an emergency erosion control measure because of i t s low cost and the speed with which i t can be applied. Of the mechanical treatments to reduce erosion, side-slope stabi l i z a t i o n and contour trenching were found to be superior to channel stabilization.  This supports the view that measures that prevent the  concentration of water are more effective than those aimed at reducing the erosive effect of channel flow.  j  In June, 1959» the Three Bar experimental watersheds i n Arizona were swept by f i r e .  Pase and Ingebo (1965) described the early results  73 on  sediment  and  water  yields  sweet-clover.  The  shrub  chaparral,  cover  birch-leaf area the  was  of  mountain  sprayed  resprouting  area  so  that  f i r e .  rates  by  Runoff the  has  been  the  control.  In effect  treatment study  the  after  i n  was  consisted that  settle  cover  out.  applied  the  stand  for  from  but  than  areas to  watershed  both  have  from  at  the  untreated  bank  rock  suocess  riprap  or  other  measures  outlined velocity  Contour  by of  year to  seeded  years,  after  pre-fire watershed  compared  increased about  to  greatly pre-fire from  the  streambanks  ( S t r i f f l e r  and  I960).  40  per  appeared  to  be  supplement  Bailey  and  Copeland  to  (1961).  vegeta-  Debris  flow  allowing  debris  and  retains  rainfall  on  land  the  and  stabilization  means.  used  The  cent  mechanical be  and  Bank  f e r t i l i z a t i o n . by  may  terracing  the  stabilize  which  channel  shrub  watershed.  erosion  to  f i r s t  however,  reduced  destroy  grass.  present,  treatment  seeded  to  the  to  areas  key  The  declined  to  and  I960, to  and  natural  Greene),  decreased  three  seeded  treated  the  Nutt.).  the  watersheds  seeding,  The  i n  from  last  since  greater  were  113  the  to  only  of  had  Runoff  riprap,  mechanical  the  was  watersheds  year.  grasses  beginning i n  rock  by  are  years,  both  f i r e ,  waterlines.  measures  betuloides  from  control  return  to  turbinella  to  yields  of  (Quercus  Spray  increased  compared  to  done  fourth  115  helicopter  allowed  (Cerocarpus  production i s  Michigan,  basins reduce to  the  natural  waterline The  tive  the  by  was  the  Sediment  showed  stabilized of  of  Sediment  watershed  the  end  oak  shrubs.  highest from  was  successive  damage  significantly  immediately levels.  natural  was  l i v e  four  seeding  area  mahogany  for  l i t t l e  Runoff the  control  of  sediment where  74 i t f a l l s , thus preventing overland flow and erosion, and creates favorable moisture conditions for the re-establishment of vegetation*  Small  check dams are sometimes constructed across the trenches, A modification of contour terracing i s pitting the soil surface with short, V-shaped trenches, at regular intervals.  Seeding with grasses or  legumes must follow pitting or terracing, otherwise the trenches would soon f i l l with sediment and lose their valueo In disturbed stream channels, check dams or precast cribbing are often used to control channel flow.  Sections of interlocking cribbing  are placed across the channels and because of their open structure permit water flow but retain sediment.  Design and construction of prefabricated  concrete were described by Heede (1965) and of rock check dams by the same author (1966), Bailey and Copeland (1961) discussed vegetation and engineering structures i n erosion control and concluded that three kinds of action were needed:  ( l ) wider public understanding of the importance of for-  ested watersheds, (2) a speeded up and more vigorous application of known and tested measures of watershed protection and rehabilitation^, and (3) more basic and applied research to f i l l the gaps i n our knowledge, 6,  WATER QUALITY  Eschner and Larmoyeux (I963) defined water quality as the sum of the measurable characteristics of the water. By this definition any change i n the character of water which i s not measurable does not affect  75  the  quality*  color, i n  The  characteristics  turbidity,  other  temperature,  pH,  characteristics  develop,  example,  techniques  be  That  the  and  i s ,  standards  techniques  i t s  a  usefulness of use  as  result  the  fishery  for  i t ,  of  Bullard  i s  the a  sum o f  i t ,  w i l l  Its  w i l l and  be  water  the  are  to  of  new  measure  quality  usually  measured  conductance.  is  accepted  a  uses  for  these  As  the  are  interest  water  for  characteristics.  measured  as  quality  (Bullard reduced i t ,  i n  the  defining  the  next  quality sum o f water  for  of  change  the  water  1963)*  as  purpose that  uses  some  the  industries  f i l l  up  on  fish.  effeot  of  describe  Consider  because  reservoirs  detrimental  define  However,  i s  drink  has  water  characteristics  value  discussed to  of  purpose  not  i t  attempted  possesses*  generally  which  that  specific  because  developed  specific  people  aspeot  water  and  definition  muddy w a t e r .  cannot  the  better  discussion i s  example  by  water  develop.  Perhaps this  w i l l  of  with  sediment  (The  section)*  as the  the  degree  of  measurable  quality,  and i s  excellence  characteristics the  more  useful  definition* The by (1)  four The  influence  of  the  forest  on water  quality  can  be  summarized  statements: amount  of  sediment  in  streamflow  taste  water  is  affected  by  forest  cover, (2)  The  color  stream (3)  Water  and  of  i s  affected  by  logging  debris  channels, temperature  i s  affected  by  the  removal  of  trees  along  i n  76  streambanks and by forest-cover changes that a l t e r the proportion of water that reaches stream channels by surface flow, (4) Timing o f runoff i s affected by forest-cover changes.  Timing  i s included i n water q u a l i t y by the second d e f i n i t i o n given above. Changes i n water temperatures brought about by logging are not l i k e l y to a f f e c t the q u a l i t y of water f o r human use but are important i n f i s h e r i e s , and w i l l be discussed i n the section on forests and f i s h . Timing has been discussed i n the section on streamflow and w i l l be considered further i n the section on forests and f i s h . The influence o f vegetation on erosion was discussed i n the previous section.  Conversion o f forests to other land uses generally  favors f a s t e r erosion rates, higher sediment loads i n streams, and impairment o f water q u a l i t y . The t u r b i d i t y o f water i s i t s capacity f o r absorbing or s c a t t e r ing l i g h t and i s measured by the concentration o f f i n e s i l i c a which produces an equivalent e f f e c t (Camp 1963) < > Another method o f determining t u r b i d i t y i s the Jackson candle method by which the depth o f water through which the flame of a candle disappears i s converted to an index number.  For example, i f the flame disappears when viewed through 72.9  cm. o f the sampled water, the t u r b i d i t y i s 25; through 10.8 cm. the t u r b i d i t y i s 200.  These units were o r i g i n a l l y intended to be equivalent  to p.p.m. (parts per m i l l i o n ) of standard s i l i c a suspensions, and therefore t u r b i d i t i e s are often expressed i n p.p.m. the same as t u r b i d i t y units (Nordell  1961).  Numerically these are  77 Turbidity may result from l i v i n g or dead algae or other organisms, but i t i s generally caused by s i l t or clay,  Th6 amount and character of  turbidity depend on the type of soil over which the water has run and the velocity of the water (Steel I960),  AS the velocity decreases, the  heavier particles settle out, but the finest clay particles may require months to settle out of s t i l l water. For drinking water, the United States Public Health Service standards are widely used.  These specify that the turbidity shall not  exceed 10 units for culinary and drinking purposes (Nordell 1961), Turbidity tolerances for industrial purposes run from as low as two for carbonated beverages to 50 for paper produced from groundwood pulp, A turbidity of 20 00Q or more can be tolerated for fish propagation. 9  The  effect i s an indirect one i n that turbidity reduces light penetration and this limits photosynthesis and algal growth, the lower links i n the food chain on which the fish depend (Camp 1963)° Soms rivers have turbidities as high as 60,000, and extremes of over 100,000 have been measured (Nordell 1961), Effect of Logging on Water Quality Loggings  Logging greatly affects water quality not so much be-  cause of the conversion of forested areas but because of the methods employed.  The use of heavy machinery i n areas formerly inaccessible  because of steep slopes and rugged terrain disturbs soms of the soil surface to varying depths and degree. sediment discharge.  The result i s greatly increased  Studies i n Oregon have shown that 10 years of  78  logging than  one watershed  an unlogged  Sierra the  i n  Nevada  for  areas  watershed  that  logged with p e r cent  two y e a r s  o f mineral  o f  logged  areas  22  p e r cent  o f  tractor  (Fowells  and Schubert  the area  Washington.  Mineral  logged  by t r a c t o r  Garrison  15.2  o f logging  5  was b a r e  by tractor s o i l  and only  o f areas  horses.  after  Wooldridge  5»k  per cent  o f  (1951),  1962).  i n  eastern  with  logging  by  o f  Crane the  logged  pine  crawler  reported  Skyline  o f  cables,  the California  the area  times  per cent  20.9  per cent  the  considerably  (i960)  a n d by t h e Wyssen  was e x p o s e d o n 22.2  and Wallis  logged  In  In  1965)0  vary  averaged  ground  1951).  (Rice  erosion  discharge  l o g g i n g w a s 17  and Rummell  per cent with  after  times  soil  sediment  and Wallis  one year  after,  tractor,  greater  (Anderson  and the r e s u l t i n g  exposure  comparison  p e r cent  discharge  l o g g i n g methods.  found  a n d 11.8 zone  rate;  disturbance  different  Oregon,  adjacent  the sediment  pre-logging Soil  p r o d u c e d 80  a i n  area  by  Skyline  Crane. Dyrness H.J.  Andrews  high-lead  (I965)  reported  Experimental  and tractor  conditions.  Surface  Forest  logging area  a  study  i n Oregon  on s o i l s  o f four  o f disturbance:  undisturbed,  turbed,  and compacted.  The t r a c t o r  per  area cent  amount  i n  within against  the compacted nine  class  per cent),  the undisturbed  class.  was c a r r i e d  to  with  d e a r c u t  degrees  more  which  similar units  slightly logged than  and a  assess  the effects undisturbed  was c l a s s i f i e d  disturbed,  area  out i n the  had about  d i d the high  deeply three  lead  area  corresponding decrease  Deeply  disturbed  o f surface by  four  d i s times (27  i n the  and compacted  classes  79 had higher bulk densities, i,e,, decreased soil porosity.  The author con-  cluded that tractor use results i n increased runoff and erosion., but this i s minimized i f slopes do not exceed 20-30 per cent, A study i n Russia showed that after a shower of 63 mm,  (2,5 in,),  lasting two days, erosion was 5° 3 kg,/ha, (4,7 lbso/acre) i n forest stands of 60-70 per cent density, 15<>1 kg,/ha, (13»5 lbs,/acre) i n stands of 20-30 per cent density, and 32°1 kg,/ha, (28,7 lbs,/acre) i n cut-over area (Molchanov 1963), In the northern Caucasus and i n the Urals, hauling with horses caused s o i l erosion of 200 cu,m,/ha, (106 cu, yd,/acre) on slopes of 10° or less, but as much as 550 cu m,/ha, (291 cu yd,/acre) on 0  0  slopes of 10  0  0  .  - 20 5 and with tractors the values were 550 cu,m,/ha,  (291 cu, yd,/acre) and 780 cu, m,/ha, (413 cu, yd,/acre) (Molchanov 1963)o The cutting of timber i n i t s e l f does not seem to affect water quality  9  although there i s some evidence that increased streamflow re-  sulting from timber cutting may cause stream-bank erosion and thus increase sediment production (Packer 1965)0  Log skidding, particularly  where equipment i s used that deeply disturbs the s o i l mantle, often increases sediment production, however.  The degree of increase depends  on many factors such as the location of skidways i n relation to stream courses, the adequacy of drainage f a c i l i t i e s , the size of storms, and the nature of the terrain and s o i l . Logging, even when carried out on steep terrain  8  does not nec~  essarily reduce water quality as was shown by experiments carried  80 out on the Fernow Experimental Forest i n the mountains of West Virginia (Hornbeck and Reinhart 1964)o  I t was pointed out i n these studies that  most of the damage to water quality occurs during and immediately after logging.  Where skidways become revegetated slowlyhowever  9  impairment  of water quality can continue for many years. Stream channels.  Logging debris i n stream channels can discolour  water and cause a disagreeable taste.  This i s relatively unimportant  where the proportion of the watershed that has been logged i s small and 9  where the dilution effect of large reservoirs occurs.  Where the opposite  i s the case usually confined to small communities where the water supply 9  i s taken directly from the stream, the quality of water for drinking purposes i s definitely impaired. The hazard associated with debris i n stream channels i s the log jam that sometimes occurs during runoff. During high water the jams often break up sending a mass of logsj, rocks mud and water downstream 9  s  causing damage to property and changing channel alignment. The question arises as to the size of stream from which i t i s necessary to remove logging debris.  Rothacher (1959) pointed out that  to answer the question information i s needed on maximum flow from the stream and the size of stream that can move logs.  He suggested that  any stream fed by a watershed greater than 40 acres should have logging debris removed. Roads.  Road-building associated with logging i s largely respon-  sible for the increased sediment discharge of logged areas.  Modem equip=  ment has made road building easy enough that often roads are built piece-meal  I  81  without an overall plan.  This may result i n more miles of road than other-  wise needed, and often the location i s poor, Silen and Gratkowski (1953) reported that 12,4 per cent of the total area logged i n a study conducted i n Oregon was disturbed by road building and landing construetiono  Building of 1,65 miles of logging  road on one of the watersheds of the H J 0  0  Andrews Experimental Forest  in Oregon caused sediment discharge from the f i r s t rainstorms after construction 250 times that of an adjacent undisturbed watershed. Discharge during the following two years was about twice that before road construction (Frederickson 1965), The reasons for increased sediment after road building include; (l) roads often intercept seepage and concentrate the flow  9  and (2) road  surfaces often have lower i n f i l t r a t i o n rates due to the disturbance and compaction of the s o i l , A logging system requiring fewer miles of road would be expected to contribute a smaller amount to stream sediment. In the comparison of tractor and Skyline Crane logging i t was shown that the truck road , system needed for logging by Crane was about 10 per cent of that needed by standard methods (Wooldridge I960),  In the same study i t was reported  that transporting logs across a stream channel caused l i t t l e disturbance with Skyline Crane but even well-planned crossings produced s i l t and • debris during runoff periods after tractor logging. Eight l/lOO ac, plots were set up on the f i l l slope of a newlyconstructed highway i n Idaho to determine the effect of various treatments on erosion from side slopes (Bethlahmy and Kidd 1966), Those  82  plots that were seeded and f e r t i l i z e d produced the greatest amount of erosiong, an average of 97 lbs, during the 322 days i n which the research was i n progress.  This figure i s larger by 13 lbso than that for the  control plot on which no control measures were taken<>  The addition of  straw mulch to the seeded and f e r t i l i z e d plots was responsible for a reduction of erosion to 24 lbso  Seeding, f e r t i l i z i n g , straw mulching,  and netting reduced erosion to 0 5 lbs. o  In many parts of North America, especially i n mountainous regions, secondary roads are "put-to-bed" after harvesting of timber has been completedo  This usually involves removing temporary culverts, out-  sloping the road surface, installing earthen cross drains at prescribed intervals  y  and perhaps seeding the road surface and cut bankso  In resent years, the outsloping of road surfaces and removal of berms or curbs have been questioned, especially on "incurved " sections 1  of road i n steep terrain.  In such locations surplus road material i s  usually caste ver and comes to rest i n long unstable f i l l s extending for 100 f t , or more down the ravine.  Such f i l l s are usually shorter on side  slopes below "outcurved" sections of road. In a study carried out on a newly-built, secondary logging road i n Idaho, both concepts were evaluated (Haupt et a l , 1963)0  Observa-  tions indicated that insloping the road surface was more desirable than outsloping as an erosion-control measure.  The inslope should be designed  83  to  lead  of  the  away  per  much w a t e r  as  possible  from  the  long  a  clearcut  watershed  f i l l  on  the  incurve  road. In  roads  as  West V i r g i n i a ,  and  no  provision  million).  skidroads  for  Partial  resulted  in  on  drainage,  cutting  of  turbidity  an  of  turbidity adjacent  only  was  unplanned  skid  56.000 p . p . m .  watershed  p.p.m.  25  with  with  (Reinhart  (parts  well et  planned  al.  1963). study  A dicated and  that  Kidd  area  bared  the  which  by  roads The  roads  streams  sediment  streams  the  stream.  road  i n  were  travelled  from  but  of  to  the  the  road the  and  for  sediment  occasionally  be  2( s l o p e  per  cent)  be  4(slope  per  cent)  primarily to  30  relating  +50.  ft.  wide,  affected  the  the  logging  sediment  related  width  and n o t the  distance to  where  stream:  municipal  slope. i t the  i s  that  total  skidroads, with  roads  did  reach  not  between  stream  sediment  They  devised  accepted  watersheds  to  between  strip  width  (Haupt  frequency  strips  of  i n -  Sedimentation  sedimentation  the  this  situation  For  roads  Where b u f f e r  ft.  not  of  to  disturbance.  stream  studied  reach  of  was  on haul  measuring  general  + 25  the  stream.  by  contributors  severity  (1957)  Hampshire  major  sedimentation  sedimentation  the  than  rule-of-thumb w i l l  of  that  Sartz  relating  the  road  greater  and  New  were  amount  reached  Trimble  Idaho  originated  proximity  and  and  central  haul  1965).  reaching and  i n  of  that  strip  the  a some  should  strip  should  84  A the  study  four  function  sediment  plant  cover),  width  of  occur  from  protective a  were  slope  and  from  road  the  cross-ditch f t . ,  tective  given strip,  optimum  structures nates was  reach  for  and  length,  to  obstruction and  and  road  was  developed  would  estimate  sediment  the  roads  prediction line  from  the  This  streams  channel,  having  movement  the  that  so  (2)  the  (3)  embankment  slope  length,  and  spacing  of  water  controlled The  on  disposal results  skidtrails spacing  bars  of  depends  of  located control on  the  the  road,  skid trails  may  maximum  length,  30  a  ft. of  and  narrower  than  width  pro-  of  of  slope given  to  most  water  than  from  those  structures,  such  as  and l o c a t i o n  of  effective  that  ravines  log  strip.  determine  that  slope  i n  permissible  indicated  i n  study  given  protective  the  The  flowing  apart,  study  (1)  useful  sediment  sediment-laden his  prove  strips  width  conducted  of  proposed  minimum number  spaced  Idaho,  giving:  that  slope  ditches  i n  equation  should  protective  embankment  gradient,  of  cross  ditching,  slope  variables,  below  from  slope  obstructions,  equation  dissipate  aspect.  the  exposure,  road  skidtrails.  cross  regression  centre  away  working  Optimum  slope  embankment  to  from  the  (1963),  for  greater  h i l l s . and  on  and  to  not  slope  distance,  distance  road.  enough  needed  gradient, Kidd  the  does  sediment-flow  characteristics:  dependent  needed  gradient  interval  obstructions road  far  flow  the  developed  slope  roads  for  relating  downslope  A multiple  distance  side  Idaho  interval,  strip  proposed  locating  200  1959)*  substitution  Guides  road  of  and  cross-ditch  (Haupt  with  minimum  in  road  (a  which,  conducted  significant  index  gradient  was  o r i g i -  erosion on  water  the  sidebars  skidtrail  85  as  well  the  as  s o i l  skidtrail  only  retard  onto  water  besides be  conducted  to i n  situation. erosion  ing  a l l  that  forest  floors  f i l t e r  out  a  each  area  control  insloped though  of  particular  However,  i t  by  surfaces, be  different  erosion  control.  should  be  studies  the  study  warrants  assumed  be  along  and  The  the  be  Haupt  et  those  the  His  to  water  variables  warning of  apply  can  studies i n  every  and methods  applied  road  applies  of  where  (1963).  a l .  i n  that  s k i d t r a i l .  many  results  should  method  to  o f f  protect  that  assumed  consideration  that  to  considered  by  water  superior  discharge.  cannot  those  example,  cannot  are  divert  sediment  sediment  studies  suggested  road  i s  location  such  For  that  p r e s c r i b i n g l o g g i n g methods  aspects  applicable.  even  i n  and  Structures  l o g g i n g method i n f l u e n c e  applied  seem  movement  cautioned  f  material.  undisturbed  (1963)»  Wallis quality  parent  they concern-  construction  i n  a l l  s i t u -  ations. Actual aspects  of  prescriptions  logging,  s h e d management Fire. to The be  which i n  (For  a  fires  Ahlgren  covered  often  these  this  sidered. see  i s  burned or  building, i n  Chapter  to  after  make  objectives  section,  comprehensive and  road  as V  well  as  which  for  deals  other with  water-  Columbia.  regeneration,  to  discussed  be  British  Slash  facilitate degree  i n  w i l l  for  Ahlgren  but  the  are  the  area  to  reduce  amenable  met  by  slash  effect  on  erosion  discussion  i960,  logging  Davis  of  the  1959»  to  f i r e  hazard,  planting.  burning w i l l  effects  will of  and J a b l a n c z y  be  not  con-  forest  1963)»  86 Evidence s o i l  was  reported  by  (1956) a n d  Scott  i n  the  of  to  be  may  time  be  the  top  reduced  by  reported matter  of  the  by  burned eight  cent  after  pointed burned  severe area.  after  per  was  cent  out,  of  a  be  that  whereas  burned.  that  far  that  i n  the  l i g h t  the  and  soils  the  this  what the under  surface  moisture-holding  affected Dyrness  i t  was  less  area  by et  due  to  excess  Croft  (1946) r e p o r t e d  that  fires  and  on  of  on  extreme  only  than et.  2  to  five  a l .  fuels  capacity  the  f i r e  a l .  (1957)  less  was  organic  10  per  the  rates.  cent  of  In the  (1957) r e p o r t e d  of  Bethlahmy  these  insignificant floods  percolation  per  burned.  erosion  their  reduced  increased  severely  effect  may  burns  burns  Dyrness  areas  overgrazing  severe  study  slash-burned  however,  that  burning.  concluded  Tarrant's  severely  for  influencing  of  soils  was  burning.  cent  examined i n  the  significantly  slash  (1956) r e p o r t e d 70  of  rate  Differences  responsible  characteristics  the  attributed  surface.  variables  of  I963).  s o i l  and  i n f i l t r a t i o n  s o i l  largely  (1955) r e p o r t e d  33»7  s o i l  the  Other  content  (Dyrness  of  the  i n  i n  capacity  (1952) w h o  Scott  probably  the  moisture  inch  area per  i n  i n f i l t r a t i o n  increase  and  evidence.  evidenoe  the  aggregates are  Baisinger  per  An  Burgy  one-half  over  areas  the  and  Tarrant rates  burn  burning  similar  in  the  differences  and  Austin of  of  conflicting  investigation the  Rowe  larger-sized  severity  evidence  (1941).  by  formation  appears  burning decreases  reported  to  at  that  i n  Utah  cent  of  only  (I960)  severely area! were the  extent. traced  to  headwater  87 Most effect  on  of  the  water  evidence  movement  been  burned,  however,  with  time  the  by  rain  as  drops  creased  peak  pine  Workman  on  surface  runoff  looseness  of  Creek,  s o i l  expected  by  and  1953)*  Accelerated  and  erosion  Connaughton  (1935)» H e n d r i c k s The  then,  affects  f i r e s ,  derived i n and to the  by  British  value  increased  man  water  trout  returning  ocean.  After  the  well  Columbia  steelhead sea,  as  of  to  If  be  (19&5)  *  s o i l The  o  the  r  i s  l i t t l e  l i t t e r  expected  mineral  to  has  decrease  broken  result  down  may  wildfire  a  are  sediment  FORESTS  salmon  spawn  emergence  (1955)»  and  i n  be  i n -  ponderosa  must  Board  stream  from  the  to  greater  due  to  the  (Dyrness and  been  (1944),  and  to  an  matter  1957» by  Youngberg  many  (1953)»  resulting  extreme  i n -  (1949)»  Trobitz  Pillsbury  supplies  and  organic  reported  Anderson  often  and  from  degree.  FISH  include benefits  (sockeye,  clay  due  and Youngberg  water  AND  economic  River i n  i n  and  1940)  burning has  quality,  (Fraser  Dyrness  f i r e  rates  decreased  and Johnson  the  after  Aurangabadkar  fisheries as  by  Anderson  7,  The  can  i n f i l t r a t i o n  after  a m o n g whom a r e  (1953)*  p r o f i l e .  increase  1955»  Balsinger  vestigators  Sartz  burning has  sediment.  Rich  caused  Y o u n g b e r g 19 5? > S r e e n i v a s a n (Austin  the  by  to  reduced  particles  content  l i g h t  Arizona.  be  caused  by  soil  of  clogged  reported  that  capacity  structure  pores  as  would  the  i n f i l t r a t i o n  the  flows  Erosion  through  surface  and  indicates  pink,  1958)•  gravels gravel  the and  costs.  coho,  fry  benefit  Important  spring,  These  after as  recreational  and  migrate  one  or  the  fish  chum)  from  more y e a r s spend  stream in  88 different lengths of time i n fresh water depending on the species  so that  s  the freshwater environment has greater importance for some species  0  Water Yield and Regime Discussion of the forest and f i s h mainly concerns the influence of logging on the yield, regime and water quality of streamflow, a  The  effect of logging on water yield was discussed i n the section on streamflow,,  Most studies have shown that clear cutting increases yields by  four to eight inches, but the effect on regime i s not as well defined , (Jeffrey I965). Some studies indicate that cutting causes greater low flows (Eschner and Larmoyeux 1963a Kittredge 1948, Meginnis 1959s Rothaeher 1 9 6 3 % and Shirai et alo 1954)*  This may be explained by precipitation  being well distributed through the year so that low flows are probably due not to a lack of precipitation but to high evapotranspiratlon.drain (Esehner and Larmoyeux 1 9 6 3 ) 0  Greater minimum flows, where low flows  are critical,, would improve the survival of f i s h during this period and favor higher f i s h populations  0  Greater flows i n summer would provide  greater water surface for catching terrestrial insects, greater algae and insect-producing bottom area, and more room for the fish (Chapman 1963)o The results of some studies indicate that removal of the forest causes higher peak flows (Bates and Henry 1928, Hirata I 9 2 9 Troxell 1934, and Tennessee Valley Authority 1962)0  2  Hoyt and  Higher flows may  89 result and  i n  channel  higher  logging water  road  so  while  others,  and  other  Erosion  movement and  of  stream-bottom  sediment  discussed  that  add  lower  the  in  the  1963).  Gravel  insects,  young  fish  creases  as  to  (Peters oxygen  of  of  cover  gravel  i.e.,  their  sunlight  carry  velocity  of  loads  and  Fish velocity  may  food  discharge  sections  gravels,  caused  on  embryos  by-  erosion  and  1962).  water  metabolic  content  The even  decreasing  the  out  0  k i l l  future  i n  beds,  and  embryos  emerging  fish  may  from  embryos,  populations  and  which  small  l i v i n g  The of  gravels  for  of  g i l l  the  eggs,  fish  space,  of  fish  large  water  by  sediment.  to  reducing organic  maintain  oxygen  sediments  plants  oxygen  the  Sediments the  and  membranes  dissolved  the  f i s h .  green  need  reduce  hide,  of  products.  thus  fish  growth  the  sufficient  waste  water  in  death.  decomposition of more  stream  incubating  fauna  inflammation  spawning  intra-gravel  movement may  interstices  filtered  in  on  the  high mortality  stream-bottom  eventual i s  deposition  by  spawning  supplies.  cause  intra-gravel away  thus  established  transported  suffer  decrease  may  remove  debris  fry  depth,  sediment  the  hatched  aquatic  number  to  can  the  reducing present  and  cutting  Gravel  (Chapman  and  and  locations.  Sediment  and  cutting,  b u i l d i n g was  scour  deep  algae,  High  loads.  Channel  gravel  size  and  quality.  dumped i n  the  sediment  and  isolate  be  scour  de-  and  oxygen  reduce  of  a  supply  the  available decreases  the  90 Debris  i n  Channels  Logging section or  the  on  stream  result  barriers  to  When l o g  jams  often  i n  of  the  but the  previous  dissolved  oxygen  organic  can  debris,  results also  water  alignment.  The  stream  by  i t s  the  i t  debris  be  debris  the  channels  often  resident rushing  of  main  normal  These  for  effects  matter  discussed i n  jams.  pools  and  Probably  in  l o g  provide  up  was  whether  i n  section.  caused  water  distribution to  and  F.  83°  and Larmoyeux condition  of  this  i s  the  as  f i s h .  downstream  action  hazard  act  to  are  d i s -  f i s h  reduction  of  decomposition.  temperatures survival  for  brook,  (19^3) the  d e a r  but  cutting  on  the  by  loss  of  could  species,  3°5°  vegetation  (Chapman  unfavorable  F.  often  Limiting  and  rainbow  vary  the  by  also  1962).  extend  Fernow 8°  (Eschner  may  Lower  insulation  thus  are  with  high  trout  the  pH,  the  factor  l i m i t i n g  temperatures are  cited  by  of  from  Eschner  dissolved oxygen,  and  fish.  temperatures  atures  summer  trout.  these  temperatures  riparian  of  i n  brown,  summer w a t e r  This  Such  channels  Temperatures High  the  stream  stored  channel  from  75°  channels.  break,  the  i n  logging, often  resulting  Water  l e f t  migration  change  cussed  debris  conditions.  by  for  Removal  maximum water  of  maximum summer w a t e r  streamside  of  increased  1963).  temperature  period  period  Forest  d e c r e a s e d minimum w i n t e r  increased  winter  incubation the  and  and Larmoyeux  cause  provided  increasing  F.  Experimental  m i n i m a may  vegetation  f a l l -  and  vulnerability  result  (Green  temperfrom  1950)°  winter-spawning of  embryos  to  91 (I963)  Chapman summer  temperatures  metabolism. might warm  be  Where  suggested  causing streams  advantageous,  streams  would  l i k e l y  p o s s i b i l i t y  accelerated are  but  the  cold  the  an i n c r e a s e prove  algal  the  detrimental  increased  production  effect i n  of  of  and  increased  temperature  in  net  and  f i s h temperature  of  effect  spring  already  (Jeffrey  1965 ). Removal of  aquatic  to  reduce  Chapman coho the  of  riparian  insects the  provided  number o f  (1963)  insects.  The  diet  i s  tion  removal  reaching  that  with  Thirty  other  per  should stream.  70  plant  also  per  per  cent  i s  materlalo algal  of  plants. of  the  the  It  reaching  cent  aquatic On  down o n  plants.  insects  60  over  cent  stimulate  cuts  terrestrial  terrestrial  manner.  terrestrial  the  by  terrestrial  estimated  salmon o r i g i n a t e d following  vegetation  other  p r o d u c t i o n by  i s  hand,  tend  surface.  reaching  estimated  diet 50  supply  also  water  energy  This  insects,  food  would  the  the  cohos'  the  per  i s  terrestrial  cent  however,  increasing  i n  the  of  whose  vegetal i g h t  92  CHAPTER I I I .  ADMINISTRATION OF WATER RESOURCES 1.  JURISDICTION  B r i t i s h North America Act An a c t f o r the union o f Canada. Nova Scotia, and New Brunswick, and the government thereof; and f o r purposes connected therewith; otherwise known as the B r i t i s h North America Act, 186?, i s often blamed f o r many o f the problems i n v o l v i n g the federal and p r o v i n c i a l governments  (Information  about the B.N.A. act i s from S i r o i s 1940). With s p e c i f i c regard to the water resource, "the B r i t i s h North America Act i s the root of today's dilemma" (C.A.A.E. 1966, p. 10).  This  statement brings f o r t h the following questions: (1)  Are there j u r i s d i c t i o n a l problems with the water resource?  (2)  I f so, how do they manifest themselves?  (3)  Is the B.N.A. a c t responsible?  (4)  What solutions can be proposed? Relevant sections of the act.  The sections o f the B.N.A. a c t relevant  to the water resource are Sections 91» 92, and 95«  Section 91 l i s t s the  classes of subject that are the exclusive l e g i s l a t i v e r e s p o n s i b i l i t y o f the parliament of Canada.  Provincial legislative responsibility i s l i s t e d  i n section 92, as well as section 95 which includes laws r e l a t e d to a g r i culture. Section 91 of the B.N.A. act includes navigation and shipping (para. 10), sea-coast and inland f i s h e r i e s (para. 12), and peace, order, and good  93 government regarding and  the  in  Canada.  the  management  timber  on  them  transportation  lines  country  10),  the  (para.  province  Section  (para.  the  result  of  The  resources  within  a  ever,  federal  and  the  fisheries  reservesp over  are  along  generally  16)  (Sirois  i n  general  considered  are  of  the  c o n c e r n e d j,  as  in  1962).  The  omission,  as  as  of  legislation  b e l o n g i n g to  the  undertakings  other  between  matters  powers,  the  province  a local  or  province than  and  private  another  nature  i n  the  water  B.N.A.  control,  as  water  international  resources  act  and  in  their  over in  of  the  water  boundary,  of  How-  navigation  parks  and,  has  water  province. where  national  Canada  subsequent  and development  responsibility  well  the  of  n  i n  Indian some  cases  $  waters.  even  (Lederman  or  and  jurisdiction  expression of  necessary  well  provisions  has  the  lands  works  administration  crossing  provincial  19^0).  parliament  terms  all  administration,  inter-provincial Obviously  is  The  as  public  local  5)»  and  province  or  of  connecting provinces  the  interpretation.  sale  (para.  Interpretation. been  and  includes  92  yet a  open  to  of  conflict  this  powers  of  to  allow  between  the  is  levels  O F WATER  two i n  levels  many  f l e x i b i l i t y  f l e x i b i l i t y  EVOLUTION  the  interpretation  federation  price  2.  the  cases.  to  sometimes  of  of  the  government This  was  constitution  duplication  and  government.  POLICY  Canada Evolution objectives l i g h t  by  as  the  forestry  of  water  need and  policy  became  in  Canada  apparent.  conservation  came  about  The needs  conferences  by  were  which  had  restatement often great  brought  of  policy  to  influence  on  94 water  policy  at  Early  topics  over  discussed the  federal  conferences.  presided  1906,  the  by  was  made  by  (1)  Forests  should  (2)  Greater  emphasis  fire,  conference  a  held  declaration  l a t e r  in  of  and  recommendations undertaken. the  United  was  States  of  governments forestry,  a  and  lands, The  i n  program.  domestic  water  During interest  in  a  in  to  on  and  Laurier.  water.  protection  up  were  deal  a  in  of  each In  Conference,  commission of  on  The  of  North  1909<>  held  Among  in  the  recommendations  the  forest  natural  multiple  of  the  May,  from  forestry  the  countries  from  water  included land  mainly  the  resource to  approved  main  and  use  of  after  federal  six  minerals  agencies  One  months  cabinet  commission had  dealt  on  came  be  those  in  represented.  three  Canadian  committee  conference  influence  of  Conservation  commission s i m i l a r  1909,  water,  this  resources.  use  representatives The  American  From  an i m p o r t a n t  with  the  wildlife,  The water  the  conservation  Commission.  and  attended  February,  study  set  committee  Wilfrid  was  ownership.  placed  which  that  fish  forests  crown  Canada  universities.  healtho their  be  was  Conservation  establishing  from  that  be  Sir  Convention  insects.  Canada  Another  Conservation American  under  Washington  in  of  Forestry  included:  principles  established  Canadian  Minister,  relation  should  Representatives  f i r s t  Prime  remain  disease,  Conference  The  the  the  level.  the  the  and  principle  provincial  committees:  fuel,  and  public  and watershed with  North  water  studies  power  and  supplies. the  period  natural  1909-1921  resource  topics  the and  Conservation provided  a  Commission public  forum  stimulated for  discussion.  95 The  commission  gradually  became  charter..  This  intended  by i t s  to  out research  carry  ing  by  the Conservation  The  coordinating  water  policy  i s  Natural Commission  194-3,  brought study  about  Conference.  s t i l l  not revived  and s o c i a l  committee  (1)  Develop  conservation  (2)  Carry  o u t surveys  (3)  Enact  a dominion  Carry The  advisory  the  federal  research and cial  to  of  o f  however,  which  agencies  not  s e t up  f o r  had been of  abolish-  carried  federal  and the effect  measures  out  agencies.  on  Canadian  o u t by the  the great  Conference  changes  Committee  i n  o f  194-5.  Canada's  In  economy  on Reconstruction  Among t h e  Reconstruction  to protect  Conservation  recommendations  Conference  renewable  to  were:  resources.  resources. act to divide  forestry  work  between  the  governments.  This  resources. adopted  l e d to  accepting  f o r the development  carried  the country.  a  i n large statement  as i t s  f o r the development  (e.g.,  a function  the reasons  the responsibility  the National  Conference  government  i n nature  of  o f water  committee.  essential  federal  the Reconstruction  aware  l i f e  forest  out studies  the  the work  s e t up t h e A d v i s o r y  and p r o v i n c i a l  National  of  on the scale  until  government,  by this  (4)  with  a n d was o n e o f  was n e g l e c t e d ,  studies  made  federal  research,  apparent.  by the war,  economic  friction  Much  Commission became  function  the federal  created  toward  1921.  resource  were  oriented  responsibilities  the commission i n Reconstruction  more  of  the recommendations  o f policy  responsibility and management  and conservation  the protection  part  o f  resources  regional  on the part  the basic o f natural that  are  watersheds).  o f  o f  surveys  and  resources  interprovinThe  federal  96 government resource  would  provide  development  Resources conferences The  Prime  I958, ing  a  met  during  i n  the  Examination  (3)  Clarification  the  to  alleviate  change  Canadian Canadian  Council  allow  the  times  a year  agency  of  on  but  of  establish  are the  to  the  were  on  G.  most  for  ambitious  Tomorrow  Diefenbaker,  conservation to  years  plan  for  e n d i n g up  problems  being  done  impediments achieving  was  provinces  the  of  for  Conference  be  the  of  1961.  February,  called.  conference  with  resource  announced i n  would  requiring  to to  solve  The  whose  steer-  objectives  following.  attention  these  further  solutions  set  of  were  out.  The  management Resource  Resource ministers  a  examined  resource  resource  discuss  provides  governments  The  Resources  John  major  is  the  Council  resource to  to  in  the  f i e l d .  resource  these  views  Hon.  three the  agreement,  to  problems.  progress these  and  problems  1962).  management  of  of  the  same y e a r  what  courses  water  i n  of  of  (Kristjanson The  the  specific  Conference.  conference  resources  (2)  possible  Rt.  next  Identification renewable  to  the  national  committee  (1)  Tomorrow C a n a d a was  Minister,  that  evolved  i n  by  1962).  (Thorpe  for  held  assistance,  necessary  isolated  was  Ministers.  senior  11  and  policy. which  coordinated.  this  conference.  recommendations  agreed  that  a  this  need  Problems designed  regular  ex-  necessary.  of  the  at  conference  was  resource  and  detail  Ministers  forum within  examined  in  To m e e t  formed i n  governments  The the  February,  council resource  The  11  coordinating machinery  i s  to not  governments to  allow  to  1962,  meet an  policies  the  several  executive of  member  agreed  also  cooperation  between  97 the  various  departments  The  f i r s t  shared-cost guidelines  project  resource drawn  up  Concerning  sponsored  the i n  ments. water  for  national  and  use  i n  resources  the  was  object  the and  Conference  Canada's  1966).  was  a  study  believed  (Can.  Coun.  Res.  "Pollution  I966.  The  agencies  i n  federal-provincial  69  examined  and  a  set  of  agreements. that  of  of  were  resource  understanding  instrumental  of  to  the  use  i n  a  serious  present and  aim o f  our this  establishing  of  optimum use people"  the  the of  and  policy water  and  best  1965°  as  by  waters  p r o g r a m was  development  described  of  Premiers'  July,  having the  study  of  management.  conference  council  held  was  coordinated  this  The  Environment",  to  i n assist  programs  is  "to  a  for  improve  The that  out  at  the  are  endeavoring  Premiers"  a l l  of  Conf.  our  The  statement, there  to  their  the  study  rational  a b i l i t y  to  federal  man-  government's  acknowledging regional foster  Canada 1965,  of  evaluate  Federal-Provincial  "to  govern-  1965a, p«3)»  (IHD  Conference.  Inter-  and p r o v i n c i a l  accelerate  view  advantage"  set  UNESCO-sponsored  federal  with  to  throughout  (Federal-Prov.  the  1965-1974,  mankind; to  in  backed  decade,  regimen  them  water  Ottawa,  (IHD)  this  interest  Canada's  endowment, and  future  council  an  Decade  and  gradually-evolved  ment  management  Deficiencies  conference  Federal-Provincial  to  in  industrial  Hydrologic  resources  v i t a l  council  agreements.  f i r s t ,  council  The  agement  resource  control.  The national  the  October-November,  governmental pollution  of  water,  required,  Montreal  in  1965).  Ministers  resource  involved  as  and  that  Premiers water  i s  differences  in  both  manage-  on  quoted  a  wise  behalf by  of  water  a l l  C.A.A.E.  98 At  the  government's and  applied  control for  Federal-Provincial water  research,  measures),  irrigation),  publication  British  of  development  consultation  Manitoba  having  to  had  established  been  mainland  entering  British  Water but the  British  denial The  act  policy  form  the  1965»  of  consisting  protective  of  projects  the  federal  inventory,  regulations  provinces  technical  by  of  i n  the a  (e.g.,  (e.g., water  basic pollution  diversion  and  the  United  States,  of  the  Dominion o f  in  18?0.  and  material.  the  Gold  of  stipulated of the  the  of  and  of  Stickeen  additions  Legislation with  the  Gold  sale  of  and  non-discriminatory  is  the  right  not an  would  water prices  by  not the  and  Fields  result the  were  evolve water  Act  water  years  British  Columbia  Charlotte  Islands,  to  a  as  at  to  water  rights  This to  riparian  the  British  rental  to  the  holder  charged.  non-use of  the  evolution legislation.  or  as  in gave  use  of This  Columbia  crown,  waste  right,  act  owner.  of  from  federal  administration  feature  pay  the  resource,  I859.  of  exclusive  important user  of  Queen  amendments  necessarily  water  Five  Canada  Territory.  regarding  grant  colony  Island,  administer  of  four  crown  provinces  that  allowed  the  Columbia did  water,  act  original  British  rights  his  province  Vancouver  Commissioner to  riparian  cancellation  union  Act.  quantities  sixth  confederation  series  Fields  the  joined  the  Columbia began  to  defined  as  specific  with  and  Columbia,  because  Gold  power  of  C o l u m b i a became  previous  took  of  Conference  Columbia  I87I,  level  described  development  scientific  British i n  p r o g r a m was  Premiers"  of  and  that  water.  long  as  law.  The f a i r  99 The Water Privileges Act of 1892 dealt with water uses not covered by the Gold Fields Act nor the Land Ordinance of I865 which concerned irrigation. The importance of this act i s the declaration that a l l water i n streams belonged to the province. The objective of the Water Clauses Consolidation Act of 1897 was to consolidate the various laws dealing with watero  I t also stated what had  been implied i n earlier l e g i s l a t i o n that water rights were conditional on reasonable use of the purposes for which the rights had been granted.  This  provision did not apply, however, to municipalities for water works systems. Water acts.  The f i r s t Water Act by that name was enacted i n 1909° I t  created the Board of Investigation to hear claims of a l l persons holding water rights and to prescribe the terms for new licences.  Amendments to the Water  Act, i n 1913° divided the province into eight water districts each supervised by an engineer°  The amendments of 1914 further clarified the principles  established by earlier legislation, and definitely ended any riparian rights for which licences had not been granted before June, 1916, The Board of Investigation, established i n 1909° was abolished by the Water Act of 1939» and most of i t s functions were vested i n the Compt r o l l e r of Water Rights,  This act has changed l i t t l e since 1939° one of  the most important changes being an amendment i n i960 to include ground water i n the act.  In the past few years studies have been carried out on  ground licencing and procedures and recommendations have been drawn up. No ground water licences have yet been issued. Water Resources Service,  In I962, the Department of Lands and Forests  Amendment Act created the Water Resources Service responsible for the administration of the Water Act and a l l matters pertaining to the water resources  of  the  from  province.  the  Department  irrigation  for  Oliver, In  of  B.C.  and  from  Dykes  the  Res.  this  the  Water  administered  land  and  Project  Resources by  provides  the the  was  transferred  Service.  province, domestic  of  i n  AGENCIES  the  B.N.A.  act  i t s  division  but  i t  of  of  of  the  Affairs,and  Agriculture  (B.C.  This  serves  water  supply  resource  necessary  administration  The  certainly  is  number  of  influenced  responsibility  can  hardly  be  blamed  The  number  of  agencies  between  for  the  some  were  the  Nat.  taken  many  on  Board  Office Res.  problems  by  was  of  the trans-  Inspector  Conf.  federal,  for  and  an  the  1964|  provincial,  appreciation problems  involved  number  federal  the  RESOURCE  of  agencies the  of  1957).  Shelley  responsibilities  water  on  Pollution-Control  A D M I N I S T E R I N G T H E WATER  regarding  water  has  when  Municipal  various  administration.  The  I965  began work  responsibilities  1964, 1965, 1966;  Serv.  of  Service  Increased  Department  agencies  complexities with  Okanagan Lands to  Resources  Department  Knowledge other  Water  Service  3.  and  and  irrigated  erosion.  the  from  Water  Agriculture  developed  of  the  1964  Resources  ferred  South  B.C.  flooding  Water  of  acres  the  196-3 of  project,  5»000  about  In  of  i s  at  the  associated remarkable.  agencies  and p r o v i n c i a l  agencies  of  because  of  governments,  both levels  of  govern-  ment.  implications  of  purposes  as  that  agency  one  water  domestic  i n  our  dealing daily  supplies,  should  with  l i v e s .  i r r i g a t i o n ,  administer  the  water  is  indicative  Water  is  used  and h y d r o  resource  for  for  power,  all  three  of  such and  to  uses  the diverse suggest would  be  101  Q  extreme.  This i s not to suggest that the present administrative set-up i s  the most efficients, nor that overlapping and omission do not occur. Federal Agencies The main source for this and the following section i s the background paper for the Resources for Tomorrow Conference by Patterson ( 1 9 6 2 ) ,  Until  recently, ten separate federal departments were directly involved with the water resource.  These included Agriculture, Fisheries, Forestry, Mines and  Technical Surveys, National Health and Welfare, Public Works, Northern Affairs and National Resources, Transport, Trade and Commerce;, and External Affairs,  In addition, eight other federal agencies were involved!  Atomic  Energy Control Board, Canadian Maritime Commission, National Research Council  8  National Harbours Board, Central Mortgage and Housing Corporation, Saint Lawrence Seaway Authority, Northern Canada Power Commission,, and the International Joint Commission, These agencies carried out work involving surveys and mapping of the water resource, research, administration and regulation, engineering, liaison, negotiation of agreements, and advisory functions.  Of a l l federal agencies,  the Water Resources Branch of the Department of Northern Affairs and National Resources has been involved with the water resource to the greatest degree. Its chief duty has been the collection of data as well as administering the Dominion Water Power Act and regulations dealing with water resources of the Yukon and Northwest Territories, national parks, and Indian reserves, A brief summary w i l l be given to indicate the agencies involved with various aspects of the water resource.  There i s considerable overlapping of  responsibility even between agencies at one level of government.  102 Five federal departments are involved with the water resource under the topic of navigation, but only two of these, Public Works and Transport, have responsibilities which go beyond basic data collection.  Concerning  flood control, six departments are involved, five of these with basic data collection and five (Northern Affairs and National Resources, Agriculture, Public Works, Transport, and Mines and Technical Surveys) with further responsibilities.  Agriculture i s the only department concerned with i r r i g -  ation, other than basic data collection i n which five other departments are also involved, Five departments are involved i n power development, only one of which deals solely with data collection.  Seven departments deal with domestic and  industrial water supplies of which the responsibilities of three (Northern Affairs and National Resources, Health and Welfare, and Agriculture) go beyond data collection.  The Fisheries department alone has responsibilities  concerning fisheries beyond data collection, for which five other departments are also involved. In pollution control, seven departments are involved, four (Public Works, Fisheries, Health and Welfare, and Trade and Commerce) to an extent greater than data collection.  Three of the five departments concerned with  watershed treatment deal with the water resource i n ways other than as data collection agencies.  The departments are Northern Affairs and National  Resources, Agriculture, and Forestry, and their responsibilities include erosion control, soil programs, and reforestation.  Two of these departments,  Northern Affairs and National Resources and Agriculture, with the Department of Fisheries have responsibilities i n recreation and wildlife i n which three other departments are also involved i n data collection.  103  In Surveys  1965s  united  Resource  was  to It  form  was  and  i n  energy  following  the  and  Resources, f i e l d .  of  in  with  be  forms been  and  The  to  Minister,  with  in  and  the  same y e a r  Affairs  the  Technical  and  Water  a  National  Resources  Surveys. a  new  department,  coordinate i n  Mines  Northern  along  that  19°5»  created  is  new  of  the  his  energy  a l l  that  national  announcement,  is  needed,  needed  more i n  importance  water  Legislation  following  the  and  National  Development  These  changes  administration  of  a  decrease  administration  Provincial  of  of  the  Resources  p.  of  activity  made  the  one  the  i n  is  generally.  created  Department  concern  the  and of  12).  the  The  remains  make  particularly  became  resources.  of  resources  Technical  the  Canada  to  provinces  coordination  policy  of  federal  and  reflect  energy  number  of  Mines  1966).  i n  to  a  both  the  announcement  (Prince  water  activities  is  out  order with  relation of  1966,  Resources  i n  of  focus  effective  (C.AoA.E.  and  One  cooperation  and  and d i f f e r e n t  responsibility  notable  In  of  of  Later  Technical  ministers.  closer  industry  policy  i n  and  December,  Prime  responsibility  result  Branch.  Department  Mines  The  have  possible  resource  Department  transferred,  to  departments  Northern  the  Research  the  was  Different  Affairs  in  explanations  sources  Energy  of  then  Department announced  units  Water  Branch  created  the  Energy the  to  separate  Development  Resources Branch,  five  of  the  effect  to  be  number  on  Department  Surveys, of  federal  seen,  of  the  and  Indian  but  federal  Northern  Affairs  government  coordination the  of  of  least  departments  and  with  the  water  that  w i l l  involved  resource.  Agencies the  province  of  British  Columbia  administration  of  the  water  resource  104 is  primarily  Department the  Water  water two  of  resource.  governs  the  province.  and  two  with  the  departments: Finance. Lands,  Finance,  and  and  and  involved  Resources,  and  Recreation  which  includes  the  and  Department  Public  of  Utilities  Water  Resources,  under  the  and  heading  Federal-Provincial As water  control  well  resource  as  f i e l d  and  the  and  soil  commissions.  Lands,  Recreation  and  and  there  are  provincial  Lands,  well  with  a l l  of  the  agencies  Forests,  of  the  and  and  administer  control. and  treatment, is  the  Lands,  of  Resources,  Forests,  programs,  of  and  Public  Water  Lands,  Resources,  four  departments  as  is  and  Agriculture,  Watershed  departments  of  pollution  development  Water  the  Forests,  departments  Conservation  administered  responsibility the  B.C.  Forests, the  water  Hydro and resource  wildlife.  International distinctly  of  departments,  Highways,  as  dealing  Power  The  the  conservation  and  required  other  concerns  Finance,  of  the  administers  responsibility  Conservation.  Forests,  recreation  the  by  Agriculture.  Lands,  and  and  responsibilities  Water  of  is  supply  departments  service  the  administration  control,  water  have  department,  flood  industrial  Resources,  of  province.  Resources,  administered  single  i n  with  indicating  the  This  five  Water  are  a  concerned  Service  licences,  however,  Irrigation  Fisheries  by  water  and  The  erosion  of  summary of  Resources  Resources.  are,  also  resources  Water  Health  Water  issuing  There  Forests,  Commission. and  the  brief  are  the  and W a t e r  Highways.  Lands,  Forests,  a  water  Domestic  U t i l i t i e s  is  departments  Resources,  of  commissions  Following  Two Water  Forests,  which  in  boards,  responsibility  Lands,  Act  users  involved  the  Agencies  federal  the  or  provincial  federal-provincial  agencies agencies,  active  i n  the  inter-provincial  105 agencies, federal effect  and p r o v i n c i a l  government. i n  1964,  Of  agencies the  program  federal-provincial  69  concerned  23  receiving  the  water  resource  assistance  resource  (Can.  from  the  agreements  Coun.  Res.  i n  Ministers  1964). Federal-provincial been  undertaken  established  to  the  the  Lake  of  from  Provinces  Water  as  River the  Woods the  agencies  floods,  a  been  the  Development  and  government  i s  an  arrangement.  Some  the  and  of  of  part  the  e.g.,  a  such  Saskatchewan  agreement of  water,  Board.  situations  South  been  Prairie  Conservation  The  type  have  basis,  agreement),  emergency  Board.  constructs  agencies  have  program i n v o l v i n g  Forest  with  the  management  continuous  Woods  deal  Dyking  a  joint  Rockies  to  example  on  f i r s t  of  Eastern  finances  water  (the  Lake  Valley  i n  function  established  Fraser  Board  the  activities  of  Board  Canadian  1921  have  types  particular  Control  Board,  e.g.,  federal  various  perform  resulting  Other  under  cooperative  under  which  water-development  project.  2,000  About navigable crossed  and  by  waters  and  Treaty  of  a  number  to  River Lake as  Board Board  the  Board.  rivers.  arbitrate provided  1909  of  To  of  of  Control. River  the  avoid  those for  the  Canada-United  rivers,  the  and  the  States  that  do  have  Rainy  been Lake  Engineering Engineering  out  of  of  the  the  Board  and  of  have the  the  the  marked  miles use  of  these Waters  International  including  Control, also Saint  and  been John  of  the  Joint  the  the  commission  St.  Lawrence  Kootenay  established River  by  are  Boundary  functions  established  boards  Board  arise,  are  3,000  regarding  establishment carrying  border  remaining  controversy  problems  the  control  Control,  Columbia  To  facilitate  boards  of  of  non-navigable  many  Commission.  miles  such  Engineering  106  Other  Agencies Many  are  agencies  interested  i n ,  administrative government, some  are  the  districts  the  works,  the  the  case  licences  they  such  no  British  described  of  the  11  of  orderly  nor  senior  the  their  Greater  and  the  Crown Water  although  own  agency,  governments.  development  of of  The  Canada's the  the the  Resources  i t  levels  of  and  own  These  supply  and of  owns  the  must  are corporoperate  water  Water  province,  obtain  to  out-  V i c t o r i a  of  use.  their  Examples  d i s t r i c t  right  have  derive  Greater  District,  as  water  Service.  and m e t e o r o l o g i c a l ,  comprised of  earlier  the  these  is  carried  out  use.  responsibilities. an  in  their  construct,  adequate  governments  boards;  Victoria.  purchase,  does  for  government.  an  of  higher  charters  Whether  as  hydrometric  their  to  Some  advisory  Greater  furnish  watershed,  both  i n  and  d i s t r i c t .  Vancouver  executive  attention  Vancouver  from  as  federal  the  collection  provincial  to  from  provincial  Columbia Water  for  agencies,  the  derive  data  or  resource.  function  of  with  required  area  collection,  policy-making  of  the  the  some  provincial  water  they  own l a n d  munioipal  governmental  Ministers,  much  the  to  are  organizations Some  have  of  from  the  the  extent  Greater  within  leases  from  Data by  and  or  of  of  which  u t i l i t i e s  authority  complete  District,  the  resource  municipalities  right  i n  the  the  to  public  over  water  with  provincial;  only  authority  have  those  and i n v o l v e d  especially  Municipal  ations  than  responsibilities  involved  water  other  representatives  The  Canadian  section, but  i s  council  is made  one  of  Council  example.  up  concerns  renewable  council,  an  from  of  the  government,  of It  Resource is  resource  i t s e l f  with  Water  has  whose  projects  a  ministers  the  resources. major  neither  promotion received  was  the  10?  collection i n  i s  of  basic  data  concerning  the  administration  of  the  water  resource  Canada* The  Canadian  another  example.  and  universities  the  promotion  source  addition  i s  limited  power  companies  tion  districts*  grain  to  to  the  do  i n  use so  of  i n  water  to  the  for  out  of  i s  on  the  As  standards  the  probable  intangible  value  of  of  that  values  l i v i n g  natural  of  rise  i n  as  and a s s i s t  however,  l i m i t  future of  the  resulting from  much more nations  i n the  resources,  higher point  incomes of  view  objectives  development  and  management,  as  well  the  more  industrial,  power,  past*  as  reof  e.g.. conserva-  are  irrigation  activities  e.g.,  owners  emphasis  the  the  Some  surveys;  their  resort  achieve  i n  snow  observations,  forecasting;  water  data.  and p r e c i p i t a t i o n ,  To  than  the  analysis.  i n  increase.  heavily  with  meteorological  will  more  include  with  prairie  and  private  DISCUSSION  many  domestic  objectives  concern  aesthetics,  and  governments  interest.  the  resources,  federal  Decade  program.  meteorological  4.  It  well  Hydrologic  and  its  minimum o f  levels  crop  but  whose a  category,  resource data  IHD  with  stations  this  agency  agencies  as  International  from provincial  Canada's  many  gauging  simply  the  governmental  collection  i n  of  members  hydrometric  groups  water  companies  individuals  a  interested  Most  of  are  data  operate  are  up  not  there  interested  groups  regard  is  Committee  supervision  In  are  Made  i t  and  these  National  uses  as of  Even i f  water,  of  familiar government  Canada's  water  be  placed  especially  and of  w i l l  more  leisure  recreation this  aspect  aspects w i l l  resource  water.  such  be  time  and of  water  as  relied  on  administration  108 i s  adequate  for  the  satisfy  the  needs  not  present, of  and  the  there  future  i s  evidence  unless  i t  i s  to  the  contrary,  substantially  i t  w i l l  improved.  Problems B.N.A.  Act.  The  to  develop  responsibility In  most  i s  i n  enterprises,  the  also.  developmental even  after  enterprises  does  not  succeeding right  tributed One  to to  a a  large  at  the  Water  Conservation  federal  assistance  have  interpretation to  to  writers  and problems  allowed  stage.  part extent  has  the  the  to  the  Assistance  the  arisen  The  return  government  under  water act  the  the  of  by  An the  the  B.N.A. the  enterprise  This  has  the  and  con-  resource.  agreements  i s  provinces  act  government  water  shared-cost  f i e l d ,  resource  federal  the  act.  B.N.A.  taxation.  example  and  resource  The  the  managing  the  which  to  right  natural  revenue.  given  the  when  natural  f r o m many  raised  i s  by  revenues  as  have  d i f f i c u l t y  Act  occasionally  continue.  the  given  resources  i n  governments.  B.N.A. from  true  d i f f i c u l t y  the  own  been  exceed  revenues  and p r o v i n c i a l  of  i s  agreements  this  develop  their  This  to  of  Canada have  greatly  development,  overcoming  tween  The  inputs  accrue  large  of  manage  federal-provincial  attempt  c i a l  and  money  But,  the  provinces  be-  Canada  receive  finan-  resource. could  need  to  resulted  jurisdiction  of  not  foresee  interpret in  a l l  the  unresolved  off-shore  of  its  act.  Doubt  situations  o i l  implications  rights  i s  as  to  the  being a  current  example. Provincial of  managing water  rights.  The  attitudes.  Another  i s  with  the  zeal  federal-provincial  responsibility  i n  that  the  factor  which  some  shared-cost  federal  contributing of  the  programs  government  has  had  to  the  d i f f i c u l t y  provinces  guard  also  shared  a  mean  hand  in  their  framing  the  109 terms made the to  of  the  agreement.  available resources  without are  compromises  benefits  may  be  Federal role but  i n  the  often  and i t s the  be  which  lack  of  from  are  also  of the to  be  number  directed  to  the  collection  for  their  departments, means  that  immediate logical that  to  data user,  data  extreme  i t s  use  any  of  that  legitimate  responsibility although  has  The  to  this  money  i n  be i f  may  some  lead  cases,  responsibility. long  on  was  taken  reasons,  administer  encroachment  belief  federal  perhaps  suffers,  rights  that  Divided  resource.  1  is  government  Coordination is  involved of  opposite  than  in  these  the  any  and  values  have  is  a  real  i t s  passive  or  own  of  imagined,  resources  rights.  w i l l  has  phase  or  been  a  been  and  However,  the  people,  water  due  nature  of  their  section the  needs  of  another  designed  to  f i l l  future  needs,  sufficiently  sampled  and  that  omission i s more  management.  i n  long  to  overlapping;  probably  preceding  the  i s  the  are  between  This  complete  gaps of  of  especially  s  satisfy  period  result  and  particular  not a  use  overlapping  one  i n  lacking  resources.  another;  other  the  does  cover  the  described  collection  must  is  particular  satisfy  to  effort  sometimes  water  Duplication  agencies own  and  ends  collection.  data-collecting data  water  administering  Duplication  Data data  i n  agencies  b i l i t i e s .  federal  allow  provinces  or  leadership.  involved  of  to  division  provinces '  the  Administration. agencies  the  as  the  management  such  The  by  efficiently.  resource  attitudes.  unwillingness may  managed  derived  stated,  demands  stipulations  management  reasons  just  by  to  The  one  case  the responsieffort a  third.  apparent  Many  are  many  of  i n  the  collecting of  user. need,  government This that  Hydrometric  and i s  often of  the  meteoro-  that  the  user  confident  averages  are  representative  of  110  long-term The  averages,,  result  is  a  Another i s  that  waiting problem  potential  clearing  The  house  period  are  data  of  of  before  resulting  users  for  collection  from  often this  data  often  the  data  the  number  unaware  nature,  are  that  and  begins  when d a t a  are  neededo  available.  of  data-collecting  data  do  numerous  exist.  data  agencies  There  are  is  no  unpublished.  Recommendations Recommendations exist  i n  views. that  a  administering One  strong  diction  over In  a  view  the  water  diverted  to  be  chairman c a l l i n g  of for  ordination  1965)• stated " i t  T^ his  must  a  of  a  their  the  act  i s  in  view  that as  a  a  on  water to  been  water  This  be  i n  which  based  on  necessary; of  the  the  problems  either  of  other  i s  provinces'  scheme  federal the  two  j u r i s -  role  the  resulted  as  in  well  water  General  stated  proper  management  that  about  proposal would  Canada's  resource  A,G.L.  of  an  be  water-export  of  Turner,  federal  the  federal  government must must,  the  minister  on  guidance  resource  behalf  not of  former  Commission,  without act  administration  McNaughton,  Joint  federal  John  and  the  northwest  as  International  policy  coordinator  from  Canada  section.  subject. of  much d i s c u s s i o n i n  from Canada's  subsequent  section  essential  belief  now  can  role  probably  which  strong  Canadian  Honorable  6  situations  resources  has  has  States.  views  national  were  the  federal  there  by  discussed i n  expressed  of  unacceptable  This  firm  United  Supporters have  i s  years  policy.  engineering  w i l l  water  strong  role  few  American  policy  a  some  resource.  l a s t  the  improve  Canada's  that  federal  the  national  i s  to  and  i n  co-  (McNaughton  portfolio, only  the  as  people  a  referee, of  Canada,  I l l  bring  provincial  coordinated  view. of  national  On  the  other  In  19&5,  guidelines  to  consistent  council 10  of  i s  that  are  the  provincial-rights The Lands,  i n  a  can  c r i t e r i a , the  i n  be  the  years.  appear  that  "A  i s  this  federal  w i l l  the  for  from  the  stated  broadest  11  the  opposite  Included  B.N.A.  a  set  was  the  governments act.  senior  should  Since  the  governments,  consistent  for  his with  view  with  made  the  that broad the  future  Columbia of  regard  statement  (Williston  situation has  British  investigation  administered  adequate  the  of  recommended  cooperating  the  policy  agencies"  have  the  under  of  careful  the  into  the  1966).  national  government  be  support  recommendation i s  minister  exactly  governments  this  of  ministers  with  scope  i n  programs.  Resources,  provincial  this  The  provincial  water  f u l l  responsible However,  many  Water  raised  federal-provincial  Williston,  concerned  leaving  of  ( C A . A . E .  Vancouver:  only  been  Ministers  resource  and  persuasion  Resource  provinces,  R.G.  and  1965).  responsibilities  attitude  Forests,  speech  then,  to  Hon.  initiative  responsibilities  their  composed o f  which  of  the  have  Council  joint  by  (Turner  voices  Canadian  govern  with  together  policies" hand,  the  recommendation be  governments  the to  of and  Department  federal  water  pollution,  objectives sound  role  and  judgement  I966). has  been  i n  statements  resource.  existence of  It  administration  policy  does of  for and  not the  resources. Federal  for  the  the  past  accepted  l e v e l .  national must by  be  the  The  proper  good r e q u i r e s given federal  up  and  a  administration strong  federal  responsibility  government.  for  of  Canada's  role.  The  i n i t i a t i n g  water  resources  passive  role  of  action  must  be  112  To the  secure  federal  the  government  reporting  directly  with,  be  but  mittee for wide  i s t s the  i n  the  all  Department  is  probably  provide  water  the  of  water  be  of  members  the  f i e l d  water  of  resources  has  i n  already  and Mines  containing  branches.  The  the  committee  of  chosen but  closely  the not  comso  for  much  their  composed o f  formed.  Water  special-  Reorganization  management  the  Consolidation  size  which  resources.  committee  with  i n  s h o u l d work  resource  resource  begun  policy  high-level  being  water  s h o u l d be  water  a  It  departments.  individual  the  water  role,  formed.  interdepartmental  involved  This  should  phase  i n  a national  leadership  government  single  an  a  for  should  establishment Research,  to  an  even  as  an  advisory  be  of  Water  of  the  Resources,  greater  extent  necessary. interdepartmental between  federal  can  assigned  persuaded The  to  the  the  government,  such of  At  even  to  the  a  act  apply  necessity  should not  and  resources  water  for  board  and  by  l i m i t  a  extent  mutual level  willingness of  to  existing  pollution.  The  uniform legislation federal  responsibilities  provincial and  its  problem i s  government  the  resource  then  the  act  rights  federal  level. water  of  should  agencies.  should  B.N.A.  provincial  Provincial of  government  be  control.  because  federal  example  pollution fields  committee  An  should  federal  a  Development  provinces  awareness  of,  level  Energy  problems.  be  of  f i r s t .  l i a i s o n The  cabinet  experience  next  of  assume  small,  departments  Resource  The  and  fields  federal  the  kept  knowledge  accomplished  and  be  knowledge At  to  foundation  would  independent  should  their  proper  foregoing  i n  particular  such  areas  agreement.  the to  i n  action  for  need  i s  for  cooperate some  degree  increased  with of  the provincial  113  rights water of  i n  the  comprehensive  is  no  valid  provinces  as  continental  fact In  resource Lands*,  seems  necessary,  British rests  Act  and  increased  Water  The  aspects  of  l o g i c a l  one  i n  ment  the  provincial  of A  service  which  commission  established  having  development  and  commission  resources  Ontario  was  In  members  were  1964 the  departments,  and  resources  as  national  resources.  Department  of  includes  water  the  the  supply  staffed  province  But  for  water of  control*  to  handle  especially  schemes  this  of  investigations,  and p o l l u t i o n  diversion  control.  the  administration  assumed r e s p o n s i b i l i t y  authority  possible.,  Service  adequately  of  be  of  districts,  resources  resources  administration  function  yet  the  demanding  for  certain  agency  management  with  is  the  and  develop-  level  should  resource. to  that  proposed for  responsibility directly from the  Saskatchewan deputy  not  pollution  to  the  for  f i r s t for  premier.  created  ministers  of  Canadian a l l a  resource The  province  similar  from  federal  agencies  aspects  Natural  representatives  the  water  non-government  commission responsible  1966)o  Health  drawn  is  greater  water  similar  be  should  for  of  water  i t  licensing),  recently  vest  overall  Its  the  but  and proposed water  e.g*,  reporting  should  departments,,  to  these  and management  considering  resources  improvement  water  only  resource,  for  Resources  0  water  Service  the  has  manage  Water  of  growth  study*  reason  Resources  through  of  industrial  the  the  Resources  planning  to  development  responsibility  supervision  Water  overall  with  (mainly  planning, The  Columbia,  mainly  Forests,  Water  basin  There  Canadian  and i n  the  of  resource*  the  the  interest  of  of  the  as  as  government  water  South  well  establish  commission  the  and  members  to  Resources,  planning  be  a  water  resources  (CAoAoE.,  and  as  named  Agriculture, Saskatchewan  and River  114  Development Commission, Saskatchewan Power Corporations and the provincial Economic Advisory and Planning Board (Regina Leader Post 1964).  Members of  the British Columbia commission should be from similar agencies,, The British Columbia Water Resources Service should be responsible to a much greater degree for the management and development of the water resource and for coordination of the activities of the various agencies concerned with the water resource,, be employed  To carry out this task, specialists should  from fields other than just the engineering and hydrology  fields, e.g., economics, forestry, and regional planning. Data collection.  I f , instead of many government agencies being respon-  sible for data collection, one agency were responsible for hydrometric data and another for meteorological data the system would be much more efficient. The future needs for data on the water resource could be anticipated to a greater degree than at present and the type of data and the method of collection could better serve potential users. Once observations of a particular phenomenon are begun they should not be dropped without careful consideration. Streamflow records are available for some streams for very short periods interspersed with many years for which there i s no record.  The original observations were probably begun  with a single need i n view and when data were collected to satisfy the need the observations ceased.  However, the short period of record has made even  more valuable any subsequent record. One agency should have the responsibility of collection and publication of hydrometric data, and another for meteorological data.  This task should  logically f a l l to the federal government, two of whose agencies, the  115 Meteorological and Water Resources branches do the greater part of basic s  data c o l l e c t i o n  Data should be published more often and receive wider  distribution so that current information i s readily availableo The need for more extensive coverage for hydrometric and meteorological observation i s especially true of British Columbia.  Observations  at higher elevations are important because a large proportion, of streamflow originates there as precipitation.  More research on long-term recording  instruments for use i n remote locations would be well repaid. A good start has been made i n extending the climatological network as an A.R.D.Ao (Agricultural Rehabilitation Development Act) project. In  1965?  temperature and precipitation stations were established (many along  altitudinal transects) i n the Prince George and East Kootenay areas. In 1966 effort was concentrated i n the East Kootenay area and measurements of s o i l temperature and evaporation were begun. Additional altitudinal transects for precipitation were established near Nelson^ Kamloops  9  Smithers  3  and north of Prince George. In 196?8 the climatological network w i l l be extended, to the Peace River area Terrace (Schmidt  B  Fort Nelsons and between Vanderhoof and  196?).  The Research Division of the BoC. Forest Service has been working on long-term recording instruments and a prototype constructed by Sperry Gyrascope i s presently being tested on the campus of the University of British Columbia (Schmidt  196?).  However i n view of the need for hydrometric 9  and meteorologic data more resources should be devoted to such research.  116 CHAPTER IV,  WATER RESOURCES OF BRITISH COLUMBIA 1»  CLIMATIC REGIONS  The difficulty encountered i n delineating climatic regions i n British Columbia i s that, because of the mountainous terrain, variations in climate are greater with elevation than with horizontal distance. For example, i n an area south of the Crowsnest Pass, winter (October-May) precipitation averages 20 i n . at 4,400 f t . and 40 i n . at the 5,200 f t . elevation (Gray et a l. 1965). Some division of the province i s necessary for discussion of climatic regions,  Kendrew and Kerr (1955) established the following climatic regions  for British Columbia: and Northern,  Littoral, Southern Interior (eastern and western),  This classification i s based on observed differences i n  climate as well as physiographic divisions which help to explain the climatic differences.  But the classification i s not based on defined  limits of such climatic factors as precipitation and temperature. Another system of delineating climatic regions i s by enclosing those areas having approximately the same values for a particular climatic parameter such as precipitation, temperature, and length of growing season. The ARDA classification of climates for agriculture (Can. Dept. For, and Rural Devel. I966) produced maps of (1) temperature zones (seven classes) based on the number of degree-days above 42°F. per year, (2) moisture zones (nine classes) based on a combination of water deficiency and summer precipitation, and (3) climatic regions for agriculture based on a combination of (1) and (2),  117  The division o f British Columbia into climatic regions according to the classification developed by Kcppen distinguishes eight regions based on temperature and the amount and distribution throughout the year of precipitation (Can Depto Mines and Tech» Surveys 1 9 5 7 ) ° 0  These classifications satisfy to a greater or lesser degree the needs for which they were devised, but they are not very useful for consideration of water resource management. Nor i s any one classification likely to present a complete picture of the water resources i n British Columbiao  The  information presented i n Maps 1-5 °n the following pages does provide to a greater degree the means of assessing the water resources of the province. Preeipi tation Amounto  Map 1 contains the isohyets of mean annual precipitation  for British Columbiao  An estimate cf the mean annual precipitation f a l l i n g  on the whole province was obtained by planimetering the area within each isohyet and applying the indicated precipitation to this area  0  The average  precipitation i s about 4-5 in« annually, or 880,000,000 acre-feet. The limitations of the precipitation calculation, as well as the following calculations based on Maps l=5n roust be mentioned,-, Aside from th© accuracy of the meteorological observations involved there i s the problem of forming isolines of various parameters where large areas have not been sampled,, as i s the case i n British Columbiao  Potential and actual  evapoTranspiration and moisture d e f i c i t were estimated by Thorn thvaite s 11  (Thornthwaite and Mather 1955) method and are another possible source cf erroro  Some obvious discrepancies are noted i n following sections and may  be due to these factors.  Even with the possible inaccuracies i n the  RESOURCES MAP NO.  119 estimates they do provide some insight into the water resources of the province. Annual precipitation varies greatly across British Columbia, from lows of 7«55 i n . (30-year average) at Ashcroft i n the Thompson River basin, 8,94 iru (15-year average) at Alexis Creek i n the Upper Fraser River basin, and 9°0? i n . (34~year average) at Merritt i n the' Nicola River basin, to 145 69 i n , (30-year average) at Seymour Falls near Vancouver, 167.52 i n . 9  (six-year average) at Holberg on western Vancouver Island, and 174.32 i n . (30-year average) at Ocean Falls on the North Coast (B.C. Dept. Agric. 1964), Of the total of 880,000,000 acre-feet of precipitation f a l l i n g annually i n British Columbia, half of i t i s received by only 20 per cent of the land surface.  At the extremes are the 39 per cent of the province  which receives 20 i n , and less precipitation, or 15 per cent of the total, and the five per cent of the province receiving more than 150 i n . , or 16 per cent of the total, as shown i n Table 2. Table 2,  Ratio of class area to area of British Columbia and class precipitation to total precipitation by mean annual precipitation classes  Mean annual precipitation i n inches Less than 20 20 -  Ratio of class area to area of province i n per cent  Ratio of class precipitation to total precipitation i n per cent  39  60  41  15 35  14  60 - 100  8  100 - 150  7  Greater than I50  5  20  16  120 Rainfall regions may be described as follows., Least rainfall (12-20 i n . annually) i s received i n the Southern Interior of the province, with most of the Northern Interior receiving 20 i n . annually.  Along the mountains  on the eastern border of the province, mean annual precipitation ranges from 40 to 60 i n . , mainly, with small areas receiving up to 80 in= Highest rainf a l l i s received on the west coast, a 50-mile-wide strip from Vancouver to Alaska receiving over 100 i n . Within this coastal strip i s a discontinuous strip 40 miles wide which has a mean annual precipitation of over 150 in„ Most of Vancouver Island receives more than 100 i n . of precipitation annually.Seasonal distribution.,  The data used i n the analyses of precipitation  and actual and potential evapotranspiratlon are mainly long term averages of annual values.  Of more importance i n many cases i s the distribution of  precipitation throughout the year.  Regions of high annual precipitation  may suffer summer drought, whereas regions of low total rainfall may support crops because of the distribution of precipitation.. Data on seasonal precipitation show that most of British Columbia receives less rain during the spring and summer than the amount of potential evapotranspirationo  Combining seasonal precipitation data (Can. Dept.  Mines and Tech. Surveys 1957) with annual data (from Map 1) provided the information presented i n Table 3° Potential evapotranspiratlon, which will be discussed i n the following section, i s also shown i n Table 3 and has been derived from Map 2.  121  Table  Spring-summer  3*>  annual  precipitation  precipitation,  British  i n inches  and p o t e n t i a l  and as  a percentage  evapotranspiration  of  i n  Columbia  Mean S p r i n g - s'ummer precipitation  Location  in  annual  Spring-summer  potential  inches!  precipitation  evapotrans-  as  a  piration  of  annual  i n  inches  percentage  Southern  Columbia  0  12-14  18-20  30  Northern  C o l u m b i a Mtso  14-16  16-18  Southern  Interior  6-10  20-24  35 50  Northern  Interior  8-10  18-20  45  14-20  18-20  17  20-30  18-20  20  Mts  pre-  cipitation  Coast  52°No  -  54°No  49°No  -  52°No *\  54°N  -  57°Ho  0  Sources  The is  lowest  Mountains cent)  support  region 3)°  of  (30-35  Canada  annual  region  amounts  which  whether  i t  only  o r exceed  crops  Another  may o c c u r  (17-20  per cent),  Mines  i n  followed  region  coastal  region  Reso  aspect  do n o t r e q u i r e Confo  1964)  be f o r i r r i g a t i o n  o r hydro  power  or less  than  a n d summer the  Columbia  (45-50  per  and  generally  irrigation  to  0  i s  the water  f o r example,  specified  1957)°  spring-summer  of precipitation  f o r the use o f  greater  does  evapotranspiration,  planning  precipitation  by  the  In  0  spring  f o r the I n t e r i o r  Nato  important  i n  Surveys  and highest  River  (BoCo  Techo  and  falling  per cent),  the p o t e n t i a l  and the Peace  agricultural  (Can. Dept.  precipitation  region  However,  equal  Extremeso  of  of  f o r the coastal  (Table  this  Atlas  proportion  precipitation only  J  amounts  the must  the  extreme  resources,  probabilities be  consideredo  122 As an indication of precipitation extremes i n British Columbia, Kendrew and Kerr (1955) expressed the range between the maximum and minimum annual precipitation as a percentage of the mean annual precipitation.  These per-  centages range from 58 to 96 for selected coastal stations, 60 to 119  for  the Southern Interior, and 68 to 88 for the Northern Interior. As an indication of the extremes that have been recorded i n the province the following are taken from Kendrew and Kerr (1955)• to 1950,  1915  From  the lowest May-September precipitation recorded at Victoria was  less than 0.3 i n . and the greatest was 4 9 in.; at Prince Rupert, 4.7 i n . 0  and 60.3 i n . ; at Kelowna, 0.9 i n . and l3»8 in.; and at Prince George  s  2.9 i n . and 22.0 i n . Kendrew and Kerr (1955) tabulated the percentage of years i n which annual precipitation of specified amounts had occurred i n British Columbia. O'Riordan (1966) gave the probability of monthly (for the months of April to September) precipitation amounts for Southern Interior stations.  For  example, at Penticton there i s a 50 per cent probability of receiving i n . of precipitation, or less, from May probability of receiving 1.14  4.45  to September, a 10 per cent  i n . or less during that period, and a 90 per  cent probability of receiving 9<>76 i n . or less. Intensity.  Murray (1964) presented rainfall intensity maps of  British Columbia for six and 24 hour durations, and 2, 5, 10, return periods.  and 25-year  (The return period i s that period within which a storm of  given intensity may be expected to occur).  Because of the very sparse  recording precipitation-gauge network and the great area! variability of rainfall i n British Columbia, rainfall intensity-duration-frequency maps  123  were not presented for durations less than six hours. Most of British Columbia may expect a 24-hour rainfall of 1.00-3.00 i n . within a two-year period, but up to $.00 i n . may occur i n the Coast o . o , Mountains between 51 ^» and 53 N. latitude, and 6.00 i n . on south-western Vancouver Island and P i t t Lake near Vancouver.  For a return period of 25  years, the intensity of a 24-hour rain increases to 2.00-4.00 in. for most of the province, 8.00 i n . on south-western Vancouver Island, and 12.00 i n . i n the Coast Mountains. For a six-hour rain and a return period of 25 years, 1.25-3«00 i n . may be expected over much of the province, up to 4.00 in. on Vancouver Island, and 6.00 i n . i n two small areas, hear Brittania Beach i n the south Coastal Mountains and between Ocean Falls and Kemano. The areas of highest rainfall intensity are also those having the greatest annual precipitation.  This would be expected, especially for  durations as long as six and 24 hours. .Relation to watershed management. Precipitation data must be supplemented by other information for effective x^atershed management. Flooding can occur anywhere i n the province i n spite of the low annual precipitation received i n the particular location.  Erosion, too, can occur i n  those areas having low annual precipitation and low-intensity rains due to other factors that are also related to flooding and erosion, such as topography, soil type, and vegetation.  The amount of water needed for  irrigation depends not only upon the amount of precipitation, but on i t s distribution throughout the summer, on temperatures during the growing season, and. on the type of crop.  124 Potential  Evapotranspiration  Potential the  earth's  were  surface  not limited  water by  evapotranspiration  surfaces  available  based  i n i n  energy,  manner  o r 379s>000»000 Isolines  the  northern  the  south  having  18 i n  Columbia i n the  Mountains  Southern 5L°N.  latitudes  the coast  About  Actual  Evapotranspiration  using  Columbia  PE, precipitation,  s o i l  moisture  s o i l  controlled  were  annual  PE i s  about  and solely  method  i s  obtained  f r o m Map 2  a n d amount  to  19  o n temperature,, 16-18  PE values,  and i s  Island,  18 i n . north  Island  reflect  (AE) i s  e  the mild  on the west 26  water  capacity  o f  coast values  not high  loss  i n the Thornthwaite  storage  areas  found  20 i n . f o r t h e The higher  o f  andthe  i n . , i s  winters,  For  No p a r t  f o r the remainder  o f 5L°N.  the actual  calculated  and moisture  i n  as l o w as 16 i n . and those  22 i n . a r e i n d i c a t e d  evapotranspiration  and t r a n s p i r a t i o n  from  from  I96I).  i t s dependence  The highest  and about  and Vancouver  i f  by the Thornthwaite  24 i n . f o r Vancouver  temperatures.  oration  PE i s  0  the t o p o f the Coast Mountains  summer  Actual  f o r evaporation  has values  on the east.  Interior,  place  f o r precipitation,  indicate  o f the province PE are at  take  loss  annually,,  o f the province  t h e Okanagan V a l l e y .  below for  0  described  acre-feet  would  o f day (Mather  PE f o r British  o f P E (Map 2 )  half  half  and length  as t h a t  the combined water  by v e g e t a t i o n  and i t s calculation  o f total  i s  that  as needed  and transpiration  on a i r temperature  t h e same  9  to the atmosphere  but available  Estimates  (PE)  of the  from  evap-  method by s o i l  126 (Mather 1961),  The value of AE obtained from Map 5 for the whole province  i s 15 i n . annually, or 287,000,000 acre-feet. I t might be expected that isolines of AE would be similar i n trend to those of PE, with highest values i n the Southern Interior where summer temperatures are high.  The opposite i s the case, with most of the province  (80 per cent) having annual AE values of 12-16  in., and the lowest values  (8-12 in.) i n the Thompson and Okanagan Valleys.  A narrow strip along the  coast and south-western Vancouver Island (eight per cent of the province) exceeds 20 i n , of AE, because water availability and length of season of evaporation (the Thornthwaite method assumes no evaporation when temperature i s 0°G. or lower) more than compensate for cool summers. Moisture Deficit The difference between PE and AE i s a measure of the moisture deficit, the amount by which the available moisture f a i l s to satisfy the demand for water at a particular location.  The difference between PE and  AE as obtained from Maps 2 and 5 i s four inches (92,000,000 acre-feet), whereas the moisture deficit obtained from Map 3 i s 2.6 i n . (51,000,000 acre-feet).  The previously described possible inaccuracies may be  responsible for a large part of this discrepancy. Because of the high PE and low AE i n the Southern Interior, the moisture deficit i s greatest i n this area.  Sections of the Okanagan  Valley, Thompson River basin, and Fraser Valley between Williams Lake and Boston Bar (four per cent of the area of the province) have a moisture deficit of 8-l6 i n , (17 per cent of the total moisture deficit of the  RESOURCES MAP NO.  B R T IS IH C O L U M B A I  n  MAP 4. BRITISH MAJOR  COLUMBIA'S  RIVER  BASINS AV. FLOW  AREA 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.  II. 12.  FRASER LIARD PEACE COLUMBIA SKEENA STIKINE YUKON NASS TAKU HAY ALSEK COAST  SO. Ml. 90,000 55,500  %  24.6  cf.s.  PER SO. Ml. TOTAL 1.28 115,000 60,000  49,500 39,500  15.1 13.6 10.8 5.7  0.92 1.33 1.59 2.00  66,000 90,000 42,000  9,500 8,000  2.6 2.2  6,500 3,000  1.8 0.8  1.89 4.13 2 00  18,000 33,000 13,000  21,000 19,500  2,500  61,500  5.3  0.7 16.8  1.95  1.00  2.00 7.32  (SOURCE: RESOURCES MAP NO. 8, BRITISH COLUMBIA ATLAS OF RESOURCES)  38,000  3,000 5,000  450,000  129  province).  Seventeen per cent of the province has no moisture d e f i c i t .  This region i s an 80-mile-wide strip running the length of the west coast, most of Vancouver Island, and the Columbia Mountains on the east side of the province. Over 80 per cent of the province has a moisture d e f i c i t of four inches or less. The moisture d e f i c i t i s a measure of the irrigation needs of a region.  O'RLordan (1966) estimated irrigation requirements for five  stations i n the B.C. Southern Interior using Penman's method of calculating PE and deducting from this the amount of water available to the crop from soil moisture storage and r a i n f a l l .  The following are the seasonal  irrigation requirements i n inches with those derived from Map 3» Mean Annual Moisture Deficit, i n brackets: Hope, 6.7 (6), Lytton, 25.8 (14), Penticton, 19.1 (12), Princeton, 15.1 (10), and Kamloops, 24.6 (14). O'RLordan's values are higher than those derived i n this thesis, but lower than the average water duty i n the Southern Interior which averages about 32 i n . (B.C. Nat. Res. Conf. 1964). The PE values for the Okanagan Valley average only 24-26 i n . (Map 2) or only 50-75 per cent of the amount actually applied by i r r i g ationists.  This seems to indicate that a considerable amount of irrigation  water i s l o s t by percolation beyond the root zone. 2.  RUNOFF REGIONS  The major river basins of British Columbia are delineated on Map 4, and the legend box gives the average flow per square mile for each basin. The basins themselves cannot be considered distinct runoff regions, nor  RESOURCES MAP NO.  131  can several basins be combined on the basis of similar average flows per square mile to obtain runoff regions  The rivers flow through regions  0  differing greatly i n precipitations PE, and AE, and the flow that originates at different parts within a basin varies greatly?  For example, i n the  Fraser River basin^ runoff at Ashcroft i s four inches annually (12 i n  0  precipitation minus eight inches AE) and at Stave Lake near Vancouver, 132 inc (150 ino precipitation minus 18 in=  AE)  0  Because runoff i s mainly the difference between precipitation and AE, and because AE i s f a i r l y consistent across the province at 12-16  inc  (80 per cent of the province has AE values in this range), the isohyetal map  (Map 1) may be used to indicate runoff patterns  0  Runoff values may  be obtained by reducing the value of the isohyets of Map 1 by about 14 in» Runoff regions may be described as follows-. runoff ranges from two to four incheso  For most of the province,  Runoff i s very close to zero i n a  small area i n t h e Thompson River Valley between Spences Bridge and. Kamloopss, ranges between 30 and 50 i n c i n the Columbia. Mountains, and from 100 to 120 i n c i n t h e Coast Mountains  0  The average flow of a l l B,Cc rivers i s about 898,500 cfs Res  0  Confo  (BcGo  1964), which amounts to 651 000s,000 acre-feet or 33 in= 9  Nate  An-  other estimate of runoff i s the difference between annual precipitation (45 i n o ) and AE (15 i n c ) which i s 30 i n  0  The discrepancy of three inches  i s surprisingly small, considering the method of obtaining the estimates^  132 3. WATER NEEDS In 1956, 438,650 acre-feet of water were used to irrigate 200,440 acres of land i n British Columbia.  An estimated 400,000 acres were con-  sidered potentially irrigable, requiring an additional 1,025,000 acre-feet of water (B.C. Nat. Res. Conf. 1964).  The breakdown of irrigated and  potentially irrigable land i s presented i n Table 4.  In 19&5, more than  300,000 acres were irrigated and licenced water use was 769,100 acre-feet (B.C. Water Res. Serv. I966).  I t appears that between 195^ and 1965,  100,000 acres of the potentially irrigable land had become irrigated land. In 1965, then, 300,000 acres were being irrigated and 300,000 additional acres were potentially irrigable, suggesting that the present licenced water use for irrigation of 769,100 acre-feet would l i k e l y double i f a l l potentially irrigable land were developed.  Table 4 indicates a total water  requirement for irrigated and potentially irrigable land of 1,463,650 acrefeet. The annual runoff from B.C. rivers i s 651,000,000 acre-feet, so that i t appears that the province has adequate water not only for a l l potential irrigation requirements but for other potential uses.  Not a l l the water i s  economically available for irrigation, however. Many of the major rivers are so deeply entrenched that their water requires too great a pumping l i f t to economically supply adjacent irrigable land.  Because of this, l i t t l e  use has been made of major streams i n British Columbia for irrigation.  On  the other hand, small streams are commonly used to irrigate nearby land, many such streams being so fully utilized for irrigation that water rarely  133  Table  4.  Irrigated  and p o t e n t i a l l y i r r i g a b l e l a n d i n  and  requirements (from  water  Tables  3  British  Columbia,  Nat. Res. Conf. 1964,  and 4)  Irrigated Area  Region  B.C.  i n  acres  land, Water in  195^  Potentially  use  Area  acre-  in  acres  irrigable Water in  land  required  acre-feet  feet  Total requirement  i n  acre-feet  Kootenay  13,720  31,000  120,000  360,000  391,000  West Kootenay  12,130  15,160  75,000  150,000  165,160  70,400  193,600  100,000  300,000  493,600  5,210  5,210  10,000  10,000  15,210  4,280  4,280  15,000  15,000  19,280  Kamloops-Lillooet  77,300  154,600  60,000  150,000  304,600  Central  17,400  34,800  20,000  40,000  200,440  438,650  400,000  1,025,000  East  Okanagan, kameen,  SimilKettle  Valley Lower  Mainland  Vancouver  Island  B.C.  Total  74,800  1,463,650  134 flows i n these streams below the irrigation intakes.  There are about 600  dams on these streams under licence to store spring freshet and other water in excess of irrigation requirements  (BoC  0  Nat. Res. Conf. 1964).  The following l i s t of the major licenced water uses indicates the requirements of these uses i n relation to one another. The l i s t i s derived from an analysis as of April, 1965, presented by the B.C.  Water Res. Serv.  (1966). Domestic 13,664 acre-feet/year Irrigation 769,100 " " " Industrial 1,381,965 " " »' Processing ore 670 " " " Power - 156,755,412 " »' " Waterworks 534,719 »' " ••'. There has been some apprehension that development of B.C.'s hydro power will result i n most of the province's water being appropriated for that purpose (B.C. needs.  Nat. Res. Conf. 1964), leaving l i t t l e for future irrigation  In view of the very small percentage of the total water resource  that w i l l be required for any foreseeable consumptive use (e.g., irrigation), such fears seem groundless. Those water licences that have been issued for the  Peace and Columbia River projects have included a clause to the effect  that the licencee's rights shall be considered subsequent to any rights granted under any licences that may be granted, at any time, for the consumptive use of water.  Consumptive use i n this case includes domestic,  municipal, stock-water, irrigation, mining, and industrial use.  The clause  establishes a permanent priority for these uses over power use i n these major river developments (B.C. Nat. Res. Conf. 1964).  135  h-. WATERSHED  MANAGEMENT  REGIONS  Ideally, the province should be divided into watershed-management regions, within which the problems of watershed management would be similarc However, few areas of the province have unique problems and the degree of any problem varies l i t t l e across the province?  Several regions may be  delineated on the basis of water scarcity, flood and erosion control? Coastal Region Irrigation i s not needed for crops i n the Coastal region (except in the south-west of the province, e go, Fraser Valley and Saanich), 0  and the rivers do not supply water to other regions creasing the water supply i s not necessaryc directed to reducing peak flows ing  u  Therefore, in-  Forest management should be  and minimizing erosion, and at maintain-  spawning habitat for anadromous fish where these are of importance.  Peace River Region The Peace River region of British Columbia does not require irrigation for agricultural crops ( B C - Nat. Res= Confc 1964), industrial, water ;  needs are limited;, and the rivers of very l i t t l e water demando  f l o w  to the Arctic Ocean through  an  area  Therefore^ i n this region,, watershed manage-  ment should be directed to reducing peak flows and minimizing erosionColumbia Mountain Region The Columbia W.;yuivtain region i s similar to the previous two regions i n that the  A n n u a l  moisture deficit i s zero.-  This region  includes only  a small area at the higher elevations of this range o f mountains. The  136 rivers rising i n the region do flow through areas of moisture deficit as well as areas i n which there are water uses other than irrigation;  There-  fore, forest management should be directed not only to flood and erosion control,, but also to increasing water supplieso Interior Region The Be Go Interior from the southern to the northern boundary of the province has an annual moisture deficit,, but the deficit i s much greater i n the south where farming i s much more importantc  One objective of  forest management having high priority i n the Southern Interior should be increasing water siipplies and prolonging spring runoffo  Erosion and  flood control should receive considerable attention i n forest management as wellc  5o  WATER DIVERSION SCHEMES  In the early 1960 s a proposal to divert Canadian waters to the !  United States, called the North American Water and Power Alliance, or the NAWAPAj. was put forth by the Ralph Mc Parsons Company, an engineering firm of Los Angeleso  The proposal touched off a lively debate on Canadian  water policy^ mostly by elected representatives of federal and provincial governmentso The timing of the NAWAPA proposal was termed unfortunate by the British Columbia Minister of Lands,, Forests and Water Resources because 2  of the danger of formulating water diversion policy without adequate i n formation (Williston 1966)0  Howeverj from this standpoint the proposal  137 was worthwhile i n that Canada's water resources began to receive muchneeded attention, inventory of the resource and prediction of national needs being foremost among the suggestions. Other diversion schemes have been proposed i n recent years to make water available to water-short areas of Canada and even to international waters (e.g., the Great Lakes), but none have proposed diversion to the United States, nor have been of the size of NAWAPA. This section will describe some of these diversion schemes, their relation to the water resources of British Columbia, and their implications with respect to a national water policy. NAWAPA According to i t s planners, the North American Water and Power Alliance will provide direct benefit to seven Canadian provinces, 33 American states, and three Mexican states, and the beneficial economic effects of the scheme will be f e l t by the whole continent.  I t has been estimated that the U.S.  national income from agriculture, livestock, mining and manufacturing would increase by $30 b i l l i o n annually (Moore 1965).  The project would add  $2 b i l l i o n per year to the B.C. economy (Vancouver Sun 1965c). NAWAPA would generate i t s own power for pumping and would have a saleable excess.  I t would provide a navigable waterway from Vancouver to  Lake Superior, deliver irrigation water to the northern plains from Alberta to South Dakota, and would increase flow through the Great Lakes-St. Lawrence system. The project would provide storage for 4.3 b i l l i o n acrefeet of water, 2.8 of which would be i n Canada.  I t would irrigate 36  138 million acres, nine million i n Canada, six million i n Mexico, and 20 million i n United States.  An installed capacity of 99?700 kilowatt-hours of  electric power would be part of the scheme, 569000 of which would be i n Canada (U S 0  0  Senate 1964).  The NAWAPA project would cost about $80 billion of which construction i n Canada would account for $31 b i l l i o n , and Mexico $2 b i l l i o n  9  and i t would  take about 30 years to complete (UoS. Senate 1964). Location.  The project would begin i n the headwaters of the Yukon  River i n the Yukon and the Tanana River i n Alaska^ where reservoirs would be created by a series of dams.  From here, water would be pumped 300 feet  to the Peace River reservoir. Several streams i n northern British Columbia would be dammed to form a chain of reservoirs above the Peace River reservoir.  A portion of the outflow from the Peace River reservoir would be  directed into the Alberta-Great Lakes canal.  Diverted flows from several  streams on the east slopes of the Rockies would be added to this system also, providing inflow to Lake Superior i n excess of 40 million acre-feet per year.  A diversion from the South Saskatchewan River i n Saskatchewan  would take water into the plains states of United States. By damming the Columbia Frassr and Kootenay rivers 9  9  s  which have  their upper reaches i n the Rocky Mountain trench, a 500-mile-long reservoir would be created 3»000 feet above sea l e v e l Montana.  9  extending southward into,  The annual yield into the trench would average 74 million acre-  feet and would provide the major supply for the NAWAPA system (C.A.A.E. 1966, Can. Coun. Res. Ministers 1964, U.S. Senate 1964).  139  Conception.,  In March, 1964, the Parson's Plan, or NAWAPA, was re-  leased for public examination and appraisals  According to A.W  0  Moore,  vice-president of the Ralph Mo Parsons Company^ the concept was brought to the attention of the company by i t s foreign operations division which has been engaged i n water development projects i n Taiwan, India, Iran, and Kuwait.  I t was this knowledge of water and mankind's needs for water which  led the company to begin development of the project (Moore 1965)* Other reasons for the development of the plan have been given which do not attribute such an altruistic motive to the Parson company. One i s that the firm, "looking far into the future when i t s current heavy missile program for the U„S. government i s phased out, conceived of the North American Water and Power Alliance" (CoA.A.E. I966, p. 23). A similar view i s that the scheme i s nothing more than an attempt by "a private engineering firm, to drum up business for themselves" (McNaughton as quoted by MacDonald 1966, p. 6). Another reason i s that " i t s immediate objective appears to be o 0 . to s  maximize' the amount of engineering construction during the next 30 years, a period when the industry may be less active than i t has during the l a s t quarter century" (Lloyd 1966, p. 14). These are the views of some Canadians, and the plan has not been as strongly supported i n Canada as i n the United States where "acceptance of the concept by the general public, elected officials and the engineering profession has been heartening" according to a Parson's company vicepresident (Moore 1965> p» 30).  140 Perhaps there has been wide acceptance of the NAWAPA plan i n the United States, although no government agency has yet commissioned any technical study of the project.  The U.S. government has not acted on a  congressional resolution to refer the project to the International Joint Commission for study (McNaughton, as quoted by MacDonald  1966).  The  reason that the study has not been referred to the commission may be that the plan does not have the support of the U.S. government. I t may also be that because a joint reference by both the U.S. and Canadian governments to the commission i s required, the U.S. government has refrained, recognizing that Canada has vetoed past attempts at international study of a purely Canadian resource.  In 1964, Canada turned down the sug-  gestion by the U.S. State Department that a study be made of regulating Great Lakes water levels by partial diversions from rivers i n northern 1  Ontario and Quebec (O'Leary I966). The NAWAPA project has been studied by the Western Water Development subcommittee of the U.S. Senate Committee on Public Works.  Some of i t s  views are expressed i n the following section. Engineering.  The NAWAPA project has been studied by a U.S. Senate  subcommittee and some of i t s shortcomings have been pointed out i n the committee report (U.S. Senate 1964, p. 1-2): I t i s not an engineering study, i t i s not definitive in the sense of location, i n the height of dams, or i n the water impoundments. Nor are i t s water availability figures or hydropower projects definitive.  141 But i t does apply hydrologic and engineering standards to the concept. And i t was a serious enough attempt to warrant a serious analysis. Lloyd (1966, p. 14), a geography professor at McGill University, described the project as an "exercise i n sophomore c i v i l engineering which has received far greater attention than i t ever deserved." plan includes a seaway to James Bay where " . . .  The NAWAPA  the off-shore waters are  so shallow that even a canoe cannot be assured of getting within sight of land at low tide" (Lloyd 1966, p. 14). The federal Water Resources Branch studied NAWAPA i n I965 and concluded that there was a lack of definite information on engineering problems and costs.  From the Canadian viewpoint there are closer and more  economic sources of water for the Canadian prairies than the NAWAPA-proposed trans-Canada canal (O'Leary I966). National water policy.  The engineering and economic feasibility of  NAWAPA i s not the main consideration at this point in the development of Canada's water resources.  Presumably these aspects would be proven before  any commitments were made. One important factor i s the economic feasib i l i t y of Canada's participation i n the project, i.e., the relation of the benefits and costs accruing to Canada.  But the most important factor from  the Canadian standpoint i s the long-term effect of water export on the welfare of the nation.  Will water export limit industrialization?  water export doom particular regions to future water shortages?  Will  And, i f  so, what are the implications? When NAWAPA f i r s t became a popular topic some of the views expressed by Canadian elected representatives were quite extreme, but gradually these  have moderated.  I n the beginning, Canadian views were, generally, that no  diversion to the United States should be permitted.  Since that time the  benefits which could accrue to Canada from water export have been considered, the r e s u l t being a more t o l e r a n t attitude toward such export. A no-diversion p o l i c y was held by Diefenbaker, leader of the Progressive Conservative party i n the federal House o f Commons (Vancouver Sun  1965a).  Hamilton, a Progressive Conservative member of the House o f  Commons, held that Canada should consider water export provided the country benefits i n such ways as guaranteed access to U.S. markets f o r s t e e l and wood products, along with t a r i f f reductions (Vancouver Sun  1965b).  Prime Minister Pearson stated that export o f water would be benef i c i a l to Canada as long as only that amount would be diverted which was surplus to Canada's future needs.(Vancouver Sun  1965a).  minister o f Northern A f f a i r s and National Resources, water to the United States was not negotiable. going to keep i t " (Vancouver Sun  1965a).  Laing, federal  said that d i v e r s i o n of  " I t i s our water and we're  I n January,  1966,  Laing's views  were that Canada's water was not negotiable u n t i l i t had been surveyed and the nation's needs provided f o r (O'Leary  I966).  Laing's executive assistant,  Austin, said that the L i b e r a l s do not agree with sharing Canadian water (Vancouver Sun  1965a).  The views i n the previous two paragraphs are those o f p o l i t i c i a n s who expressed t h e i r views i n the heat o f an e l e c t i o n campaign.  The lack o f  agreement on a water-export p o l i c y within either of the two p o l i t i c a l parties i s i n d i c a t i v e o f how meaningful e l e c t i o n speeches are.  I t i s also i n d i c a t i v e  of how l i t t l e thought had been given to a national water p o l i c y u n t i l then.  143  McNaughton, former chairman o f the Canadian section of the International J o i n t Commission, stated that there must be no sale o f water to the United States i n the foreseeable future (C.A.A.E. did  1966),  although he  allow that diversion could be considered a f t e r studies have been c a r r i e d  out (MacDonald  1966),  This view was also held by New, o f the Canadian  Natural Resources Council, who urged the formation o f a Canadian committee on water, weather, and vegetation, to carry out studies amounting to an inventory of resources  and a forecast o f needs (MacDonald  1966),  The l o c a l view on water export has been expressed by B.C.'s premier Bennet and Yukon commissioner Cameron who are opposed to NAWAPA (MacAlpine 1965).  W i l l i s t o n , minister of Lands, Forests, and Water Resources f o r  B r i t i s h Columbia, said that any p o l i c y at this time would have to be a p o l i c y o f no diversion, although he indicated that future p o l i c y would have to be the r e s u l t o f study (C,A,A,E, I 9 6 6 ) ,  Paget, deputy-minister  o f B.C.'s  Water Resources, stated that B r i t i s h Columbia has a huge water resource, but needs to reserve a l l o f i t f o r p o t e n t i a l development (MacAlpine 1965)* The majority of opinions stated by Canadian government o f f i c i a l s towards NAWAPA, o r to any diversion o f Canadian water to the United  States,  seems to be that the f i r s t requirement i s to make c e r t a i n that enough water to s a t i s f y Canada's future needs i s safeguarded. After that has been seen to,  diversion schemes may be considered.  This view was stated by Moss,  chairman o f the U.S. Senate committee studying NAWAPA (MacDonald 1966), and by McFarland o f the Ralph M. Parsons Company (Vancouver Sun The view that Canada must f i r s t study i t s resources  1965c),  and needs  before entertaining any plan to export water has resulted i n demands f o r  144 a national water policy (C.A.A.E. 1966,  Lloyd 1966).  Williston (1966) said  that i t might seem inconceivable for Canada to be without a national water policy, but i t may be impossible to state such a policy because of the differences i n the value of water between regions.  He said that federal-  provincial relations at this time are such that an over-riding  federal  authority affecting provincially-controlled water rights would not be readily accepted. Laing, then minister of Northern Affairs and National Resources, said that the federal government, while taking steps to see that Canada's national interest i s protected i n the development of water resources, does not intend to infringe on provincial ownership and responsibility (MacAlpine  1965). McNaughton, i n calling for a national water policy, recognized that i t would require an unusual degree of federal-provincial cooperation, but that federal guidance and coordination are essential (C.A.A.E. I966). The d i f f i c u l t y of resolving the problem of federal-provincial relationships and producing a national policy to guide development of Canada's water resource i s apparent.  The statements by both federal and  provincial o f f i c i a l s do not suggest that a national water policy i s imminent. However, the question of what Canada's policy toward water export should be, i s a valid one.  The following are alternatives;  (1)  No water export at any time.  (2)  Water export only after a study of the resource and forecasts of Canada's needs.  145 (3)  Water export even before any study has been made.  There are several reasons why a no-export water policy may be established.  One i s the belief that water i s unique  9  a national heritage  which should ba reserved solely for the use of Canadians,,  Another reason-  i s the desire not to export the raw material to sustain industry outside Canada*  Tied i n with this i s the view that by refusing to export water  9  industry w i l l have to come to the watero As for the f i r s t reason  9  water i s not unique as a resource but can  ba considered as a combination stock and flow resources  I t i s a stock  resource i n lakes and aquifers^ which can be depleted l i k e an ore deposit. I t i s a flow resource as part of the hydrologic cycle and renewable l i k e the forest.  Therefore water should be treated like other natural resourees  9  as part of the nation"s capital. The second reason has some v a l i d i t y very slow growth.  9  but would at best result i n 9  9  But water i s only one of the requirements of particular  industries^ and the attraction of water may not be enough to outweigh the advantages of other regions. i f i t had exported the water.  The water-rich area may be no better off than In f a c t  9  selling the resource would have  provided capital for the growth of the region. Export of water only after inventory of the resource and forecast of future Canadian needs i s probably the policy which would be most popular i n Canada.  But even this i s not necessarily the best choiceo  Why should only  that amount of water be exported that i s surplus to Canada's needs? I f the return from exported water i s greater than i t s value l o c a l l y  9  i t may  146 be advantageous to forego local use i n favour of the revenue from sale of the resourceo Considering the preceding paragraph the best policy might be to begin exporting water now or at least as soon as the engineering can be completed 9  for the diversion.  Canada could then take advantage of the revenue brought  i n by that part of the resource not presently being used i n Canada, and not l i k e l y to be completely used at any time i n the future. The problem i s that at this stage i n Canada's water resource development information i s lacking on both the extent of the resources, i t s present and probable future use, and i t s value to the nation.  Therefore i t would be  pure chance i f the export of a specific amount of water based on the present state of knowledge of the resource proved to be optimum from the standpoint of the future welfare of the country. Another factor i s that any export of water becomes an export i n perpetuity.  The supply cannot be decreased easily i f later i t i s decided  that Canada needs to retain more. I t has been pointed out by both Canadians and Americans that once water i s diverted into the United States, regardless of stipulations about Canada's future needs, the water i s not, i n fact  9  raclaimable (MacDonald 1966)0 Other Diversion Schemes Kootenai River diversion.  The Saskatchewan Power Commission proposed  that water from the Kootenai River be pumped through the Crowsnest Pass to the Old Man River, and water from the Columbia River be diverted over the mountains into the Bow River near Banff.  The Old Man and Bow rivers feed  147 the  South  and  Saskatchewan,  River  be  Lesser  Saskatchewan  southern  Columbia  the  Nothing anything  (Can.  on  River  has  l i k e l y  southerly  Peace  of  the  Kootenai  but  i t  has  focused  The  provinces  a  the  Saskatchewan-Nelson  three  of  provinces, of  the  northern  end  Lake  Winnipeg  northeast  to  Clearwater-Red the  Alberta  Clearwater and western affect  any  Water River  tains  east  of  River  from  the  via  the  Red  the  the  River  would  service  occur  future  diversion on  Saskatchewan,  River  basin.  i n and  use  British where  of  that  water  nor  needs  is of  and M a n i t o b a have  east  and  scheme,  the  This  flowing  diversion.  department  is  Deer  for  (Can.  B.C.-Alberta  River  Counc.  the  basin from  i s  the  begun  within  Alberta  Nelson  -  the  River  A project  the  Res.  border.  Saskatchewan  River.  via  the  into  draining  the  Lake  Bay.  Columbia r i v e r  North  Deer  Red  to  Peace  the  rivers  especially  affect  attention  Manitoba,  Saskatchewan British  River  Winnipeg,  Resources to  would  River  Deer  from  1964).  discussion,  Saskatchewan  Hudson  Saskatchewan  Alberta  Columbia.  Alberta,  i n  of  water  Qu"Appelle Valley,  Min.  River  come  prairies. study  provinces  Columbia diversions  British  of  North  considerable and  the  Res.  the  proposed that  the  i n  to,  across  and  via  Counc.  Kootenai  Peace  flows  Athabasca  created  diversions  the  the  then  proposal  where  downstream of  Lake,  which  Commission f u r t h e r  into  Saskatchewan  This  part  The  diverted  Slave  River  diversion  irrigation  to  plan the  of  i n  1964).  Min.  Clearwater The  being considered  South  to  eastern This  River  i s  water  in the  Saskatchewan  the  Alberta  scheme  rises  divert  from  by  does  the  not  moun-  Clearwater Rivers,  148  The or  GRAND,  the  GRAND c a n a l . canal,  Harricanaw  Bay,  into  the  (Canadian  River,  a  sidered levels to  of  the  and  It  would  feasible.  Quebec  was  that  through also  running  Kierans,  by  length  committee  revived  T.W.  was  of  f e a s i b i l i t y  the  federal  studies  be  Quebec  the  and  but  to  i t  Great  was  River House  not  Lakes'  out  James  lock-  the  government  carried  divert  into  Ottawa  described  i960,  in  and  Development, would  dredging  d i s c u s s i o n on  and  Northern  Ontario  scheme  During  and  create  the  The  and water  plan  engineer,  flows  i960).  Commons  forests,  1964,  Ontario  now  Lakes.  economically i n  which  Replenishment  Sudbury  shipping route  House  Commons m i n e s ,  Great  p r o p o s e d by  Great  construction,  The  of  con-  water  proposed  (Can.  Counc.  R e s . M i n . 1964). The i t  GRAND c a n a l  indicates  that  water  problems  Great  Lakes  water  is  Lake  part  The  to  be  use,  and  be  the  United  flush  i t s  waste  the  value  established  be  diversion  on  soon  to  a  of  and to  the  guide  British  American,  and  e.g.,  as  some  of  Chicago  the  from  this  discussion of  resource  that  of  the  to  quickly use  so of  whatever  nation. that  this  a  the  Mississippi  resource,  the  solutions  uses  into  i s  Columbia  implication  water  study  Canada's  of  considered  A further  States,  drawn  completed  waters  being  also.  schemes  thorough  the  are  part  into  based  undertaken  affect  Canada,  Canadian,  conclusion  interprovincial  not  diversions  eastern  diverted  Michigan  must  river  in  are  does  policy i t s  national  resource.  to  that  Great water  River  the  Lakes from  system.  international i s  adopted  present  This  i s  but  study water  and must  and  i t  future be  policy  may  149 CHAPTER Vc  FOREST MANAGEMENT AND THE WATER  RESOURCE IN BRITISH COLUMBIA Legislation dealing with water rights i n British Columbia cussed i n a previous section.  This chapter w i l l deal with watershed man-  agement i n British Columbia with regard to erosion and water yield, timing, and quality, 1,  WATERSHED MANAGEMENT AND LEGISLATION  Establishing the Forest Service The forest lands of British Columbia were administered from 1871 to 1908 by the Chief Commissioner of Lands and Works, and from 1908 to 1912 by the Chief Commissioner of Lands,  During this period, forest adminis-  tration was under three independent branches (Griffith 1965)? (1)  Timber Inspection Branch, responsible for the collection of royalties and other dues, as well as the control of trespass,  (2)  Scaling Branch, responsible for the scaling of timber cut,  (3)  forest Protection Branch, responsible for the protection of forests from f i r e . In 1910, the final report of the Royal Commission of Inquiry on  timber and forestry i n British Columbia was published.  I t recommended the  enactment of a forestry b i l l to create a department of forests to be headed by a chief forester. The duties of the chief forester would include direction of the department i n the care and maintenance of forest cover and the prevention of soil erosion (Fulton et a l , 1910),  150 In ing  the  early  Forest  Forest  Forest  " i n  mountain floods,  i n  slopes,  -  of  was  the  H.R.  Forest  passed  the  MacMillan  Branch  Forest  as  along  Act  Chief  the  establish-  Forester.  lines  of  dependence  of  the  ByUnited  completed.  f i r e  only  for  depend upon cover  a  spongy  the  flow  commissioners forest  main  from  of  of  those  water  catastrophes The also,  of  as  land  the  B.C.  has  and  the  as  also snow  well for  held of  They  all  was  water  supply  p.  1910,  altitude of  al.  i n  the  view  the  of  that  sheds  inviolate  protection not  erosion  and  soil  p.  B66).  others  about  been  establishing  placed  over  our  larger  streams  for  a l l  time.  .  reserves  over  bought  1910,  of  of  forest all  matter  p.  the  back 18).  has  world, again  one  forests,  1910,  s h o u l d be  and  D66).  consideration the  the  the  attests:  creating have  upon  the  suggested by  reserves  (Sutton  et  power,  back  al.  prevention  (Fulton  cover  s h o u l d be  high  or  holds  expressed  as  governments  areas  of  future  and  governments  forests  dilatory water  et  irrigation  forest  snow  of  "the  for of  storage  the  quotation  cover  the  (Fulton  reserves  very  reserves  the  slides"  Extensive  for  up  headwaters.  or  large  into  for  with  grounds  question  holds  department  necessity  either  maintenance  rivers"  forest  been  forest  cases  created  on  following  gathering  many  and of  the  burning  but  reserves.  imperative  s o i l  reserves,  creation  forest  the  supply  by  that  of  water,  the  agreed  reserves  duties  recognized the  1910  C o l u m b i a on  the  sustaining  permanent  time,  appointed  Commission of  w i l l  regulation  the  and  British  turn  The  of  Service  Royal  development  the  Branch,  legislature  Reserves The  which  provincial  organization  1913»  States  the  1912,  to  .  .  been and be  The a in  that  151 The an  strong  extreme  which  was  pressed only the  view  this  rapid  reason  "for  need  During  the  forty  for  their  The  Forest  thereon, In  forest of  not  for  of  1913)  area was  a  brief  of  f i r s t  was said  Act  of  the  hydrologic  time,  also  Sutton that  higher  that  of  for  i t s  establishing the  some  (1910,  the  extent  cycle,  forest  and  the  P«  a  on view  18)  ex-  covering  not  r a i n f a l l  Sutton  and  checks  forest  expressed  protection  beginning i n  history  watershed  to  levels.,"  reserves  following  a  increases  Commission report  review  of of  Chief  the  of  forest was  of  water-  the  1912,  reserves  protection  one  timber  of  water  watershed  MacMillan  year  later,  i n  or  creation which  supply"  and  Forest  provincial  reserves  not  the  protection  MacMillan  in  main  of  to  Lands  Columbia Gazette  the  River  suitable  protection  ( B . C  only  for  Depto  of  Forest  growing of  may  B.C.  Lands  grow  (B.C.  1915)°  Dept.  against  31,  establishment  Reserve.  timber  of  reserves  On December the  p.  1912,  forest  safeguard  1914).  Valley  of  reserves  establishment  that  British Elk  forest  streamflow  stated  (B.C.  Dept.  the  of  of  hereafter  (Prov.  advocated  existed  the  being  the  the  legislation  reserve, as  the  for  areas  appeared forest  growing  needed  because  for  timber  Forester  where but  provided  1912  protection  described of  but  forest  years  based  establishment.  necessary  notice  the  the  1913,  alienation 1914,  for  that  to  was  recognized  the  Royal  policy  maintenance  reserves  Lands  were  the  the  However,  about  from  Columbia indicates  the  90).  of  reserves  forests  now w e l l  water  on  forests. British  i s  of  evaporation,  of  a  forest  prevalent  lessens  maintained  for  relation  "It  authors  views  Branch  the  view:  descent  The  sheds.  of  especially  greatly  their  feeling  and  The nothing  152 In 1922. four forest reserves were established, covering 1,200,000 acres of the higher elevations of the Okanagan Lake watershed.  These were  the Okanagan Reserve on the west side of the lake, and Aberdeen Mountain, Grizzly H i l l s , and L i t t l e White Mountain Reserves on the east side (Griffith, undated). The Inkaneep Forest Reserve in the south-east section of the Okanagan Valley was established i n 1923•to serve a double purpose "since i t i s covered not only with a valuable stand of young timber which w i l l be of future commercial value, but also covers the headwaters of Vaseau, Sawmill, and Inkaneep Creeks, and the conservation of the timber on the reserve i s essential for regulating the streamflow therein" (B.C. Dept. of Lands 1924, p. 1 9 ) .  In the same annual report, i t was f e l t necessary to  define "reserve". I t might be well here to reiterate that the word 'reserve" may create a wrong impression. There i s no idea of locking these areas up and withholding them from use, but rather the proclamation dedicates them to the purpose for which they are best suited - timber production - with which may be coupled as protection, prevention of floods, game, and aesthetic purposes (B.C. Dept. of Lands 1924, p. 1 9 ) . In the period 1924-1929, 13 new forest reserves, or provincial forests as they were called after 1924, were established.  In 1930» 14  national forests were transferred to the provinoe (Griffith, undated). Two of these, the Arrowstone Forest and the Hat Creek Forest had been reserved by the dominion government for watershed protection but the province questioned their value as provincial forests. Of Arrowstone, the 1933 annual report of the Department of Lands stated, " i t i s doubtful i f  153  i t i s worth the expense of administration as a Provincial  Forestc,"  and  of Hat Creek Forest, " i t i s doubtful i f this object [watershed protection] justifies i t s continued administration as a Provincial Forest"  (BoCo  Dept.  of Lands 1934, p, 7 ) , In 1934, the Arrowstone and Hat Creek Forests were cancelled, "having been found to be of l i t t l e value for the protection of commercial timber"  (B Cc 0  Dept, of Lands 1935* P°  Other provincial  forests were established after 1930» however, and by 1949$ 52 had been reserved. The point of this brief discussion of the history of forest reserves i n British Columbia i s that at no time was watershed protection the main consideration; i n fact i t appears as i f i t were a very minor consideration. Ease of administration of the timber resource seems to have been the prime reason for the establishment of forest reserves and provincial forests. The Royal Commission of  1955-1956  The terras of reference of the 1955 Royal Commission relating to the forest resources of British Columbia included inquiry into "the maintenance of an adequate forest cover with a view to the regulation of moisture runoff and the maintenance of the levels of lakes and streams" (Sloan 195^» p, 2 ) ,  Sloan (1956, p, 7 2 1 ) commented that i n the 1956 inquiry, watershed  management "did not appear to loom as large as i t did i n 1944-45o"  Much  of what was written on watershed management i n his 1956 report was from the 1945 report i n which mention was made of the role of forest cover i n watershed protection.  154 given  Some  of  the  below  to  illustrate  recommendations of  how  such  to  concerning  how  the  may  particular  to  obtain  suggested  be  necessary  and  erosion  sustained-yield important, canopy.  the  He  following  cover  policy cut  and  .  .  must by .  L o g g i n g methods  A l l  and of  a  the  to  .  the  and  reduce  to  dictate.  the  enough  to  i s  lack  of  of  the  knowledge  the  for  are  value  of  direction  obvious. consumption by  In  some  water  cut  may  maintain  a  of  cases,  as  the  most  supply. be  stream-flow  section  nature  need  water  the  Where  The  However,  increase  anticipated,  report  1956  general  watershed.  Where  heavy  regulation  f a i r l y his  as  a  is  complete  report  of  with  forest the  723): of  these  research  be  and  determined  men e q u i p p e d  fundamentals  by  for  w i l l  experimentation a  this  close work  .  study by  .  .  .  of  training  . must  careful  these to  of  recommendations p.  his  nature.  knowledge  the  application  .  experience.  according  not  in  objectives.  removed  l i g h t  (1956,  conditions  ditions  be  considerable  Methods local  the  practical  necessitate  improve  be  Sloan  questionable  thinning  i s  by  view  necessary  would  must  statement  i s  may  damage  concluded  The  to  i n  watershed  the  that  made  non-specific  understandable  non-commercial  flood  their  recommendations  Sloan forest  i s  achieve  general  recommendations  also  be  appraisal  matters  governed of  by  local  conflicting  con-  values.  must,  however,  be  decided  circumstances  peculiar  to  the  area  under  review. The  recommendations  cluded  direction  b i l i t y  for  Commission  as  to  watershed inquiry  the  would  have  government  studies.  indicated  The that  been  agency  Forest its  of  greater which  Service  research  value  should  they  aocept  submission  division  i f  was  to  had  i n -  responsithe  prepared  Royal to  155 undertake  studies  However,  such  prepared  a  The  on  studies  set  of  section,  Service the  Concerning the  Forest  The  Forest  Water  Resources  erosion  studies,  conservation  (Sloan  carried  although  watershed  studies Res.  was  has  however,  protection  i n  assumed i n  1964  I965).  Serv.  Service  out,  As  p.  1956,  632).  British by  in  cases  this  agency  has  done  attitude  toward  watershed  Columbia.  the  indicated  d o c u m e n t e d many  (1963)  Stewart  B.C. a  of  l i t t l e  Water  preceding erosiono  more  than  Service.  Act  of  British  indication  tration  i n  the  reference  reserves  been  for  (B.C.  C o l u m b i a may  i n  not  erosion  British  passed  have  water  for  Water  Another  no  and  guidelines  responsibility  Resources  soil  soil  and  (Prov.  1912  of  the  found  province.  to  for  be  Columbia  of  maintenance  in  The  B.C.  water B.C. of  the  statutes  forest  act  conservation  timber  governing  forest  (Prov.  B.C.  whereas  referred  1912)  to  production  management  the  of the  adminismakes  1964)  f i r s t  in  forest  act  creation  of  forest  and p r o t e c t i o n  of  water  supplies. A Alberta  brief w i l l  forestry the  Serv.  1966,  serve  the  any  part  State  provide  laws  control  look  grant  For.  forestry  a  authority  to  s o i l  erosion"  p.  1).  Stipulation  the Serv.  ice,  or  public  laws  i n  comparison with  of  snow, of  at  on  water domain,  I966).  the  the  of  except  B.C.  made  lands that  irrigation as  United  forest  service  forest  also  any  western  forest  public is  the  no  to  act.  (Colo. trees  the  and  Colorado  "foster  d i s t r i c t  provided in  States  and  State needed  shall  be  statutes  promote  For. to cut  confrom  (Colo.  156 Forestry laws of the state of Idaho include in the preamble the statement that water resources are among the most important natural resources of the state, and that "forest cover i s a v i t a l factor i n regulating and conserving streamflow and water supply; forests are effective i n conserving s o i l , preventing i t s erosion and consequent s i l t i n g of stream channels and reservoirs" (State of Idaho 1964, p. 20).  Section 38-304 of the Idaho  forestry laws l i s t s general forest practices to guide logging of public and private lands within sustained-yield districts, in order to protect the site. Under Utah forestry laws, a board of forestry and f i r e control was established whose responsibilities included "protecting non-federal forest and watershed areas on conservation principles" (State of Utah 1961, p. 4). In California, the Forest Practice Act requires that private forest lands be managed according to forest practice rules established for each of four districts.  For the Redwood District, for example, section 914.8  sets out  regulations to control erosion, and deals with runoff from road surfaces as well as stream-bed crossings (State of California 1965)» Section five of the Forest Reserves Act of Alberta states that forest reserves have been created for the conservation of forests and other vegetation, and "for the maintenance of conditions favourable to an optimum water supply" (Prov. of Alberta 1957* P° 1792).  Section 10 auth-  orized the Lieutenant Governor i n Council to designate areas for the study, experimentation, and demonstration of watershed management (Prov. of Alberta 1957).  This act was repealed with the Forest Reserves Act of 1964  taking i t s place (Prov. of Alberta 1964).  However, the new act i s  157 substantially Of not  the  course,  necessarily  watershed  forest  as  a  indicate  l i m i t  rider  act  (Prov.  The  regulations as  he  the in  B C 0  provision  and of  i n  reference practice.  nature,  which  i n  advisable  been  no  or of  the  this  express  or  thereby i n  l i m i t i n g  Council  tends  of  regulations  licence  to  Kootenay dealing  example cut  crown  region with  making  i s  of  the  conditions  timber  British  watershed  i s  i n  laws  contained  act  does  practice  specific  Forest  for  act,  the  subsection  i n  An  a  forest  to  aspect generally  i n  the  B.C.  make  of  carrying  including partial  such  this  act out  matters  or  imperfect  made.  contained  the  to  s p i r i t  only  Lieutenant-Governor to  given  C o u n c i l may  necessary provisions  the  1537):  p.  with  Without  (2)  of  i n  actually  inconsistent  which  has  provisions  lack  Lieutenant-Governor not  purpose  does  1964,  0  management  consideration  following  considers  respect  watershed  consideration  the of  predecessor*  to  the  Nor  i t s  of  (1)  i t s  reference  protection.  necessarily contain  same  on  the  make .  .  Windermere These  (B.C.  the  of  power  .  the  ex-  . the  successful  Creek  watershed  include  Dept.  the  of  regulations  i m p o s e d on  Columbia.  protection  to  generality  (1),  the  Lands,  bidder of  the  following  Forests,  for East  conditions  Water  Resources  1964)s (1)  Logging out  (2)  of  and reach  Tractors away  road-building debris of  high  and l o g g i n g  from  the  banks,  shall  be  kept  out  of  streams  and  water. equipment except  for  shall the  be  kept  out  of  minimum number  streams of  and  necessary  crossings. (3)  No l o g g i n g  shall  take  place  within  two  chains  of  any  sink  a  hole.  158 The  above  conditions  protection  i n  British  ally  to  watershed  refer  watershed concern  management  with  conditions these  this  aimed  consideration  Columbia even  i n  the  forest  protecting  are  given  Also,  adhered to  How  serious  problem  i s  erosion  w i l l  be  British the  to  erosion  the  Park  on  l i t t l e , even  the the i f  though  the  fire  agency  and  Water has  of  i n  this i n  whose  found  minister,  Hope-Princeton any,  erosion  reforestation (B.C.  Nat.  erosion  Accelerated  recognized  this  due  Service  cited  as  of  erosion  has  l i t t l e  area"  not  as  an i n  been  not  the  general  degree  real  specific-  references  contracts  the  watershed  test  to  un-  contain to  of  which  the  problem i n in  British  Columbia.  fact,  i t  i s  a  Water  Resources,  in  charge  include given  a  erosion  no  deal  matter  of  thought  how  serious  Res.  Conf.  the  area  burned  He  and  great  studies,  Nat.  example 1945.  erosion  the  successful  stated  that  streams  of  apparent  i n  p.  1964, in  there  were  because  of  Manning had  running the  92).  been clear  severity  1964).  man's i s  a  (B.C.  h i l l s i d e s  Conf. to  the  and whether,  minister  forest  had  Res.  values,  responsibilities  the  omission of  to  chapter.  highway,  on  does  indicates  i s  given  EROSION  "remarkably a  act  timber-sale  enforced  province  Resources  the  i s  management.  deputy  denuding  deputy  However, Columbia.  is  considered  the  situation  Paget,  of  that  generally  Columbia's  provincial  stated  not  forest  probably  watershed  2.  Erosion  the  although  and  watershed  consideration  However, act  the  to  that though  protection.  problem. at  conditions  indicate  activity  l o c a l l y  i s  severe  and  may  be  British noted  by  casual  159 inspection  of  does  however,  seem  expected  s  from  The due  to  logged  the  f i l e s  logging  following  Examples  that  erosion  appearance of  and  the  or  of  Water  by i s  study not  of  as  severe,  some l o g g e d  Resources  roadbuilding.  Some  individual  generally,  as  It  would  be  areas.  Service of  watersheds.,  these  provide  examples  will  cited  be  of  in  erosion  the  sections.  of  Erosion  Brodie  Greek  flood.  The  following  example  is  from  a  report  by  of  the  Sloean  about  one-  (1965).  Pollard  Brodie Range  hillsides  into  Creek  the  half  square  shed  above  i s  Slocan  mile  i n  2,800  a  small  River,  stream  near  from  was  logged  ft.  Nelson.  1,500  area,  flowing  southwest  The  6,?00  to  1955  between  creek f t .  basin  is  elevation.  1964  and  out  The  to  a  14-inch  out  a  gravel  waterdiameter  l i m i t . In  A p r i l ,  depositing the  creek  years  ago  mud, as  boulders,  well  and  Brodie  1965,  as  and  trees  Creek  flooded,  brush  over  felled  power-line  clearing  moving dams.  It  that  f i n a l l y  through  broke There  was  appears  no  on  was  warm.  On  per  cent  of  the  logged  area.  not  unusual  for  the  time  the  of  p i l i n g  acre  of  channel were up  hayfield. during  floated  behind  and  Windfalls  logging  downstream  the  road  rain  day  after  Runoff year.  immediately  forming  obstructions  No  was  the  flood  from  floods  preceding snow  snowmelt, were  the  covered and  reported  the for  flood, about rate any  in  some  13, 1965°  appreciable  weather  the  1957*  i n  water  April  the  into  an  washing  and 20 was  other  160  stream  i n  the  SLocan  (I965)  Pollard the  flood  was  conveyed  via  occurred  on  Trees  and  unlogged Creek.  skid the  slope  forest the  as  trails  from  this  flood  damage  below.  apparent, that  the  report and  perhaps  flood  t r a i l s .  The  was  due  owner  of  deposited l a i d  a  settled  out  court  for  insurer  the  of  This the  evidence  claim but  was  for  the  of  be  made  the  provincial  The interesting  made  argument  to  put  (Leighton  by  of  40°  for  material  piled  up  and  debris  the  ever  been  dams  the  land  logging  just  the  s o i l .  f t .  way  on which company. from  The  the  was  logging  the  debris  The  claim  the  were  conclusion  via  the  Brodie  causing  trails  area  across  above  gave  skid  was  slide  upstream  of  to  A  from  slide  information  of  up  runoff  slope.  1,000  constructed.  reaching  spring  saturation  swath  leading  was skid  was was  insurance  adjusters  1966). that  to  the  insurers  refute.  court  communicated  not  hillside  cross-ditching  to  events  unnaturally-heavy  Finally  the  of  narrow  agricultural  suggest  reference with  had  according  out  a  water  no  against  strong  settled  rose,  runoff  (Leighton  too  reasons  to  claim  would  cut This  that  none  An  sequence  apparently,  material.  stated  the  unlogged  slide  level  behind  The  an  30°)•  (slope  time.  that  triggered,  impounded and  this  follows. to  the  creek  at  indicated  probably  earth  As  Valley  not  to  them  in  However, because  the  1966,  p.  by  writer  this  Department forth  of  the 1-2):  logging  Leighton  the  the A  company  (1966)  insurer  with  thesis.  of  the  was  stated  legally  stipulation  similar  considered that  l i a b l e ,  that  settlement  was  Highways.  insurer  to  support  its  stand  the  is  161 Those timber licences had been completely abandoned, not less than six months prior to the occurrence of the land s l i p . The land upon which the timber licenses rested had reverted to the total control of the Grown. o  o  .  .  .  e  o  «  .  .  e  .  o  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  I t was further argued i n the alternative that anything which our insured had done on the ground, was with the approval of the Forest Service, as well as being without negligence, insofar as road construction techniques were involved. I t was further argued, and this i s a principle of law, that even though our insured's road construction might have been the cause of moisture accumulation at any particular point, the likelihood that that moisture accumulation would produce a slide, was not foreseeable by our insured, so that our insured would not be liable therefore. Again, this i s based on a legal principle, we argued that even i f our insured should have foreseen the consequences of moisture accumulation so as to produce a slide, there was no reason to foresee that that slide would cause a blockage i n the creek, or alternatively that the creek would overcome that blockage and sweep down i t s valley to do damage to the Department of Highways and Mr. Plotnikoff. I t was argued that the damages of the claimant were too remote from the source of the commencement of the incident to be anything for which Pacific Logging could be liable. An interesting point i s the insurance company's claim that even i f the damage were the result of the logging, the logging company was not liable because (a) the timber licence had been abandoned six months before the land slip, and (b) whatever the company had done was with the approval of the Forest Service. I t would seem that, i f , by acts of commission or omission of the logging company, damage was incurred, the fact that the timber sale had been abandoned should have l i t t l e bearing on the case.  Regarding (b), approval  by the Forest Service i s usually required for the logging plan, including location of haul and main skid roads.  The intent i s certainly not to  assume responsibility for the action of the licensee, but a protective  162 clause i