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Impacts of agricultural drainage and an assessment of diffused aeration in the Serpentine River, British… Robinson, S. Thomas 1988

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IMPACTS OF AGRICULTURAL DRAINAGE AND AN ASSESSMENT OF DIFFUSED AERATION IN THE SERPENTINE RIVER. BRITISH COLUMBIA by S. THOMAS ROBINSON B.A.SC., University of British Columbia, 1986 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF APPLIED SCIENCE in FACULTY OF GRADUATE STUDIES Department of Civil Engineering We Accept this thesis as conforming to the required standard. THE UNIVERSITY OF BRITISH COLUMBIA OCTOBER 1988 ©Stanley Thomas Robinson, 1988 In presenting this thesis in partial fulfillment of the requirements for the advanced degree at the UNIVERSITY OF BRITISH COLUMBIA, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the Head of my Department or by his or her Representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Stanley Thomas Robinson Department of CIVIL ENGINEERING THE UNIVERSITY OF BRITISH COLUMBIA 2070 Wesbrook Place, Vancouver, Canada. V6T1W5 Date: October. 1988 ABSTRACT Urban expansion of the City of Vancouver has resulted in increased land development of the municipality of Surrey, and more intensive agriculture on the remaining farmland. From 1980 to 1984 five different fish kills in the Serpentine River attributed to low dissolved oxygen were thought to be caused by a combination of agricultural discharges, high autumn water temperatures, as well as rainfall and river flow patterns. In 1985 an experimental instream aeration system was installed in a lower reach of the river in an attempt to provide additional oxygen during the critical autumn period. This study was undertaken to determine the extent of the agricultural drainage discharge problem. Weekly sampling from July to December, 1987, revealed that organic pollutional loading from dairy farms was high. Nutrients loadings in the river supported a heavy algal growth which resulted in an oxygen deficit during autumn algal die-off and decay. Although the flushing of farm ditches normally exerts an additional oxygen demand on the river, this was not observed in 1987 because the major autumn rains began on Oct 30, and lower water temeratures prevented a rapid exertion of the biodegradable oxygen demand. Implementation of source control of farm animal wastes is strongly recommended, along with a program of public education on conservation and management of natural habitat. Harvesting of filamentous algae in the river may eventually prove necessary for successful rehabilitation as diffused river aeration appears to be having a very small effect. ii TABLE OF CONTENTS Page ABSTRACT ii TABLE OF CONTENTS iii LIST OF TABLES vi LIST OF FIGURES vii ACKNOWLEDGEMENTS x 1.0 INTRODUCTION 1 2.0 BACKGROUND 3 2.1 Brief History .3 2.2 Land Use in the Serpentine Watershed 4 2.3 Hydrology and Climate 7 2.4 Fish Resources and River Uses 10 3.0 IMPACT OF AGRICULTURAL DRAINAGE ON RECEIVING WATERS AND ARTIFICIAL AERATION IN RIVERS 12 3.1 Literature Review of Nonpoint Source Pollution 12 3.2 Literature Review of In-Stream Aeration and Water Quality Modeling 18 3.3 Past Research on Water Quality of the Serpentine River 20 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY 23 4.1 Introduction 23 4.2 Sampling Locations, Site Descriptions, and Flow Patterns 24 4.3 General Water Quality Methods 28 4.3.1 Dissolved Oxygen 28 4.3.2 Temperature 28 4.3.3 pH 28 4.3.4 Specific Conductance 30 iii 4.3.5 Chlorophyll-a 30 4.4 Methods Used to Assess Dairy Farm Drainage .30 4.4.1 Chemical Oxygen Demand 31 4.4.2 Total Organic Carbon 31 4.4.3 Total Ammonia/Ammonium 31 4.4.4 Nitrate/Nitrite Nitrogen 32 4.4.5 Organic Nitrogen 32 4.4.6 Ortho-Phosphate 32 4.4.7 Total Phosphorus 33 4.5 Methods Used to Assess Aerator Performance 33 4.5.1 HydrolabData 34 4.5.2 Depth Profiles of Dissolved Oxygen, Temperature, Conductivity 35 4.6 Additional Information Gathered 35 4.7 Statistical Correlations 36 5.0 RESULTS AND DISCUSSION 37 5.1 Analysis of Data 37 5.1.1 Water Quality of Serpentine River 37 5.1.1.1 Dissolved Oxygen 37 5.1.1.2 Temperature 53 5.1.1.3 pH 56 5.1.1.4 Specific Conductance 61 5.1.1.5 Total Organic Carbon and Chemical Oxygen Demand 63 5.1.1.6 Nitrogen 68 5.1.1.7 Phosphorus 74 5.1.2 Water Quality in Drainage Ditches and Latimer Creek 77 5.1.2.1 Dissolved Oxygen 77 5.1.2.2 Temperature 80 5.1.2.3 pH 83 5.1.2.4 Specific Conductance 83 5.1.2.5 Total Organic Carbon 83 5.1.2.6 Nitrogen 87 5.1.2.7 Phosphorus 92 5.2 Effects of Dairy Farm Drainage on Water Quality 95 5.3 Effect of Rainfall and Tidal Cycle on Water Levels and Water Quality 97 5.4 Assessment of Aeration System 100 5.4.1 Tidal Effect and Flow Pattern in the Aeration Zone 100 5.4.2 Discussion of Past Aerator Assessments 107 iv 5.4.3 Preventing Fish Kills 107 6.0 DISCUSSION OF SELECTIVE PAST WATER QUALITY FINDINGS 109 6.1 Phytoplankton Populations 109 6.2 Sediments 110 6.3 Low Dissolved Oxygen Levels and Rainfall 111 7.0 CONCLUSIONS AND RECOMMENDATIONS 113 7.1 Conclusions 113 7.1.1 General 113 7.1.1 Specific 114 7.2 Recommendations 116 REFERENCES 118 ADDITIONAL BIBLIOGRAPHY 122 APPENDIX I - Water Quality Data 124 v LIST OF TABLES Table Title Page 1. Toxicity of Total Ammonia to Fish 71 2. Ultimate Oxygen Demand for Serpentine River and Dairy Ditches 98 3. Water Levels for Serpentine River and Latimer Creek 99 4. Rainfall and Fish Kills 112 A-1. Water Quality Conditions for Site 176 125 A-2. Water Quality Conditions for Latimer U/S 126 A-3. Water Quality Conditions for Latimer D/S 127 A-4. Water Quality Conditions for Dairy Ditch 1 128 A-5. Water Quality Conditions for Harvie Rd Ditch 129 A-6. Water Quality Conditions for Site 80 130 A-7. Water Quality Conditions for Site FH 131 A-8. Water Quality Conditions for Site #10 132 A-9. Water Quality Conditions for Site 152 133 vi LIST OF FIGURES 1. Map of the Serpentine/Nicomekl Watersheds and Floodplain 5 2. Official Surrey Municipality Plan 6 3. Map of the Upper Serpentine River Showing it's Origins near Guildford and the Upper Floodplain 8 4. Map of the Serpentine River and it's Tributaries 9 5. Map Showing Sampling Sites on the Serpentine 25 6. Map Showing Sampling Sites for Dairy Ditches and for Latimer Creek 26 7. Map of the Lower Serpentine Floodplain, location of Aerator and Tidal Gates 29 8. Dissolved Oxygen Along Serpentine, Sites 176, FH, & 152 38 9. Dissolved Oxygen Saturation for Upper Serpentine, Sites 176, 80 & FH 39 10. Precipitation for the Upper Serpentine Watershed 40 11. Precipitation for the Lower Serpentine Watershed 41 12. Dissolved Oxygen Saturation for Lower Serpentine, Sites #10 & 152 43 13. Dissolved Oxygen/Depth Profile at Site #10 44 14. Dissolved Oxygen/Depth Profile for Site 152 45 15. Dissolved Oxygen Along Serpentine's Length, Sept 08,15, 22 46 16. Dissolved Oxygen Along Serpentine's Length, Oct 13, 27, Nov 10 47 17. Chlorophyll-a in Upper Serpentine, Sites 176, 80 & FH 48 18. Chlorophyll-a in Lower Serpentine, Sites #10 & 152 49 19. Dissolved Oxygen and Water Levels versus Time, Sept 21 and 22 51 20. Dissolved Oxygen and Water Levels vs Time, Sept 23 and 24 52 21. Dissolved Oxygen Variation for a 24 Hour Period, Site #10, Photosynthesis and Respiration 54 22. Temperature Along Serpentine Length, Sites 176, FH, and 152 55 vii 23. Temperature/Depth Profile for Site #10 57 24. Temperature/Depth Profile for Site 152 58 25. Mean Air Temperature on Sampling Days, Upper and Lower Serpentine 59 26. pH Along Serpentine Length, Sites 176, FH, & 152 60 27. Specific Conductance Along Serpentine Length, Sites 176, FH, & 152 62 28. Conductivity/Depth Profile at Site 152 64 29. Conductivity/Depth Profile at Site #10 65 30. Total Organic Carbon in Upper Serpentine, Sites 176, 80 & FH 66 31. Total Organic Carbon in Lower Serpentine, Sites #10 & 152 67 32. Total Ammonia Along Serpentine Length, Sites 176, FH, & 152 69 33. Total Nitrates Along Serpentine Length, Sites 176, FH, & 152 72 34. Organic Nitrogen Along Serpentine Length, Sites 176, FH, & 152 73 35. Total Nitrates, Organic Nitrogen, and Chlorophyll-a at Site 152 75 36. Ortho-phosphate Along Serpentine Length, Sites 176, FH, & 152 76 37. Total-Phosphorus Along Serpentine Length, Sites 176, FH, & 152 78 38. Dissolved Oxygen Saturation in Dairy Ditches and Latimer Creek 79 39. Chlorophyll-a Levels in Dairy Ditches 81 40. Temperatures in Dairy Ditches and Latimer Creek 82 41. pH in Dairy Ditches and Latimer Creek 84 42. Specific Conductance in Dairy Ditches 85 43. Total Organic Carbon in Dairy Ditches 86 44. Nitrogen Forms and Total Organic Carbon in Latimer Creek 88 45. Nitrogen Forms at Dairy Ditch 1 89 46. Nitrogen Forms at Harvie Rd Ditch 90 47. Total Ammonia on Latimer Creek, Latimer U/S & D/S of Dairy Ditch 1 91 48. Phosphorus Forms at Dairy Ditch 1 and Harvie Rd Ditch 93 49. Phosphorus Forms at Latimer Creek, Latimer U/S & D/S of Dairy Ditch 1 94 viii 50. Chlorophyll-a Concentration as a Direct Indication of Trophic Boundaries 96 51. Dissolved Oxygen and Water Levels vs Time, Oct 16 and 17 101 52. Dissolved Oxygen and Water Levels vs Time, Oct 18 and 19 102 53. Dissolved Oxygen and Water Levels vs Time, Oct 22 and 23 104 54. Dissolved Oxygen and Water Levels vs Time, Nov 21 and 22 105 55. Dissolved Oxygen and Water Levels vs Time, Nov 23 and 24 106 ix ACKNOWLEDGEMENTS The author would like to express his sincere thanks to Dr. Ken Hall, for his guidance throughout the research work. Dr. D.S. Mavinic was also instrumental in defining the scope of the project and in completing the manuscript. Brent Moore was of tremendous assistance in providing laboratory funds, gathering equipment, and in practical aspects. George Derkson assisted by gathering much of the 24 hour water quality data. Susan Liptak, Paula Parkinson, and Romy So contributed laboratory expertise. Financial support for laboratory analysis came from Region II, Waste Management Branch, Ministry of Environment, British Columbia. This thesis is dedicated to my wife, Jane. Her support and interest in this study was always an encouragement to me. x 1.0 INTRODUCTION Following the influx of settlers to the lower Fraser valley, many of the fish bearing streams which once drained the municipalities of Vancouver, Burnaby, Coquitlam and Port Coquitlam were destroyed, first by logging and farming, and then urbanization. The Serpentine and Nicomekl rivers, in the municipalities of Surrey and Langley, were historically productive but have become a casualty of conflicting objectives: drainage, intensive agriculture, and extensive urbanization. Negative impacts are being observed in populations of fish and other wildlife. Pollution inputs to these rivers from high density animal feedlots, crop fertilizers, and urban runoff have resulted in large algae blooms and severe eutrophication. Water quality deterioration of the Serpentine and Nicomekl Rivers was studied during the late 1970's by the Fish and Wildlife Branch and also the Environmental Protection Service. Five fish kills caused by low dissolved oxygen levels occurred between 1980-84 and led Region II, Waste Management Branch to initiate a number of research studies to diagnose the causes of the low oxygen conditions, and to prescribe corrective measures. Recommendations from the above research identified the need to reduce the nutrient and BOD loading of agricultural drainage and provide shade bearing trees in the floodplain. In the short term, however, it was deemed necessary to prevent future fish kills by in-stream aeration and/or algae harvesting. In 1985, a graduate student from the Environmental Engineering Group, Civil Engineering Department, University of British Columbia, designed and installed an diffused air aeration system in the lower Serpentine River. His sampling program raised new specific concerns regarding agricultural discharges in the river, but were not conclusive regarding the effectiveness of the aerator. As a follow-up to the work done by Town in 1985, the author undertook a sampling program that has attempted to: (1) assess the potential pollutional impact of 1 1.0 INTRODUCTION two dairy farms which drain into the upper Serpentine River, (2) re-examine the problem of nutrient enrichment leading to extensive algal blooms, and (3) assess the aerator's capabilities during a low oxygen event should one take place. 2 2.0 BACKGROUND 2.1 Brief History Improving the drainage of Serpentine/Nicomekl floodplain has until recently been the primary objective in the lowlands. The rivers were "intensively dredged and channelized to serve as drainage ditches for the surrounding farmland" (Bourque and Hebert, 1982). In addition, dykes were constructed along the banks, and natural trees and shrubs stripped and replaced with grasses. To secure fresh water for irrigation, tidal gates near the mouth of the rivers were built in 1912 to prevent ocean tides from entering the river. These activities allowed more intensive agriculture and gave flood protection to farmers. Even with these measures, however, the lowlands remain poorly drained; consequently there is little pressure to develop the floodplain for purposes other than agriculture. The soils in the floodplain are complexes of gleysols, mesisols, and humisols, which are low in pH and deficient in many minerals (Sprout and Kelley, 1961). Not surprisingly, fish and wildlife populations have suffered since the gradual destruction of their habitat began. Warm water temperatures are often above the lethal limits for trout and salmon during the summer. Many of the natural spawning and rearing areas in the Serpentine have been lost to erosion and siltation. Water quality on the Serpentine and Nicomekl Rivers became a concern during the 1970's, and several government departments began sampling programs. The Environmental Protection Service, after a study from June 1974 to November 1975, noticed that summer temperature and pH values were above the desired limits for fish (Bourque and Hebert, 1982). Cox and McFarlane (1978, BC Ministry of Environment, Water Investigations Branch) also collected river water chemistry data between 1974-77, as well as the Waste Management Branch between 1972-78. 3 2.0 BACKGROUND In October, 1980, there was a kill of 300-800 coho salmon in the Serpentine River, which prompted further water chemistry sampling by the Waste Management Branch. As recorded by Town (1986), recommendations by various levels of government were to reduce agricultural drainage contaminants, and provide shade bearing trees to reduce water temperatures. The occurrence of four more fish kills between 1981-84 rapidly increased the interest in artificial in-stream aeration, and by the summer of 1985 an experimental system was in place on the lower Serpentine for operation in the autumn, when dissolved oxygen levels are most likely to become critical and when the coho salmon begin their river migration. 2.2 Land Uses in the Serpentine Watershed The Serpentine River, with it's companion river, the Nicomekl, together drain a watershed of some 33,870 ha (Dick, 1975), and have a flood plain area of approximately 4,900 ha (Figure 1). The watershed's upland areas have traditionally been small farm acreages, however, these are rapidly giving way to an increasing amount of urban development. As the urban centre of Vancouver continues to expand into its suburbs, land use in the municipalities of Surrey and Langley shifts towards the industrial and residential sectors, and the productivity of agricultural land is increased by higher density farming. Market gardening on the flood plain is more intensive, and the number of animals on dairy farms grows, along with their forage needs. Surrey's Official Community Plan (Figure 2) outlines 27% of the municipality as commercial and urban residential, 12% as industrial, 27% suburban residential, and the remaining 31% as agricultural land (November 1986). Bourque and Hebert (1982) outlined the anticipated stresses that the Serpentine is likely to undergo as a result of urbanization : (1) flow regime changes - no water in summer due to excessive removal of groundwater in wells, and flooding in winter due to rapid runoff of paved surfaces; 4 Figure 1. Map of the Serpentine/Nicomekl Watersheds and Floodplain. (From Bergman, 1980) 2.0 BACKGROUND Figure 2. Surrey Official Community Plan Land Use Plan 6 2.0 BACKGROUND (2) channelization of upland tributaries; (3) vandalism of fish; (4) removal of stream bank vegetation and consequent increases in water temperature; (5) increased erosion and sedimentation; (6) sewage contamination of streams from septic tank leakage - resulting in in-creased nitrogen and phosphorus levels; (7) increased bacterial contamination from human and pet wastes; (8) toxic leachates from garbage disposals; (9) increased levels of oils, lead, pesticides and other contaminants in storm-water and road runoff. 2.3 Hydrology and Climate The Serpentine River originates at an elevation of 76 m near the Guildford area in urban Surrey (Figure 3). For its first 7.3 km the river flows southeast collecting small drainages from suburban acreages and through Tynehead Park with a slope averaging 1.0%. After reaching the floodplain, the river's velocity slows and it flows southwest for the remaining 22 km before emptying into Mud Bay. In the floodplain (where its average slope is only 0.015%) the river meanders through larger farms and receives its three major tributary streams, Latimer, Mahood, and Hyland Creeks (Figure 4). Latimer Creek originates in small upland acreages and then receives drainage from small farms as it flows through the floodplain. Mahood and Hyland Creeks originate in urban upland areas and flow through suburban areas to the floodplain. The Serpentine's tidal gates are located approximately 3.2 km from the mouth of the river and are meant to function as a one-way valve. They are passively opened towards the ocean whenever the river level becomes higher than the tide, and they are shut on a flooding tide to prevent salt water from entering the river channel. Although the gates are usually open from two to nine hours per day (Cox and McFarlane, 1978), in periods of dry weather when there is low drainage into the system, the gates can 7 2.0 BACKGROUND il Walter;.'-.'.'.. '•- .'.":':Hes UBMrg;ound ( ~ ~ Centir, - ]\ ' 1 : ' : Fraser". 1 6 ' Heights-: ; • Parki. '•'io B A R . . . ' , • . G e l t P o u l t . , ? ' * * " : C o ^ - . Cemetery •Poultry r F a r m ' Poultry 1 8 • -Farm Figure 3. Map of the Upper Serpentine River Showing it's Origins near Guildford and the Upper Floodplain. (From National Topographic Series, 1977) 8 Figure 4. Map of the Serpentine River and it's Tributaries. (From Bourque and Hebert, 1982) 2.0 BACKGROUND remain closed for up to 10 days at a time depending on the tidal cycle. Periods of long-term gate closures typically occur during the late summer and early fall. "Climate of the region is classified as modified maritime with overcast, wet, mild winters and drier, warm summers" (Bourque and Hebert, 1982). The average annual temperature range varies only 15 °C from 2 °C in January to 17 °C in July; this stability in temperature is a result of the Pacific Ocean's influence on weather patterns. Atmospheric Environment Services reports that summer daily maximum temperatures average 23 °C, whereas winter minumums are -1 °C. Annual precipitation averages 1200 mm in the lowlands, but is greater than 1400 mm in the headwaters of the streams. The bulk of the rain falls from October to May, with summer monthly rainfall near 40 mm. 2.4 Fish Resources and River Uses Prior to the influx of settlers in the Serpentine/ Nicomekl watershed, these rivers were productive habitat for many species of fish and waterfowl (Cox and McFarlane, 1978). Since that time, the fishery has declined due to agricultural and urban destruction of upland spawning and habitat areas in the river and its tributaries; intensive agricultural and land drainage practices in the floodplain have severely damaged fish rearing habitat. Some spawning gravel still exists in the Mahood, Hyland, and Latimer Creeks, and in a 3 km section of the mainstem in Tynehead Park (Schubert, 1982). Estimates on the spawning populations of coho salmon (Oncorhynchus kisutch) range from 1000 to 3500 from the 1950's to 1980. Backman and Rithaler (1987) estimate a total of 1200 coho spawned during the autumn of 1986. Although their present numbers are unknown, steelhead (Salmo gairdnerfl and cutthroat trout (Salmo clarki clarki) were once numerous. Additional species recorded in 1972 included: three-spined stickleback (Gasterosteus aculeatus). prickly sculpin (Cottus asper). redside shiner (Richardsonius bajteatus), lamprey (Lampetra 10 2.0 BACKGROUND richardsoni). brown bullhead (Ictalurus nebulosus). peamouth chub (Mylocheilus  caurinum). and crayfish and frogs (Bourque and Hebert, 1982). The river's main recreational value is angling. The autumn of 1987 marked the first year of operation for the Tynehead Salmon Hatchery, a Community operated Salmonid Enhancement Program. In addition, the whole Serpentine/Nicomekl floodplain remains an important area for migrating waterfowl and aquatic birds (Hirst and Easthope, 1981). 11 3.0 IMPACT OF AGRICULTURAL DRAINAGE ON RECEIVING WATERS AND ARTIFICIAL AERATION IN RIVERS Nonpoint sources of pollution have been widely reported in the literature and encompass several different sources: urban storm water runoff, agricultural drainage from cropland and from animal feedlots. This pollution encompasses sediments, nutrients, organic wastes from plants and animals, pesticides, salts, and pathogens. Polluted drainage water eventually makes its way into traditional water courses and can cause degradation such as increased eutrophication and sedimentation of lakes and rivers, bacterial contamination of recreational waters, pesticide poisoning of water supplies and the natural food chain, and higher concentration of salts and heavy metals. 3.1 Literature Review of Nonpoint Source Pollution "Nonpoint source pollution impacts are site- and source-specific, difficult to identify, and challenging to quantify; assessments of the severity of nonpoint source (NPS) problems in the U.S. vary", according to Humenik (1987). Consequently, it is difficult for professionals to agree on the appropriate level of need for NPS pollution control. The Association of State and Interstate Water Pollution Control Administrators (ASIWPCA) confirms that agricultural activities are the primary contributors of NPS pollution in both lakes and rivers, ahead of urban runoff and resource extraction. "Tillage practices and animal waste management are the most pervasive problems in every region" (Humenik, 1987). "The quality of agricultural runoff depends on the soluble materials which the drainage water comes in contact with, and the suspended material which it carries" (Kilman, 1977). Most animal wastes from feedlots are contained and eventually spread 12 3.0 IMPACT OF AGRICULTURAL DRAINAGE AND ARTIFICIAL AERATION on farm acreage. Manure contains large amounts of BOD, nitrogen, phosphorus, as well as bacteria and pathogens. Manure storage areas and silage can be major sources of pollution if surface and subsurface drainage is not contained, and have often caused fish kills (Lunin, 1971). Groundwater contamination with inorganic nitrogen compounds (nitrites and nitrates) can cause methemoglobinemia in infants (Chanlett, 1979). The amount and composition of feedlot runoff is affected by the land slope, surfacing material, feedlot layout, manure handling and storage practices, animal breed, age, and diet, and environmental factors (Lunin, 1971). Cattle feces contain a variety of stable materials such as lignin and hemicellulose which make up a large fraction of high roughage feeds. By combining plant lignin with bacterial protein, the digestive tract of a cow produces lignoprotein complexes which are very similar to soil humus. These humus-like compounds make up approximately one quarter of the total dry weight of cattle feces (Barker, 1974). Nitrogen compounds from feedlots include several inorganic compounds as well as organic-N from cellular material. Mineral forms of N in soil encompass the following: ammonia, (NH 3), ammonium cations ( N H 4 + ) , nitrate (N03~), nitrite (N0 2"), elemental N (N2), nitrous oxide (N 20), nitric oxide (NO), and nitrogen dioxide (NO2). Nitrate is the most soluble and mobile form; consequently its leaching into water supplies is the greatest N pollution concern (Barker, 1973). Ammonia is present in animal urine as a waste product of protein breakdown (Barker, 1973), and is the major nitrogen constituent which escapes the waste storage facilities (Miner et al., 1980), especially in warm and wet weather (Hansen et al., 1976). Ammonia is toxic to fish and has also been found to harm and inhibit phytoplankton populations (Duffer, 1971). Nitrates are present in animal feces due to the bacterial breakdown of organic-N through the pathways of ammonification and nitrification: 13 3.0 IMPACT OF AGRICULTURAL DRAINAGE AND ARTIFICIAL AERATION Org-N — > N H 4 + — > N 0 2 " — > N 0 3 _ (1) Under appropriate anaerobic conditions, other bacteria in the soil can remove nitrates through denitrification. These bacteria utilize N ions as an electron acceptor, reducing the N and converting nitrates to N 2 or N 2 0 gases which then escape to the atmosphere (Barker, 1973). Denitrification in undisrupted periphyton communities was recently measured by Duff et al. (1984) using chamber experiments with temperature and nutrient levels at ir> situ concentrations. The results from light and dark chambers indicated that "photosynthetic oxygen by periphyton and algal suspensions inhibited denitrification". In-stream and riparian zone (streamside) processes were found to convert inorganic-N to organic forms and also to remove N through denitrification (Lowrance et al., 1984). Finstein (1978) studied nitrification in streams and concluded that planktonic (suspended) as well as nonplanktonic (attached) microorganisms can participate in in-stream nitrification. Many authors have studied the existence of an annual nitrate cycle in agricultural land runoff (Lowrance et al., 1984; Lake and Morrison, 1977; Barker, 1983) finding that the concentration of NO3" in drainage water is highest during the winter months when runoff is highest and uptake by vegetation is at a minimum. There is an additional time of high NO3" runoff after spring fertilization of cropland. The summer growing season shows a reduction in NO3" in drainage water as the precipitation drops, evapotranspiration increases, and while the biological uptake of nutrients is high. A mass balance of N is difficult because of natural sources of N such as rainfall, organic-N in soil which is being converted to mineral forms, and bacterial fixation of N from the atmosphere (Lunin, 1971). Ammonia volatilization and subsequent condensation from feedlot areas can also be extensive enough to cause surface water enrichment (Hutchinson and Viets, 1969). 14 3.0 IMPACT OF AGRICULTURAL DRAINAGE AND ARTIFICIAL AERATION Phosphorus in drainage waters is the major threat for increased eutrophication of surface waters. Skaggs (1980) reports that new agricultural development can greatly increase the P runoff depending on soil type. Phosphate tends to bind to inorganic soils but is considerably more soluble in organic soils. Dissolved phosphate can still bind to inorganic mineral sediments or be adsorbed by stream bank material after it has reached collector ditches. Organic soils with low mineral content release high quantities of P 0 4 " 3 as found during development of land in the tidewater region of North Carolina, where drainage water contained between 1-2.5 mg/l P 0 4 " 3 as P (Skaggs, 1980). Lunin (1971) adds that P 0 4 " 3 retained in soil depends on the pH and texture of the soil as well as the inorganic fraction, but P 0 4 ~ 3 tends to have low solubility and seldom penetrates deep into the soil. The USEPA has reported that phosphates have a strong affinity for clay soils (EPA 430/9-73-014). Phosphorus enters receiving waters primarily through major storm events where large quantities of sediment are eroded from the land surface and are suspended in high water streamflows. Lake and Morrison (1977) found in studies on the the Black Creek watershed in Indiana that 90% of all P in the system was sediment bound (as opposed to only 50% of the N), and the annual P input to surface waters occurred during large storms a few times each year. Similar results were observed by Barker (1983) where the total-P concentration downstream of a swine feedlot increased as much as 5 times following major precipitation events. The algal availability of sediment total-P was studied by Dorich et al. (1980) with sediments from drainage water from the Black Creek watershed, Indiana. Although the most available P for algae is soluble P 0 4 " 3 , his experiments show that 20% of sediment total-P (30% of the inorganic fraction) was taken up by algae after two weeks incubation in the lab. To prevent nonpoint pollution from animal feedlots most researchers recommend preventing outside runoff from entering feedlot areas (Thronson, 1978) 15 3.0 IMPACT OF AGRICULTURAL DRAINAGE AND ARTIFICIAL AERATION and locating feedlots in areas exhibiting compatible topography, soils, and remote surface and groundwater proximity. Surfacing feedlots with pavement has made it easier to harvest manure, but the runoff has higher concentrations of solids, and a higher COD with greater potential for water quality problems (Hansen, 1976). High hydraulic flows from feedlots carry higher concentrations of bacteria (Lake and Morrison, 1977; Duffer et al,. 1971; Hollon, 1982). Runoff must be directed and soil erosion minimized through conservation techniques (Kilman, 1977). Artificial subsurface drainage for cropland lessens the surface movement of runoff, and increases the subsurface movement (Lowrance et al., 1984). Percolation through soil has less pollution potential than does direct surface runoff (Lunin, 1971). Attempts to collect and treat feedlot runoff in anaerobic lagoons have been partially successful in climates where evapotranspiration exceeds precipitation (North Carolina State Univ., 1971); in most cases further treatment of the wastewater is still required to meet discharge permit guidelines (Barker, 1973). Vegetative filtration is more successful at removing N, P, and solids by overland flow of grassy pasture than with channelized flow through pasture (Dickey and Vanderholm, 1981). In fact, with overland flow only the largest runoff events resulted in a partial discharge after 80% of the BOD and nutrients had been removed. The effectiveness of vegetated buffer strips in controlling feedlot runoff has been investigated by Young et al. (1980). Cropped buffer crops on a slope of 4% reduced solids by 79%, lowered total-N and P by 83% and reduced coliform counts. A grassed strip helps to reduce sheet erosion of the soil, reduce flow velocity and encourage deposition of solids (Thronson, 1978). Barker (1983) found that a vegetated swamp provided filtration of a swine feedlot effluent prior to stream input in a North Carolina coastal stream. Lowrance et al., (1984) also employed creekside wetland filtration in a swampy watershed in Georgia. 16 3.0 IMPACT OF AGRICULTURAL DRAINAGE AND ARTIFICIAL AERATION Long (1979) examined the effect of surface-applied dairy cattle manure to Coastal burmudagrass on a sandy loam soil. Manure from 100 cows was applied to 4 ha plots for a 4 year period and compared with plots fertilized with chemical fertilizer. The maximum BOD of surface drainage from the manured plots was 20 mg/l and nitrates averaged below 8 mg/l. Overall yield of grass from manured plots was lower because the manure burned the stems slightly. In addition, pH and conductivity of the runoff from manured plots increased slightly. Applying manure to bare soil works well if it is incorporated into the soil through plowing or disking; this prevents surface runoff (Thronson, 1978). Lunin (1971) adds that applying too much manure can destroy the integrity of the soil, and that pasturing of animals is preferable (North Carolina State Univ., 1971). Dairy feedlot manure disposal by slurry irrigation was studied by Barker (1973). By mixing water with manure to a solids concentration of 1 -4% and sprinkling at at rate of 0.5 inch/hr for 3 hours maximum there was a slight buildup of solids on the surface and runoff BOD, TSS, NO3", and CI" concentrations were increased compared to control plots not receiving slurry irrigation. Shallow wells showed bacteria and NO3" increases of up to ten times. Total organic carbon gives a more rapid and reliable measurement of animal contamination than faecal coliform tests (North Carolina State Univ., 1971). The implementation of nonpoint source pollution control measures in agriculture are best done on a voluntary basis according to Seitz et al. (1982). Because farmers want to remain autonomous, educating farmers of the benefits of NPS control is the best way to change their attitudes and achieve cooperation (Humenik, 1987). Urban runoff was found to be high in BOD in studies by Singh et al., (1979) especially when added to overflow from combined sewers. Novotny et al. (1985) attempted to model the accumulation of urban pollutants on city streets and, after cal-17 3.0 IMPACT OF AGRICULTURAL DRAINAGE AND ARTIFICIAL AERATION ibrating their model they examined weekly street sweeping and found that it removes 50% of the solids build-up but only 25% of the pollutional load at best. 3.2 Literature Review of In-Stream Aeration and Water Quality Modeling River aeration is somethmes implemented to supply supplemental oxygen and increase a river's waste assimilation capacity during critical periods, or as an attempt to reduce the BOD effects of NPS pollution. Differing approaches have been undertaken in the past to artificially add oxygen to natural waters, however, very few river aeration projects appear in the literature. Methods used include weirs, surface aerators, turbine systems, U-tubes, and fine-bubble diffusers. The choice of a river aeration system is usually based on river depth and safety requirements for navigation and recreation, rather than just economics. In deep rivers such as the Ruhr in Germany, turbine aerators were installed and found by Imhoff and Albrecht (1978) to be effective at reducing the oxygen deficit. Surface aerators, common in aerobic sewage treatment lagoons, have also been found to provide inexpensive oxygen to rivers needing it (Whipple et al., 1970). These are essentially submerged turbines which can be mounted on floats and create a intense zone of radial turbulence which entrains air into the water (Metcalf and Eddy, 1979). Consequently, surface aerators can be dangerous for boats, and can also cause a foam buildup on the water's surface. Speece (1979) proposed U-tube aeration with pure oxygen for reaeration of the Chicago urban canal system. He states that U-tube reaeration is more suited to canals than diffused aeration because the initial dissolved oxygen (DO) "deficit is typically much lower and the DO level that must be achieved is typically much higher in canal reaeration applications than in wastewater applications". By supersaturating a sidestream of the canal flow to 34 mg/l using pure oxygen and blending this water 18 3.0 IMPACT OF AGRICULTURAL DRAINAGE AND ARTIFICIAL AERATION back into the canal through bottom diffusers high increases in DO can be achieved economically. A fine bubble diffuser installed in the Passaic River, N.J., at a depth of 3.05 m achieved a transfer efficiency of 7% (Shaw and Yu, 1970). In streams where the oxygen deficit is less than 50% of saturation, the use of molecular oxygen becomes more economical than air because it can achieve a much higher driving force (Amberg etal., 1969). Meadows et al. (1978) studied a small stream draining a watershed with mixed land use and found high BOD associated with lateral drainage from commerce and industrial land use areas, and to a lesser degree residential areas. Agricultural and forested areas actually showed a negative correlation with instream BOD. Damaskos and Papadopoulos (1983) developed a mathematical stoichastic model for BOD and DO prediction for any point on a stream. Lee (1985) showed that geographical models can be used to provide distributed hydrologic models of nonpoint pollution from agricultural watersheds. Bathala et al. (1979) found that the assimilative capacity of small streams for secondary sewage effluent was drastically reduced during summer periods of low flow and high temperature. A water quality model was developed and calibrated in order to estimate what further treatment could be added to the two existing treatment plants to lessen the DO sag and improve the water quality of the creek during the summer months. Shelton et al. (1978) conducted a similar study in a slow moving creek where both carbonaceous and nitrogenous wastes were contributing to DO problems downstream of a wastewater treatment plant. Photosynthesis/respiration and benthic oxygen demands played a much larger role in this stream than in the study by Bathala et al. (1979). Rickert (1984) has done a similar study on the Willamette River, in Oregon, where many large municipalities contribute sewage effluent to a large river system with roughly 17 days retention time. "Determination of the role of industrial 19 3.0 IMPACT OF AGRICULTURAL DRAINAGE AND ARTIFICIAL AERATION ammonia in oxygen depletion led to reducing the need for advanced waste treatment by municipalities." Wright et al. (1979) reviewed 23 rivers receiving secondary sewage effluent in an attempt to relate the BOD removal rate to channel characteristics. The deoxygenation rate (Kd) of rivers after normalization to 20 °C was found statistically to depend closely on flowrate (Q), the wetted perimeter (P), and also on the hydraulic radius (Rh), and values of Kd are given for various types of streams. 3.3 Past Research on Water Quality of the Serpentine River Partly as a result of fish kills, numerous reports have been prepared on the water quality of the Serpentine River during the last few years. Almost all researchers have identified potential water quality problems as: (1) fluctuating DO levels which are above saturation during summer and low in the autumn, (2) high summer water temperatures which could be lethal to migrating salmon and trout, (3) fluctuating pH during the summer, which occasionally rise above EPA recommended limits, (4) high organic carbon, (5) high levels of nutrients such as ammonia and nitrates, and (6) phosphates. Cox (1975) studied various proposed drainage and irrigation schemes for the farmlands in the Serpentine/Nicomekl watershed and recommended against diverting water from the Fraser River for irrigation of the valley. He urged officials to adopt an integrated watershed management approach to protect fish and wildlife populations and their habitat when striving to meet agricultural objectives. Cox and McFarlane (1978) studied fish and wildlife populations and habitat in the Serpentine/Nicomekl watershed with the objective of preserving valuable habitat areas. Excellent spawning and rearing habitat areas were found in the upstream mainstem of the Serpentine River in Tynehead Park and in Mahood Creek. Latimer Creek, despite a shortage of good spawning gravel was used by coho and to a lesser 20 3.0 IMPACT OF AGRICULTURAL DRAINAGE AND ARTIFICIAL AERATION extent by cutthroat. Clark and Truelson (1977) found a very small number of benthic invertebrates (oligochaetes and chironomids) in the creek sediments, and felt that the creek was too heavily silted to be of much enhancement value for fish. Their report includes detailed information concerning the habitat, benthic species, and fish in all of the tributary creeks of the Serpentine and Nicomekl Rivers. Bourque and Hebert (1982) gathered not only water quality data during 1974-75, but also sampled bottom macroinvertebrates, periphyton, and examined metals in fish flesh. Of the 17 macroinvertebrates genus' identified, 5 are classified as pollution sensitive, 9 as moderately tolerant, and 2 as pollution tolerant. In 1984, the BC Waste Management Branch became sufficiently concerned with the recurring fish kills that they initiated the installation of experimental in-stream artificial aeration. Moore (1984) explained that low DO levels in river water reduce the oxygen partial pressure which the gills utilize in order to transfer oxygen from the water into the blood. If the oxygen gradient is sufficiently lower, the necessary quantity of oxygen cannot be transfered to the blood. Davis (1975) reports that rainbow trout blood remains nearly 100% saturated with oxygen until the partial pressure of oxygen drops below 80 mm Hg (or approximately 9.6 mg/l at 5 °C), at which point more circulatory and ventilatory work must be done to meet the oxygen requirements of the tissues. Dissolved oxygen levels less than 6.4 mg/l can harm a mixed fish population; DO values below 3.9 mg/l would result in a severe impact if they last for more than a few hours. Although river aeration was recognized as a temporary solution to the DO problem, it was seen as an attempt to save the fish stocks and provide the necessary time to implement long-term NPS control measures. The Environmental Engineering Group at the University of British Columbia became involved by designing and installing a diffused-air aeration system as a graduate student research project. The aerator installation was carried out in the sum-mer and autumn of 1985, together with a river sampling program which attempted to 21 3.0 IMPACT OF AGRICULTURAL DRAINAGE AND ARTIFICIAL AERATION determine it's effectiveness. Warm, dry weather in September was followed by a rainy October and an unseasonably cool November; this did not create a high oxygen deficit in the river, and the aerator was largely untested. A strong correlation between declining chlorophyll-a levels and reduced dissolved oxygen in the autumn indicated that dying algae were exerting a substantial oxygen demand. The sampling program also identified Latimer Creek as a large contributor of oxygen demanding pollutants (Town, 1986). Since that time, Duncan (1986) used in-situ production/respiration chambers to assess the importance of agricultural discharges on river DO levels surrounding the first flush rainfall of late summer. In addition, he tested water in a ditch draining a dairy farm containing approximately 150 cattle, and 1:1 mixtures of this drainage with river water. The DO demand of these samples was 0.45 g 0 2 / m 3 / h r and 0.1 g 02/rrvtyhr, respectively. Although his results were preliminary, Duncan concluded that agricultural runoff is the primary factor causing serious DO depletion in the Serpentine River. 22 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY 4.1 Introduction This sampling program was designed by taking into account the findings of past water quality research on the Serpentine. The main purposes of this sampling program were: (1) to generate water chemistry data which would help to assess the potential severity of several dairy farm drainage ditches which empty into the Serpentine, (2) to contribute additional information to the problem of a large summer algae bloom followed by an autumn die-off, thought to contribute a substantial biochemical oxygen demand the river and deplete oxygen levels, and (3) to assess the effectiveness of the aeration system installed in the lower Serpentine during the summer of 1985. A total of nine stations were selected to accomplish the above objectives, and still fit within the budget constraints. Weekly grab samples were collected every Tuesday from July 14 to December 1, 1987, starting at the upstream sites in the morning and moving progressively downstream. Field measurements included dissolved oxygen and temperature, and some depth profiles included conductivity measurements. Two sets of samples were collected simultaneously: one set (750 ml plastic bottles) for analysis at the UBC Environmental Engineering (EE) laboratory and the other (1.5 I plastic bottles) for the BC Ministry of Environment laboratory at the BC Research Station. Samples were stored in a cooler with ice while under transportation and in refrigerators at 4 °C; once in the laboratories water chemistry analysis was begun the following day. Every effort was made to ensure that the samples collected were representative of the state of the river at that given time. In shallow regions of the river, grab samples were taken carefully from the surface, so as not to incorporate sediments from the bottom. When surface mats of algae covered parts of the river, samples were taken 23 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY from one half meter below the surface by removing the stopper after the sample bottle was submerged. Duckweed was removed from ditch samples. 4.2 Sampling Locations. Site Descriptions, and Flow Patterns Seven of these sampling locations concentrated on assessing the affect of farm drainage in the vicinity of Harvie Rd south of Latimer Creek and north of 72nd Ave. Two drainage ditches which collect runoff from dairy farming operations were selected. Town (1986) had identified Latimer Creek as a "definite source of contaminants to the Serpentine River", and so further sampling of Latimer Creek was undertaken in this study. The other two sampling sites were located upstream and downstream of the aerator site in order to estimate the effect of the aerator. The distance between the most upstream and most downstream sampling locations is 14.8 km; sampling sites are shown on Figures 5 and 6. The author has attempted to give the sample sites mnemonic labels based on the names of streets which cross the river. As an aid to the reader, the labels of all sampling locations on the Serpentine River begin with the word "Site". Site 176 - Intersection of the Serpentine River with 176th St. This site is the most upstream of the sampling sites on the river itself and is located at the uppermost end of the flood plain; the dykes extend upstream only 1.0 km further. The water here is as little as 0.25 m deep in summertime, and the width is 2-3 m. The speed of the flow was never less than 0.5 m/s in the course of this study. Dairy Ditch 1 - This sampling site is a drainage ditch which runs from a dairy farmer's barn area through a grassed field and past a flap valve into Latimer Creek. This ditch measured roughly 1.25 m wide and 0.6 m deep. In dry weather, the flow out though the 0.3 m pipe was 3 - 5 l/min, although there were some times when there was no flow at all. 24 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY ® SAMPLING SITES S c a l e I ' S O O O O Figure 5. Map Showing Sampling Sites on the Serpentine. (From Moore, 1984) 25 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY Figure 6. Map Showing Sampling Sites for Dairy Ditches and for Latimer Creek. (From National Topographic Series, 1977) 26 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY Latimer U/S - This sampling site was located just 2 m upstream of the confluence of Dairy Ditch 1 with Latimer Creek. The dry weather depth of the stream at this point averaged 20 cm and the width is 1.0 to 1.5 m. The velocity was typically 0.5 m/s. Latimer D/S - This sampling site was located roughly 8 m downstream of the of the confluence of Dairy Ditch 1 with Latimer Creek. The creek was narrower and faster flowing at this point, and provides some turbulent mixing for the ditch flow. Harvie Rd Ditch - Running parallel to Harvie Rd, this ditch is a collector for a number of smaller ditches which drain pasture used to graze dairy cows. It flows southwest along Harvie Rd until it intersects Fraser Hwy, after which it flows northwest and drains into the Serpentine. The author never observed a visible flow velocity in this ditch. Site 80 - Intersection of the Serpentine River with 80th Ave. This site is located 1.9 km downstream of Site 176 and 725 m below the confluence of the Serpentine River with Latimer Creek. At this point the river is approximately 12 m wide, and the summer depths range from 0.5 to 1.75 m. The river behaves like an impoundment from this point downstream to the tidal gates, often with little or no flow velocity. During the course of sampling there were numerous occasions when the author recorded a slow upstream flow at this location. Site FH - Intersection of the Serpentine River with Fraser Hwy. This site is 3.0 km downstream from Site 176 and 1.1 km downstream from Site 80. The river is close to 16 m wide, and varies in summer depths from 0.75 to 2.0 m. Similar to Site 80, there is often a slow upstream flow at this site. A few m from the bridge at Fraser Hwy three large flapped culverts (1.0 m diameter each) drain a ditch system which encompasses a dairy farm located on sloped ground just on the edge of the floodplain. The Harvie Road ditch is part of this system. 27 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY Site #10 - Intersection of the Serpentine River and #10 Hwy. Located 7.7 km downstream from Site FH, this sampling site is just 1.5 km upstream from the aerator, as shown in Figure 7. The river is approximately 20 m wide and ranges from 1.0 to 2.25 m deep. Site 152 - Intersection of the Serpentine River and 152nd St. This sampling location is 4.1 km from Site #10 and 2.6 km downstream from the aerator. The river is 30 m wide and has depths which range between 2.0 and 3.25 m. 4.3 General Water Quality Methods 4.3.1 Dissolved Oxygen (DO) Dissolved oxygen was used to measure the oxygen deficit on the river as well as the ditch and creek sites. A YSI (Yellow Springs Instrument Co.) dissolved oxygen probe and meter was calibrated by the Winkler method in the laboratory, and 4 Winkler tests were performed with field samples on each sampling trip in order to further verify the DO probe results. 4.3.2 Temperature Temperature affects the DO saturation concentration and affects the health and survival of fish and other organisms. In addition, temperature/depth profiles provide additional information about the degree of surface warming, mixing, and groundwater infiltration. Temperature was measured using a YSI temperature probe, incorporated into the DO probe. 4.3.3 pJH pH was measured in the laboratory with a Beckman I44 pH meter, previously calibrated to solutions with known pH. 28 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY Figure 7. Map of the Lower Serpentine Floodplain, location of Aerator and Tidal Gates. (From National Topographic Series, 1977) 29 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY 4.3.4 Specific Conductance Specific conductance was determined to estimate the extent of dissolved salts in the agricultural drainage water, and saline water intrusion in the river near the tidal gates. Samples were brought back into the laboratory and measured using a Radiometer CDM3c conductivity meter. Field conductivity profiles at Sites 152 and #10 were determined with a YSI Model 33 temperature/conductivity meter. 4.3.5 Chlorophvll-a (Chl-a) Chlorophyll-a was tested weekly at all sites to provide some estimate of the phytoplankton biomass in the river. Chl-a, a photosynthetic pigment, is normally the most abundant and important pigment in green plants carrying out photosynthesis (Vollenweider, 1974). Large amounts of algae can be present in highly fertilized water systems, and contribute profoundly to the oxygen budget while undergoing the diurnal cycle of respiration and photosynthesis. A chloroform-methanol extraction of Chl-a (Wood, 1985) was used to remove the pigment from the cellular material, and the fluorescence of the extracted samples was measured on a Turner Designs Fluorimeter (Model 10). A standard-curve enabled the sample fluourescence values to be converted into Chl-a. 4.4 Methods Used to Assess Dairy Farm Drainage Parameters chosen to evaluate the extent of pollution caused by agricultural drainage encompass compounds containing carbon, nitrogen, and phosphorus. This study examines a set of parameters similar to those selected by Town (1986) to facilitate comparisons between the studies and broaden the data base. 30 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY 4.4.1 Chemical Oxygen Demand (COD) A COD test measures the equivalent of the oxygen that would be required to react with the organic material in a water sample. According to the open reflux method (APHA et al., 1985) a strong chemical oxidizer (K2Cr 2 0 7 ) is added to samples and the mixture boiled for two hours. Samples known to have high specific conductance were analyzed with H g S 0 4 to eliminate chloride interference. These included the two ditch samples, and on occasion the Site 152 sample. Other interferences include N H 3 , NO2", and some reduced inorganic species. Field samples were collected in 250 ml plastic bottles, and were analyzed in the UBC Environmental laboratory the following day. 4.4.2 Total Organic Carbon (TOC) The total organic carbon test is a direct expression of organic carbon, and is preferred over the BOD and COD tests by some researchers (North Carolina State Univ., 1971) because the TOC provides a more reliable indicator of organic pollution. The combustion-infrared method (APHA et al., 1985) was utilized with a Beckman TOCA and CO2 infrared analyzer. Total carbon (TC) was determined in the 950 8 C combustion chamber, and inorganic carbon (IC) in the 150°C chamber. Total organic carbon (TOC) was determined by the difference between TC and IC. Samples were unfiltered, and were without added preservatives. 4.4.3 Total Ammonia/Ammonium Ammonia is present in animal waste and is produced by the heterotrophic breakdown of organic material. In addition, many zooplankton excrete ammonia as a waste product of metabolism (Cole, 1983). Ammonia can exert a DO demand when discharged into surface waters and nitrifying bacteria convert it to nitrates. Un-ionized ammonia can also be directly toxic to fish; the US-EPA recommends that maximum 31 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY levels of un-ionized ammonia should not exceed 0.020 mg/l (as N), for the protection of fish (Hellawell, 1986). An auto-analyzer was used to determine total ( N H 3 / N H 4 + ) according to the automated bertholot method (Technicon Instrument Corp., 1973). Analysis was carried out at the BC MOE laboratory, and levels are reported in mg/l N. 4.4.4 Nitrate/Nitrite Nitrogen Nitrate is an immediately available nutrient for algae. Total nitrate/nitrite (NO3" ,N02_) were determined using the automated cadmium reduction method (APHA et al., 1985), and Nitrite was analyzed by Automated Diazotization (APHA et al., 1985). The difference between these two values is the nitrate concentration expressed as mg/l N. Analysis was carried out by the MOE laboratory for the first 12 weeks, and at the UBC-EE laboratory for the remaining 9 weeks. Quality control between the two laboratories was assured by analyzing eighteen duplicate samples on Oct 7 and Oct 14; results were within 5% of each other. 4.4.5 Organic Nitrogen Organic nitrogen contributes to the water column both nutrients and oxygen demanding material. Org-N is the difference between the total kjeldhal nitrogen (TKN) and total ammonia, with TKN analyzed using the block digestive automated colourimetric method (APHA et al., 1985). Analysis was carried out at the MOE laboratory. Duplicate TKN was analyzed at the UBC-EE laboratory for the final 9 weeks of the study. Results from the two laboratories were within 5%, indicating that quality control between the two laboratories was quite satisfactory. 4.4.6 Ortho-Phosphate Dissolved ortho-phosphate (P0 4~ 3) often controls the amount of plant growth in fresh water systems, since most organisms can readily use it. However, P 0 4 " 3 32 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY adsorbs readily to clay particles or can precipitate out of solution. The automated ascorbic acid (AAA) procedure was used to determine P 0 4 ~ 3 levels, giving results as mg/l P. Analysis was carried out by the MOE laboratory for the first 12 weeks, and at the UBC-EE laboratory for the remaining 9 weeks. Quality control between the two laboratories was assured by analyzing eighteen duplicate samples on Oct 7 and Oct 14; results were within 5% of each other. 4.4.7 Total Phosphorus Total-P includes not only PO4" 3 , but also organic phosphorus. All phosphorus forms are digested to PO4" 3 , and then analyzed using the AAA procedure. Analysis was carried out by the MOE laboratory for the first 12 weeks, and at the UBC-EE laboratory for the remaining 9 weeks. Quality control between the two laboratories was assured by analyzing eighteen duplicate samples on Oct 7 and Oct 14; results were within 5% of each other. 4.5 Methods Used to Assess Aerator Performance In order to test the in-stream aeration system, an identifiable slug of water was to be monitored as it flowed downstream through the aeration zone. Ideal testing of the system is a hit-and-miss proposition, because it combines the occurrence of natural events which cannot be predicted (and may not occur at all) with sensitive equipment which can malfunction. Firstly, ideal conditions for testing the aeration system would be when the river was experiencing a severe DO deficit. The aeration system would be operating with a high oxygen driving force, so that oxygen in the air bubbles would move more readily across the air/water interface and into the water. Secondly, the tidal gates would have to be open for a sufficient time to allow the river to flow from the upstream monitoring station through the aeration zone and past the 33 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY downstream monitoring station; such occasions are rare. Finally, the monitoring equipment must be in place, and functioning properly. 4.5.1 Hvdrolab Data Dissolved oxygen monitoring upstream and downstream of the aeration system was to be carried out by continuous-monitoring Hydrolab systems (Hydrolab Corp., Austin Texas), which were set up at Sites #10 and 152. These would to measure pH, temperature, DO, and specific conductance both upstream and downstream of the aerator at 160th St. The units were located in strongboxes which were bolted to existing bridges to prevent vandalism. The Hydrolab unit in place at Site #10, provided by the EPS, had a datalogger which was programmed to record a value for each parameter every half hour. The probe was mounted near the centre of the river, roughly 0.4 m above the bottom. The water depth above the probe ranged from 0.6 to 1.85 m; this depth ensured the top of the probe would remain submerged, making it a less obvious target for vandalism. At Site 152, a Hydrolab D3 with multiplexor and Rustrack strip-chart recorder were secured on the bridge. The probe was located 1.0 m off the bottom near the middle of the river. This piece of equipment was on loan from the MOE Waste Management Branch and had many operational problems. Despite numerous repairs and adjustments, no usable data was obtained from this unit throughout the entire duration of the study. To partially compensate for the lack of data from the hydrolab at Site 152, a YSI dissolved oxygen probe and Moseley 680 strip chart recorder were installed 100 m downstream of the aerator at 160th Street. This provided only DO readings on a continuous basis, although this instrument did not function for some time during the month of October. 34 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY 4.5.2 Depth Profiles of Dissolved Oxygen. Temperature, and Conductivity Depth profiles of dissolved oxygen (DO), temperature, and specific conductance were performed at Site #10 and 152. Dissolved oxygen and temperature profiles were initiated to better understand the algal DO contribution due to photosynthesis. Because of poor light penetration, high dissolved oxygen measured in the surface waters was not expected to be typical of the waters below. The extent of surface warming of the river during warm weather was measured weekly from Sept 22 to Nov 17. Specific conductance measurements were added from Oct 27 to Nov 17 to confirm the suspected existence of a wedge of salt water at Site 152. Visual inspections of the tidal flood gates at Hwy 99A had shown salt water leaking into the river channel during high tide events. 4.6 Additional Information Gathered Atmospheric Environment Services provided daily precipitation and temperature data from four stations in the vicinity of the Serpentine watershed. In the upper Serpentine watershed, one station was located at the intersection of 132nd St and Fraser Hwy, and the other at the Whalley Forest Nursery (7165J and 8120J). In the lower Serpentine, one station is located at the Surrey Municipal Hall (intersection of #10 Hwy and Hwy 99A) and the other near the intersection of Hwy 99A and 72nd Ave (1740J and 7160). These locations are shown in Figure 4. Water level records were obtained from the Municipality of Surrey from the following recording stations: Serpentine River at #10 Hwy, Serpentine River at Fraser Hwy, and Latimer Creek at 188th St. These were used to determine when the river was actively draining through the tidal gates into Mud Bay, and identify periods when the gates were closed and the river acts like an impoundment. 35 4.0 SAMPLING PROGRAM AND EXPERIMENTAL METHODOLOGY 4.7 Statistical Correlations Statistical correlation coefficients (r) were calculated in order to assess the degree of linearity between two measured parameters (Devore, 1982). (-1 < r ^ +1; r values near +1 indicate a strong linear relationship, and near zero indicate the absence of a linear relationship.) These were computed by hand on a Hewlett-Packard 15C calculator; r values are quoted frequently throughout the text. 36 i 5.0 RESULTS AND DISCUSSION 5.1 Analysis of Data All water quality data from all sampling locations on the river and the drainage ditches is presented in Appendix I. As discussed previously, these data are based on weekly grab sampling from the water surface. A summary is presented below. 5.1.1 Water Quality of Serpentine River 5.1.1.1 Dissolved Oxygen (DO) Surface dissolved oxygen data at Sites 176, FH, and 152 is given in Figure 8. At Site 176, DO remained relatively constant at 7 to 9 mg/l during the summer when the water temperatures were typically 15 °C, and increased steadily throughout the autumn as temperatures drop. At Site FH the DO was erratic, varying between 7 and 13 mg/l during the summer, with a similar DO pattern observed at Site 152. As evident in Figure 9, DO remained below saturation at Site 176 during the entire study. At Site 80, however, a substantial DO demand is present, but during the summer months supersaturation conditions are normal at Site FH, just 1.1 km downstream. Early October, however, marks a turning point in the algal production of DO at Sites 80 and FH, and DO hovered near 50% saturation for the following 6 weeks. Two processes are likely occurring: decaying algae are exerting an oxygen demand, and the photosynthetic oxygen production of the remaining viable algae has decreased in response to cooler weather and fewer hours of daylight. It is evident in Figure 8 that it took several weeks for this oxygen-deficient water to manifest itself in the lower floodplain (Site 152), due to the very low flushing rates of the river. The lack of rainfall indicates that the low oxygen conditions could not have been caused by agricultural drainage water (known to have high BOD) being flushed into the river. Precipitation for the Serpentine watershed is given in Figures 10 and 11, and 37 DISSOLVED OXYGEN ALONG S E R P E N T I N E > n i 1 1 — i i i i i i i i i i i i i i i 1 1 JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 Figure 8. Dissolved Oxygen Along Serpentine Length, Sites 176, FH, & 152. DISSOLVED OXYGEN SATURATION • • SITE 176 SITE 80 SITE FH Hr-20% —i 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 i r— JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 Figure 9. Dissolved Oxygen Saturation for Upper Serpentine, Sites 176, 80 & FH 50 40 -30 -20 10 0 JUL 14 AUG 04 SEP 01 i I r SEP 29 OCT 27 NOV 24 Figure 10. Precipitation for the Upper Serpentine Watershed. (Data From Atmospheric Environment Services, 1987) 50 40 -30 -20 10 -0 cn b 3J m <z> c CO > z o g « o c CO CO O z l r JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 Figure 11. Precipitation for the Lower Serpentine Watershed. (Data From Atmospheric Environment Services, 1987) 5.0 RESULTS AND DISCUSSION and illustrates clearly that the first major autumn rainfall occurred as late as Oct 30 and 31. One earlier 8 mm rainfall event occurred on Sept 14; DO was reduced in all regions of the river on Sept 15 as shown in Figures 8, 9, and 12. This was probably due to some water containing biodegradable organic matter leaving the swollen drainage ditches and flowing into the river. Surface DO in the lower Serpentine (Figure 12) is almost always supersaturated during the summer months. Dissolved oxygen/depth profiles at Sites #10 and 152 are given in Figures 13 and 14, and show clearly that the high DO measured on the surface decreases dramatically with depth during summer and early autumn. Figure 14 shows DO over 13 mg/l at the surface, 3.5 mg/l at 1.0 m depth, and 2.0 mg/l at 2.0 m depth. This appears to be evidence of a combination of a benthal oxygen demand and poor mixing of the water column due to density stratification (caused by a wedge of salt water which migrates upstream from the tidal gates). The high algal DO contribution on the surface disappeared towards the end of October; this coincided with the onset of autumn rains. Oct 27 marked the beginning of 3 weeks of depressed oxygen in the lower regions of the river while the watershed was flushed. Dissolved oxygen/depth profiles during this period do not vary appreciably from surface to bottom. Dissolved oxygen varied along the length of the river dramatically as shown in Figures 15 and 16, with the most critical region of the river near Sites 80 and FH. The DO depression observed throughout the length of the river on Sept 15 is likely due to rainfall which occurred on Sept 14, as discussed earlier. From Figure 15, there does not appear to have been an extended period of low DO in the river in the vicinity of the aerator from Sept 08 to Sept 22. Chlorophyll-a levels throughout the river system are shown in Figures 17, and 18, and indicate clearly that most of the growth of algae took place in the floodplain, where water velocities are slow. A decline in the Chl-a levels took place towards the end of October. Because Chl-a extractions do not distinguish between dead and living 42 Figure 12. Dissolved Oxygen Saturation for Lower Serpentine, Sites #10 & 152. 0 0.4 -0.8 -g 1.2 -I W P 1.6 -2.4 0 D O / D E P T H PROFILE AT SITE #10 \ \ . »•— \ \ \ / T T SEP 22 OCT 06 OCT 20 NOV 03 NOV 17 1 r ~ 4 6 8 10 12 14 16 DISSOLVED OXYGEN ( m g / l ) 18 20 cn b 3) m w c CO > z D O CO O c co CO O z Figure 13. Dissolved Oxygen/Depth Profile at Site #10. D O / D E P T H PROFILE AT SITE 152 SEP 22 OCT 06 OCT 20 NOV 03 NOV 17 0 2 4 6 8 10 12 14 16 18 20 DISSOLVED OXYGEN ( m g / l ) Figure 14. Dissolved Oxygen/Depth Profile for Site 152. CD o CO CO 1—4 p 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 DO ALONG SERPENTINE LENGTH AERATOR RUNNING FULL-TIME BEGINNING OCT 15 • • SEPT 08 + + SEPT 15 * o SEPT 22 b m CO c C O > z a g CO o c C O CO O BS O &• O o 3 o t 0 2 4 6 8 10 12 DISTANCE FROM SITE 176 (km) 14 Figure 15. Dissolved Oxygen Along Serpentine Length, Sept 08,15, 22. DO ALONG SERPENTINE LENGTH -si O CO CO i—< Q 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 AERATOR RUNNING FULL-TIME BEGINNING OCT 15 33 rn CO c C O > z o g CO o c CO CO o z — i r 0 2 T " 4 i 6 8 10 12 DISTANCE FROM SITE 176 (km) 14 Figure 16. Dissolved Oxygen Along Serpentine Length, Oct 13, 27, Nov 10. C H L O R O P H Y L L - A IN U P P E R SERPENTINE 240 - r 220 -200 -180 -160 -140 -120 -100 -80 -60 -40 -20 -• SITE 176 •t- SITE 80 SITE FH —i 1 1 1 1 — JUL 14 AUG 04 SEP 01 SEP 29 i i i r OCT 27 NOV 24 Figure 17. Chlorophyll-a in Upper Serpentine, Sites 176, 80 & FH. Figure 18. Chlorophyll-a in Lower Serpentine, Sites #10 & 152. 5.0 RESULTS AND DISCUSSION algae, it is probable that the algal die-off occurred sometime in mid October, prior to the actual decline in Chl-a values. Correlation coefficients (r) have been calculated for DO and Chl-a from Aug 27 to Nov 10 in order to determine the degree of linearity. Sites FH, #10, and 152 have coefficients of 0.43, 0.78, and 0.39 repectively, indicating that the relationship between DO and Chl-a is weak. Figures 9 and 12 show photosynthetic DO production had declined noticeably by Oct 20, suggesting that the algae in the upper floodplain of the river most likely died-off at this time. Surface DO was no longer supersaturated at Sites #10 and 152, and Figure 8 indicates that the DO averaged 6 mg/l for extended periods of time (DO was as low as 3.8 mg/l at Site FH on Nov 03). This was simultaneous with the decrease in Chl-a levels mentioned above, and more importantly occurred prior to any major autumn rainfall (which took place on Oct 30-31). It is clear from these data, that this lingering DO deficit was caused by a combination of decreased photosynthetic oxygen production and an oxygen demand exerted by decaying algae; there was insufficient rainfall to flush high BOD agricultural drainage from farm ditches into the river. The depressed oxygen levels did not cause a fish kill, likely because the algae decay and the influx of high BOD agricultural drainage did not occur simultaneously. Cooler temperatures also slowed the decomposition of the dead algae. Rainfall, once it began, increased steadily for a full month (with very few dry days) giving high river flow rates and good flushing. Organic material from both the dead algae and the new influx from the drainage ditches was flushed from the river system quickly. Earlier results from the continuous-monitoring hydrolab, installed at Site #10, are shown in Figures 19, and 20, together with ocean tides and river levels. Dissolved oxygen levels in the river fluctuated wildly during these four days, and frequently dropped below 4.0 mg/l for a few hours. Figure 20 even shows that the DO went down to 0.4 mg/l briefly on Sept 24. This may be evidence of a high benthal oxygen demand, likely due to some early dead algae dropping out of suspension and settling 50 Figure 19. Dissolved Oxygen and Water Levels versus Time, Sept 21 and 22. DO AND WATER LEVELS VS TIME « o OCEAN TIDE LEVEL a a LEVEL AT SITE FH DO AT SITE #10 0 12 24 12 TIME (HOURS) Figure 20. Dissolved Oxygen and Water Levels vs Time, Sept 23 and 24. 5.0 RESULTS AND DISCUSSION to the bottom. Diurnal fluctuations in oxygen levels illustrate the effects of photosynthesis and respiration. Although daylight would initiate photosynthesis in the surface waters before 1100 hrs, there is a lag time of roughly three hours before oxygen levels climb; this is likely due to afternoon winds which induce mixing of the river waters and circulate the surface waters down to the depth of the DO probe. Algal photosynthesis and respiration are further illustrated in Figure 21, and were similar to that observed by Town (1986). Respiration was evident by falling DO levels beginning at about 1900 hrs when the daylight conditions had ended, and continued until roughly 1100 hrs the following day when photosynthesis began again. As the weather cooled in the autumn, the hours of sunlight decreased, productivity decreased, and the algae began to die; by Nov 03 no fluctuation of DO could be seen at all. The reader is reminded that the hydrolab probe was situated 0.4 m above the river bottom, with the depth of water above the probe varying between 0.6 and 1.85 m. Consequently, DO levels from this hydrolab do not reflect surface algal DO contributions which occur in the upper 1 m; this is supported by the DO/depth profiles in Figures 13 and 14. 5.1.1.2 Temperature Temperature readings are given for Sites 176, FH, and 152 in Figure 22. Water temperatures were lowest at the upstream sampling locations and increased progressively downstream. There are two likely reasons for this temperature increase. Firstly, the upland streams are primarily groundwater fed during the summer months, and move towards the river through shaded gullies without having enough time to fully warm to the surrounding air temperatures. Once in the floodplain of the river, however, the water moves more slowly, and with the absence of trees shading the river, the water temperature warms to match the ambient air temperature. Secondly, river sampling was done beginning at the upstream sites and moving progressively 53 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 DO VS TIME FOR VARIOUS TIME PERIODS SEP 21 '' " X SEP 28 OCT 08 OCT 17 NOV 03 — ' r-^-RESPIRATION PHOTOSYNTHESIS 1900 2300 0300 0700 1100 TIME (HOURS) 1500 1900 Figure 21. Dissolved Oxygen Variation for a 24 Hour Period, Site #10, Photosynthesis and Respiration. b 33 m CO c CO > Z O D CO O c CO CO o z TEMPERATURE ALONG SERPENTINE > n i—i—i—i i i i i i i i i i — i — i — i — i — i — i — i JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 Figure 22. Temperature Along Serpentine Length, Sites 176, FH, and 152. 5.0 RESULTS AND DISCUSSION downstream. Site 176 was typically sampled in the morning (0930-1100 hrs), when the air was cooler, and Site 152 in the afternoon (1330-1530 hrs). Temperature/depth profiles in Figures 23 and 24 indicate that surface warming of the river occurred at Sites #10 and 152 throughout the early autumn until mid October. River temperatures at the surface correspond to mean air temperatures mea-sured from the four AES climatic stations mentioned previously, and given in Figure 25. River temperatures during the months of July and August were dangerously high for coho fry and adult steelhead. This has been well discussed in reports by Bourque and Hebert (1982) and Town (1986) which both state that "the incipient lethal temperature for coho fry is 25 °C and for adult steelhead it is 21 °C". High water temperatures can also lead to excessive growths of algae and eutrophic conditions, as well as speeding the metabolism of bacteria. 5.1.1.3 pJH pH values for Sites 176, FH, and 152 are presented graphically in Figure 26, and illustrate that the pH of the river was highly variable during the warm weather of summer and autumn. Summertime pH values ranged between 6.94 and 9.16 (with one exception at Site 176) but tended to fall throughout the autumn to values between 5.78 and 7.0. Along the river's length, the pH normally increased from the upstream sampling stations to those downstream, although the pH increase was less noticeable as winter approached. In fact, very heavy rainfall from Nov 10 to 15 lead to a pH of 6.0 throughout the entire length of the river. This trend for falling pH during the autumn has been well documented by previous researchers. Sprout and Kelley (1961) classified almost all of the soils in Surrey Municipality as highly acidic (the pH of 40 different surface soils range from 3.6 to 6.2; average 5.0). Cox and McFarlane (1978) stated that because of acidic soils, the drainage water which runs off the land and leaches through the soil is inclined to be 56 TEMPERATURE PROFILE AT SITE #10 SEP 22 OCT 06 OCT 20 NOV 03 NOV 17 I I l I l I I I I I I I I 0 2 4 6 8 10 12 14 16 18 20 22 24 26 TEMPERATURE f C ) Figure 23. Temperature/Depth Profile for Site #10. TEMPERATURE PROFILE AT SITE 152 SEP 22 OCT 06 OCT 20 NOV 03 NOV 17 —I 1 r—i 1 1 1 1 1 1 1 1 — 0 2 4 6 8 10 12 14 16 18 20 22 24 26 TEMPERATURE f C ) Figure 24. Temperature/Depth Profile for Site 152. MEAN DAILY TEMPERATURE ON SAMPLING DAYS - ~ i i — i — i — i — i — \ — i — i — i — i — i — i — i — i — i i i I i i JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 Figure 25. Mean Air Temperature on Sampling Days, Upper and Lower Serpentine (Data from AES). 11 pH ALONG SERPENTINE L E N G T H 10 H 9 H 8 • • SITE 176 + SITE FH o. <> S I T E 1 5 2 4 n 1 1 1 1 1 r JUL 14 AUG 04 SEP 01 n i i i i i i i i 1— SEP 29 OCT 27 NOV 24 Figure 26. pH Along Serpentine Length, Sites 176, FH, & 152. 5.0 RESULTS AND DISCUSSION acidic. During the summer growing season, this effect is counteracted by the addition of alkaline fertilizers containing calcium and lime. Rainfall increases in autumn; this together with the termination of fertilizer application results in a return to acidic conditions in the river. Previous researchers have also noted a positive correlation between pH and high DO during the summer. Bourque and Hebert (1982) and Town (1986) concluded that high rates of photosynthesis alters the carbonate buffering capacity of the water. Following is the well known carbonate equilibrium equation, which usually is responsible for a natural water's ability to resist changes in pH : C 0 2 + H 2 0 < —> H 2 C 0 3 <--> H + + HCO3- <---> H + + CO3-2 (2) As explained by Town (1986), photosynthesis consumes C 0 2 and shifts the equilibrium reactions to the left. This consumes H + ions and raises the pH as a result. Bourque and Hebert (1982) reported that the alkalinity in the Serpentine River rose to a high of 65 mg/l (as CaC03) throughout the summer and early autumn; although this peak was coindicent with peak Chl-a values, pH values still increased at this time. Cole (1983) reports that if a water contains high amounts of Ca(HC03) 2 in equilibrium with C 0 2 , photosynthesis can shift the following equilibrium reaction to the right: C a ( H C 0 3 ) 2 <—> C a C 0 3 + H 2 0 + C 0 2 (3) This shift not only increases pH but also manifests itself by leaving calcareous incrustations on submerged objects such as plants. Although there was some indication of a positive correlation between peaks in pH and high Chl-a and high DO levels during this study, it is evident that photosynthesis is one of several factors contributing to fluctuating pH levels in the river. 5.1.1.4 Specific Conductance Specific Conductance along the length of the Serpentine is given in Figure 27; it is evident that the conductivity of the river increased in the floodplain. Specific conduc-61 SPECIFIC CONDUCTANCE ALONG SERPENTINE LENGTH O) ro o in 3 10 CN2 < W E-O i3 o o o E »—t o w Ul 550 500 450 -400 -350 300 250 200 150 SITE 176 - 1 1 — JUL 14 AUG 04 i i i SEP 01 SEP 29 i 1 1 1 t I OCT 27 NOV 24 Figure 27. Specific Conductance Along Serpentine Length, Sites 176, FH, & 152. 5.0 RESULTS AND DISCUSSION tance/depth profiles at Site 152 showed very clearly that, on occasion, a wedge of salt water can migrate up the river past Site 152. Figure 28 shows a marked increase in conductivity below the 1.0 m depth. Site #10 also has conductivity which increases with depth, but this is likely not due to salt water from the ocean, but possibly from farmland runoff containing salts (Figure 29). 5.1.1.5 Total Organic Carbon and Chemical Oxygen Demand Organic-C is a good indicator of the presence of animal wastes in the water column (North Carolina State Univ, 1971), although waters high in algae biomass will also exhibit Org-C. Among all 5 sampling stations along the length of the river, TOC normally ranged between 5 and 15 mg/l as C. There was a general increase in TOC following the 27 mm of rain which fell between Oct 28 and 31. Although relatively constant near 8 mg/l (as C) during the early autumn, the highest peak of Org-C at Site 176 occurred on Nov 17 after levels had risen steadily for 3 consecutive weeks (Figure 30). Sites 80 and FH also had peak concentrations on Nov 17. River TOC levels seem to increase following precipitation events of roughly 20 mm or more (Figures 10, 11). Most TOC seems to have been flushed from the upper watershed from Nov 10 to 15, when there was 84 mm of precipitation. In the week following, a further 71 mm of rain reduced TOC at all of Sites 176, FH, and 152 by 35 %. A similar pattern was observed by Bourque and Hebert (1982) during autumn flushing rains. In the lower Serpentine, TOC was less variable and with one exception TOC remained between 7.3 and 16.6 mg/l (as C) for the entire late summer and autumn (Figure 31). On Oct 13, Site #10 recorded a TOC of 27.4 mg/l as C. This event can only be explained by similar increases in COD, Org-N, Chl-a, and a DO saturation of 175%, which indicate that a very high concentration of viable algae was present. One explanation for this isolated occurrence could be that a farm drainage ditch in this 63 CONDUCTIVITY/DEPTH PROFILE AT SITE 152 s N S OCT 27 NOV 03 NOV 10 NOV 17 1 1 1 1 1 1 0 1000 2000 3000 4000 5000 6000 7000 SPECIFIC CONDUCTANCE AT 25 ° C ( u S / c m ) Figure 28. Specific Conductance/Depth Profile at Site 152. CONDUCTIVITY/DEPTH PROFILE AT SITE #10 o 0.4 -0.8 -1.2 -1.6 -2 -2.4 OCT 27 NOV 03 NOV 10 NOV 17 0 100 200 300 400 SPECIFIC CONDUCTANCE AT 25 ° C ( u S / c m ) Figure 29. Specific Conductance/Depth Profile at Site #10. 500 TOC IN UPPER SERPENTINE > i — i — i — i — i — i — i — I — i — i — i — i — i — i — i — i — i — i — i — i — i JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 Figure 30. Total Organic Carbon in Upper Serpentine, Sites 176, 80 & FH. Figure 31. Total Organic Carbon in Lower Serpentine, Sites #10 & 152. 5.0 RESULTS AND DISCUSSION vicinity was pumped out in an attempt to minimize potential flood risk by reducing ditch levels prior to the heavy autumn rains. Chemical oxygen demand (COD) results are far more varied than TOC. Interferences with NH3 and NO2" during the COD test may have contributed; however, even these occurrences cannot completely explain the highly variable results. Mercuric chloride was used to prevent CI" interferences as mentioned previously. COD results from this study can only add to Town's conclusions (1986): "the the-oretical relationship of COD to TOC, at 2.67 : 1 , according to the equation: C + 0 2 -- > C 0 2 (4) was reasonably well maintained, in practice". 5.1.1.6 Nitrogen Ammonia is present in animal urine, and is an intermediate compound in the heterotrophic bacterial breakdown of organic nitrogen wastes. As was noted by Town (1986), it appears that the bulk of the ammonia was entering the river upstream of Site FH (Figure 32). Until Oct 27, the highest total ammonia values were observed at Site 176, where they averaged over 0.3 mg/l (as N) throughout the summer. There are several small farms upstream of Site 176 at the edge of the uplands, (in the vicinity of 88 Ave and 176 St) and it appears that ammonia from the animal wastes is making its way into the river; septic tank and tile field seepage may also contribute. Site 176 is only 2 km downstream, and the river's velocity is typically 0.5 m/s at this point, allowing little time for oxidation of ammonia upstream of Site 176. Latimer Creek contributes additional ammonia to the system; N H 3 levels averaged 1.6 times that of the river at Site 176 for the duration of the study. As mentioned by Town (1986) ammonia in aqueous solutions forms ammonium ions, and an equilibrium is reached as shown: N H 3 + H 2 0 <--> N H 4 + + OH - (5) 68 Figure 32. Total Ammonia Along Serpentine Length, Sites 176, FH, & 152. 5.0 RESULTS AND DISCUSSION Ammonia toxicity is related only to the un-ionized ammonia, and increases as pH and temperature increase. The US-EPA recommends 0.020 mg/l un-ionized NH3-N as a water quality criteria for the protection of fish. This results in limits on total ammonia which are given in Table 1. During the entire sampling period total-ammonia levels were never above the US-EPA recommended limits in the Serpentine River; however, both dairy farm ditches continually exceeded the limits. At Site 80 the river has slowed considerably and the likelihood of bacterial nitrification is higher. Bacteria of the genus Nitrosomonas. which carry out nitrification, must have aerobic conditions. Correlation coefficients (r) for a linear regression between DO and N H 3 at Sites 80, FH, #10, and 152 are -0.54, -0.62, -0.44, and -0.55 respectively. This suggests that the oxidation of ammonia appears to be stimulated by high levels of DO which are present during algal photosynthesis. Nitrates (NO x) are present in the Serpentine at levels between 0.1 and 1.0 mg/l (as N) during the summer months as illustrated in Figure 33. Their most likely source during the dry weather was nitrification of ammonia, and decomposition of organic matter. During the month of October, there was a slight increase in N O x levels throughout the entire river's length, likely the result of some algal die-off and decomposition. The heavy rainfall (84 mm) which occurred in the upper watershed from Nov 10 to 15 caused the major flush of nitrates from the watershed, with N O x levels averaging near 4.0 mg/l (as N) for roughly 2 weeks. By Dec 1, N O x levels in the upper watershed had peaked and were returning to normal levels while the river downstream (Site 152) still had not completely discharged the high nitrate flow. Organic-N is present in manure, and in cellular material in the water column. Figure 34 shows that throughout the entire study Site 176 had the lowest levels of Org-N (some of the early values are higher; this is most likely due to bottom sediments which were accidentally suspended in the collected water sample due to poor sampling techniques which were improved later). Normal levels of Org-N in the rest of 70 5.0 RESULTS AND DISCUSSION TABLE 1 Concentrations of Total Ammonia (NH 3 + NH4+, as N) Which Will Contain an Un-lonized Ammonia Concentration of 0.020 mg/l Under the Stated Conditions of Temperature and pH. (From Hellawell, 1986) TEMP fC) 6.0 6.5 7.0 7.5 pH VALUE 8.0 8.5 9.0 9.5 10.0 5 160 51 16 5.1 1.6 0.53 0.18 0.071 0.036 10 ' 110 34 11 3.4 1.1 0.36 0.13 0.054 0.031 15 73 23 7.3 2.3 0.75 0.25 0.09 0.043 0.027 20 50 16 5.1 1.6 0.52 0.18 0.07 0.036 0.025 25 35 11 3.5 1.1 0.37 0.13 0.06 0.031 0.024 30 25 7.9 2.5 0.81 0.27 0.10 0.05 0.028 0.022 At pH values above 8.0 the stated values may be too stringent 71 Figure 33. Total Nitrates Along Serpentine Length, Sites 176, FH, & 152. O R G - N ALONG S E R P E N T I N E L E N G T H CO a o 3 Z, W O O o 2.8 2.6 2.4 -2.2 -2 -1.8 1.6 -1.4 -1.2 -1 0.8 0.6 H 0.4 0.2 0 • SITE 176 + SITE FH o- o SITE 152 - i — i — r — r JUL 14 AUG 04 cn b m CO c q co > z D D CO O c CO CO o z n i i ^ i I i i I I 1 1 1 1— SEP 01 SEP 29 OCT 27 NOV 24 Figure 34. Organic Nitrogen Along Serpentine Length, Sites 176, FH, & 152. 5.0 RESULTS AND DISCUSSION the river were between 0.6 and 1.4 mg/l (as N); Site FH levels were well above this range on Sept 29 and Oct 06. The river was covered with an algal mat at this location, and on these two dates a sample containing some floes of algae was unavoidable. This is confirmed by very high concentrations of TOC, total-P, and Chl-a from the same sample. Town (1986) reported a negative correlation between Org-N and N O x and explained this effect as NOx being taken up by algae and converted into Org-N. Figure 35 illustrates this conversion again, particularly from Jul 28 to Sept 29 when the correlation coefficient (r) between Org-N and N O x was -0.61. Furthermore, a positive correlation between Org-N and Chl-a existed, with the coefficient (r) equal to +0.50. This lends further evidence to the link between algal proliferation and increases in Org-N, at the expense of NOx-5.1.1.7 Phosphorus Phosphorus likely enters the Serpentine River in runoff from animal wastes and fertilized fields; routine monitoring for ortho-phosphate (P0 4~ 3) and organic phosphorus in this study has shown this to be true. Ortho-P is the nutrient form most readily used by phytoplankton. Ortho-P levels in the river are shown graphically in Figure 36, and during the summer months have been observed to decrease as the water moves downstream. This is probably due to P 0 4 " 3 uptake by algae in the slow-moving floodplain regions of the river downstream of Site 80. Site 176 recorded P 0 4 " 3 concentrations between 0.16 and 0.26 mg/l (as P) during the autumn. Site FH levels, near 0.08 mg/l (as P) throughout the summer, exhibited a marked increase to 0.21 mg/l on Sept 29, where it remained for four weeks. The reason for this increase is not clear. It may be simply that the algae's utilization of P 0 4 " 3 was declining as the viable population of algae began to diminish, or the death and decay of some algae may have released some P 0 4 " 3 . A less likely 74 5.0 RESULTS AND DISCUSSION 75 PO r 3 ALONG SERPENTINE L E N G T H -si CD O s u o o 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 SITE 176 SITE FH SITE 152 cn b CO c CO > o g CO o c CO CO O ^ I I I JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 Figure 36. Ortho-Phosphate Along Serpentine Length, Sites 176, FH, & 152. 5.0 RESULTS AND DISCUSSION possibility is that the bottom sediments became anaerobic, and some iron-hydroxy complexes were reduced resulting in the release of P 0 4 ~ 3 into the water column. (Surface DO was only 3.1 mg/l at Site 80 on Sept 29; however, DO at the water/sediment interface was not measured.) In any case, the onset of rain at the end of October again lowered P 0 4 " 3 levels in the river. Some of the P 0 4 " 3 likely precipitated with particulates and some was no doubt flushed from the river system. Total phosphorus levels at Sites 176 and FH are typically near 0.3 mg/l (as P) and are higher than those of the lower watershed (Figure 37). The increased algae growth which occurs between Sites 176 and FH amounts to a conversion of P 0 4 " 3 to Org-P with no net change in overall P levels. Site 152 levels average 0.13 mg/l (as P), which indicates that several processes may be at work to reduce P as the river flows downstream. Dilution of P levels may be occurring from the inflow from Mahood and Hyland Creeks, which are known historically to have low P levels, normally less than 0.05 mg/l as P (Bourque and Hebert, 1982). Sedimentation of P may also have occurred along the river's length, and a small utilization of P by benthic algae in the riparian zone is possible. Because total-P levels rarely drop below 0.1 mg/l (as P) (and most of this total-P is available as P 0 4 " 3 ) , it does not appear that phosphorus is at any time a limiting nutrient in the Serpentine system. 5.1.2 Water Quality in Drainage Ditches and Latimer Creek 5.1.2.1 Dissolved Oxygen (DO) Dissolved oxygen in both Dairy Ditch 1 and Harvie Rd Ditch was rarely above 35% of saturation, and more commonly averaged roughly 24% saturation (Figure 38). This is evidence that there was organic material in the ditch which was demanding oxygen. Latimer Creek has DO conditions which are similar to those at Site 176 of the mainstem of the Serpentine. Dissolved oxygen was never over 90% saturation, and never below 71% at the Latimer U/S and Latimer D/S sampling locations. There was a 77 Figure 37. Total-Phosphorus Along Serpentine Length, Sites 176, FH, & 152. cn DISSOLVED OXYGEN SATURATION CO o 1—4 fr* < te P f-< CO fr* H O te W CM 120% 110% -\ 100% 90% H 80% 70% -60% -50% -40% -30% -20% -10% -• LATIMER U / S •+ LATIMER D / S DAIRY DITCH 1 A * HARVIE RD DITCH i i i r 14 AUG 04 SEP 01 i i i r SEP 29 31 m co c CO > z o g CO o c CO CO O OCT 27 NOV 24 Figure 38. Dissolved Oxygen Saturation in Dairy Ditches and Latimer Creek. 5.0 RESULTS AND DISCUSSION 3 week slight depression in DO in both Latimer Creek and the drainage ditches beginning on Nov 03; this is due to the rains of late October which flushed the entire upper watershed. Chlorophyll-a levels indicate that algae were more prolific in the Harvie Rd Ditch (Figure 39). Water from this ditch was usually a very soupy green colour, and left a definite green slime layer on sampling equipment. The water in Dairy Ditch 1, however, was tea coloured, probably due to leachates from the soil which contains large amounts of peat (Sprout and Kelley, 1961). This yellow-brown colour is often indicative of dissolved humic substances (polymeric substances derived mostly from plant matter) which are very resistant to decay and reduce light penetration (Cole, 1983). Floating duckweed (Lemna) was prevalent in Dairy Ditch 1 in lieu of high levels of algae. Algae may have been inhibited by reduced light levels caused by the floating duckweed and also by high levels of ammonia, which can be toxic to phytoplankton (Duffer, 1971). Each of the two dairy ditch systems appears to have some oxygen contribution from photosynthetic activity, which prevent the systems from becoming completely anaerobic. 5.1.2.2 Temperature Temperatures in the dairy ditches through the summer and autumn were consistently higher than those in Latimer Creek (Figure 40). This is not surprising since Latimer Creek is primarily groundwater fed from the uplands on the eastern side of the watershed. Because the dairy ditches were usually stagnant, their temperatures warmed during the heat of the day, and consequently ditch temperatures were frequently above the mean daily air temperatures shown in Figure 25. Temperatures in Harvie Rd Ditch remained below those in Dairy Ditch 1 throughout the summer primarily because the Harvie Rd Ditch is closer to the uplands on the east side of the valley and so would receive an inflow of cool groundwater. 80 C H L O R O P H Y L L - A IN DAIRY DITCHES <• o DAIRY DITCH 1 A A HARVIE RD DITCH A A.... ...A-"A"' A"" ' / I I ...A / , A ' A "I I I I I I I I I I I I 1 1 1 1 1 1 1 1 — JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 Figure 39. Chlorophyll-a Levels in Dairy Ditches. TEMPERATURE IN DITCHES & LATIMER CRK JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 Figure 40. Temperatures in Dairy Ditches and Latimer Creek. 5.0 RESULTS AND DISCUSSION 5.1.2.3 p_H pH in the two dairy ditches during the summer was usually slightly higher than that of Latimer Creek and ranged from 6.8 to 8.9 as shown in Figure 41. This remained true during the autumn except after the 84 mm accumulation of rain between Nov 10 to 15; this reduced the pH of the Harvie Rd Ditch to roughly 4.5 for Nov 17 and 24. The alkalinity (to pH 4.5) of Dairy Ditch 1 water was measured once on Sept 8, and found to be 356 mg/l as C a C 0 3 , but Cole (1983) points out that for waters "rich in humic acids, the occurrence of humates precludes that valid conversion of alkalinity titrations to carbonate". As in the river itself, it appears that fluctuations in the pH of ditch waters are caused by a combination of alkaline fertilizers, rainfall, and photosynthesis. 5.1.2.4 Specific Conductance Specific conductance of the dairy ditches is given in Figure 42. Dairy Ditch 1 exhibited a steady conductivity, peaking slightly at Aug 17 and again at Nov 03 just following the initial autumn rains, before decreasing as the watershed is flushed. Conductivity of the Harvie Rd Ditch is far more variable, with a upward trend persisting through the entire summer and autumn. The author is unable to explain why conductivity exhibited different seasonal trends in the two ditches. 5.1.2.5 Total Organic Carbon Organic-C in both Dairy Ditch 1 and Harvie Rd Ditch fluctuated wildly between 50 and 183 mg/l (as C) during the course of the study (Figure 43); wet weather increased TOC levels by washing organic material into the ditches. Organic-C in both dairy ditches declined during August to a steady low of roughly 60 mg/l (as C) by Aug 25 where it remained relatively constant until Oct 13. The ditches appeared to function as shallow sewage oxidation lagoons during the summer (with an aerobic photosynthetic zone on the top, and an anaerobic zone on the bottom), reducing the 83 pH IN DAIRY DITCHES AND LATIMER C R E E K • • LATIMER U / S + - + DAIRY DITCH 1 <y o HARVIE RD DITCH t i — i 1 1 — i — i 1 — I — i — i — i 1—i 1 1 1 1 1 1 1 1 JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 Figure 41. pH in Dairy Ditches and Latimer Creek. SPECIFIC CONDUCTANCE IN DAIRY DITCHES 3000 2000 1000 • • DAIRY DITCH 1 -+ - + HARVIE RD DITCH -..+' +•'' n~-m—•—i - ^ / " — " + \ +' H ,+•.. / "-•4--1 1 1 ' — i — i — i h ..-*r •+-1 1 1 1 1 \ 1 1 1 1 r 1 V I i I I I I I I I I I 1 I I I 1 1 1 1 1 1 JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 Figure 42. Specific Conductance in Dairy Ditches. Figure 43. Total Organic Carbon in Dairy Ditches. 5.0 RESULTS AND DISCUSSION more readily degradable TOC until a level of roughly 60 mg/l (as C) was reached, beyond which further digestion practically ceased. Viable algae likely represent a large portion of the TOC in both the Dairy Ditch 1 and Harvie Rd Ditch systems, because the pattern of TOC and Chl-a (Figure 39) levels have correlation coefficients (r) of +0.70 and +0.89 respectively. After Nov 10 the heavy rains rendered the TOC levels in the ditches extremely variable. Ratios of COD : TOC (as C) for both Dairy Ditch 1 and Harvie Rd Ditch were found to be very near the predicted value of 2.67 (as discussed in Section 5.1.1.5) throughout the sampling program. TOC in Latimer Creek is given together with Nitrogen Forms in Figure 44. 5.1.2.6 Nitrogen Both Dairy Ditch 1 and the Harvie Rd Ditch had high levels of ammonia nitrogen, indicating that the rate of ammonia nitrification was substantially slower than the inflow of ammonia. In Dairy Ditch 1 total ammonia varied from 33.6 to 13.2 mg/l (as N) during the summer, with decreasing concentrations throughout the autumn until mid October (Figure 45). The Harvie Rd Ditch showed a very different pattern (Figure 46); ammonia remained near 25 mg/l (as N) during the summer and increased to levels of 80 mg/l (as N) prior to the heavy autumn rains. Ammonia in Latimer Creek reached 1.0 mg/l (as N) at times, and was all found to be coming from Dairy Ditch 1, as shown in Figure 47. Nitrates (NO x) in the Dairy Ditches could be present as a result of nitrification of ammonia, or drainage from fields fertilized with chemicals or manure. However, denitrification of nitrates would convert N O x to nitrogen gas which would then be lost to the atmosphere. Although the presence of algae in the dairy ditches means that there is some photosynthetic oxygen produced, DO conditions in the ditches are normally poor. This favours denitrification over nitrification, since the Nitrosomonas bacteria (which carry out the latter process) prefer an aerobic environment. This may 87 CO 00 I a o NITROGEN FORMS AND TOC IN LATIMER C R E E K 4.5 4 3.5 2.5 2 H o 1.5 0.5 0 NX • • TOC + + NOx * o ORG-N s \ ~~1 1 1 1 1 1 1 I 1 1 1 I 1 1 T 1 1 1 1 JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 26 24 22 20 18 16 14 12 10 8 6 4 2 0 O O E-cn b 33 m CO c CO > o g CO o a. CO CO o Figure 44. Nitrogen Forms and Total Organic Carbon in Latimer Creek. Figure 45. Nitrogen Forms at Dairy Ditch 1. NITROGEN FORMS AT HARVIE RD DITCH CD O 1st O K O CO 90 80 H 70 60 -50 -40 30 20 10 • • NOx + - + " N H 3 o o ORG-N 0 JUL 14 AUG 04 15 14 13 12 11 10 9 t- 7 8 ^ SEP 01 6 & 5 4 3 2 1 0 b CO c CO > z o g CO o c CO CO O SEP 29 OCT 27 NOV 24 Figure 46. Nitrogen Forms at Harvie Rd Ditch. CD O HH 3 W U O 1.1 1 0.9 -0.8 - : 0.7 0.6 H 0.5 0.4 H 0.3 0.2 -0.1 -0 N H 3 ON LATIMER CREEK + + • LATIMER U / S LATIMER D / S + +• + + i 1 1 r JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 cn b 33 m CO c CO > z o D CO O c CO CO O z Figure 47. Total Ammonia on Latimer Creek, Latimer U/S & D/S of Dairy Ditch 1. 5.0 RESULTS AND DISCUSSION explain why N H 3 levels remained high and N O x was low throughout the summer and autumn. Another possible explanation for poor nitrification is that there may have been a substance in the ditch water which was toxic to the nitrifying bacteria. Many metals have been shown to have inhibitory effects on microorganism populations, especially under shock loading (Kouzeli-Katsiri et al., 1987); this could occur during heavy storm events (Hall and Anderson, 1987). Concentrations of NOx ' n D o t n ditches reached almost 14 mg/l (as N) when the heavy rains of early November were sufficient to leach large quantities of soluble nitrates from the animal feed areas and fields. Latimer Creek had high N O x con-centrations (4 mg/l as N) during the same period (Figure 44). 5.1.2.7 Phosphorus Figure 48 indicates that in both dairy ditches the non P 0 4 " 3 fraction of the total-P was usually very small. However, with P 0 4 " 3 levels as high as 13.0 mg/l (as P) in Dairy Ditch 1, it appears that P 0 4 " 3 is not being adsorbed to solids, or precipitating with iron, aluminum, or calcium. Low oxygen levels in the ditches throughout the study period could be responsible for this (Henderson-Sellers and Markland, 1987) if the ditch chemistry is similar to conditions that can occur at the sediment/water interface of a deep eutrophic lake. Ortho-P levels in Dairy Ditch 1 gradually fell to 5 mg/l (as P) during the autumn until some rain at the end of October returned them to 9 mg/l (as P). By Nov 17, though, following heavy accumulations of rain, total-P was down to 1.2 mg/l (as P), its lowest levels throughout the study. The same was true for the Harvie Rd Ditch, except total-P was more variable and tended to increase during the autumn. Phosphorus concentrations in Latimer Creek are highly variable, but they confirm a high degree of contamination from Dairy Ditch 1 at all times (Figure 49). 92 PHOSPHORUS FORMS j - i — i — i — I — i — i — i — i — i — i — i — I — i — i — i — I — i — i — i — i — = r JUL 14 AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 Figure 48. Phosphorus Forms at Dairy Ditch 1 and Harvie Rd Ditch. PHOSPHORUS FORMS 0.6 0.5 0.4 -0.3 -0.2 -0.1 -0 ••o TOTAL-P LATIMER U / S - • PO 7 3 LATIMER U / S A A A TOTAL-P LATIMER D / S -+ PO 7 L A T I M E R D / S , A: i — i— r — OCT 27 NOV 24 i i ~ JUL 14 AUG 04 SEP 01 SEP 29 Figure 49. Phosphorus Forms at Latimer Creek, U/S & D/S of Dairy Ditch 1. 5.0 RESULTS AND DISCUSSION 5.2 Effects of Dairy Farm Drainage on Water Quality The fish kill of Oct 2, 1980 was attributed to an outflow of oxygen demanding water from Latimer Creek which allegedly occurred after a heavy rainfall. A dairy farmer had spread manure on fields which drain into the creek just prior to the rainfall (Moore, 1984). However, data collected from this study (Appendix I) and Moore (1984) suggests that the water quality of Latimer Creek is similar to that of the upper Serpentine at their confluence. The Serpentine River is relatively rich in nutrients such as N O x and P 0 4 ~ 3 , with concentrations typically averaging 0.64 mg/l (as N) and 0.18 mg/l (as P) respectively. This is similar to Latimer Creek waters which are 1.61 mg/l for N O x (as N) and 0.05 mg/l for P 0 4 " 3 (as P). The majority of the P 0 4 " 3 seems to come from the river itself, upstream of Site 176. Moore (1986) reports that the potential pollutional sources upstream of Site 176 include several hobby farms, pastured cattle with river access, effluent from the Bakerview trout farm, and wood waste fill. From these sources, there is more than enough P 0 4 " 3 to support a heavy summer algal bloom in the stagnant waters of the Serpentine's upper floodplain. Phosphorus input loads for the Serpentine river are not known; consequently an input-output P model cannot accurately be used to predict the river's trophic state. Chlorophyll-a and total-P concentrations have been used as a direct indication, however, and Figure 50 (from Henderson-Sellers and Markland, 1987) summarizes the trophic boundaries. Using this guide, the floodplain of the Serpentine River, where total-P varies between 0.1 and 0.5 mg/l (as P) and Chl-a varies between 10 and 311 ug/l, can be classified as eutrophic (and more likely hypertrophic) for part of the year. Agricultural drainage may also contribute a long-term BOD in the Serpentine River. River retention times during the autumn have been shown to be sufficiently long that nitrification of ammonia and Org-N could be exerting an substantial oxygen demand in river waters before these waters empty into Mud Bay. As in a laboratory 95 RESULTS AND DISCUSSION I 10 100 Mean chlorophyl ls ( mg m~~ ) 1 10 100 Maximum chlorophyll 3 (mg m~ 3 ) Figure 50. Chlorophyll-a Concentration as a Direct Indication of Trophic Boundaries. . j , (From Henderson-Sellers and Markland, 1987) 96 5.0 RESULTS AND DISCUSSION BOD test, after oxidation of the more readily biodegradable organic carbon wastes, nitrogenous wastes begin to exert an oxygen demand to bring about their oxidation. According to Klein (1966), ultimate oxygen demand (UOD) can be predicted by the stoichiometry equation: UOD (mg/l) = 2.67*(Org-C as C) + 4.57*(Tot-NH3 + Org-N, as N) (6) Table 2 shows the UOD of the two dairy ditches as well as for Sites 176, FH, and 152 on the Serpentine River itself. It is evident that if the total ammonia load present in the two ditches is typical of the water leaving drainage ditches from all dairy farms, oxygen levels in the river could be severely depressed following a heavy rainfall event. 5.3 Effect of Rainfall and Tidal Cycle on Water Levels and Water Quality "Agricultural drainage discharges and water temperature, as well as rainfall and river flow patterns, appear to contribute to fish kill conditions" (Moore, 1984). Rainfall, evaporation, pumping for irrigation, irrigation return inflow, and groundwater storage all interact to determine the net inflow of water into the Serpentine. Although it would be very difficult to quantify an entire water budget for the river during the summer months, the net result of all these factors can be seen in the water level recorders at Sites FH and #10. Strip charts from these recorders indicate that the tidal gates often remain closed for periods as long as ten days during the summer, and that the river levels increase very slowly over that time. Oct 12 to 22, for example, saw the river level rise only 0.6 m (Table 3) during that ten day closure of the tidal gates. The retention time of water in the river system is obviously high during such periods of warm weather and low precipitation; some possible consequences have been discussed above. A low flow rate in the upper floodplain contributes to the buildup of nutrients and the proliferation of surface algal mats. The river's stagnant nature also permits settling of suspended solids; density stratification due to water temperature and salinity were observed at Site 152. 97 5.0 RESULTS AND DISCUSSION TABLE 2 Ultimate Oxygen Demand (UOD) for selected sites on Serpentine River, and also for Dairy Ditches and Latimer Creek D/S.* SAMPLING SITE AUG 04 SEP 01 SEP 29 OCT 27 NOV 24 SITE 176 58.9 22.2 21.0 22.0 42.3 SITE FH 56.4 25.4 99.6 33.7 54.0 SITE 152 35.7 38.7 29.7 41.3 , 40.7 LATIMER D/S 26.4 26.4 26.7 43.7 • 49.6 DAIRY DITCH 1 466 298 267 258 257 HARVIE RD DITCH 312 316 338 664 340 * Values Expressed as mg/l Oxygen UOD = 2.67 * TOC(mg/l as C) + 4.57 * (NH3 + Org-N) (mg/l as N) (From Klein, 1966) 98 5.0 RESULTS AND DISCUSSION TABLE 3 Serpentine River Levels (m) as Recorded by Recorders on Bridges at Sites FH, #10, and also on Latimer Creek at 188th Street. Three time intervals are given for comparison: SEP 3-15, OCT 10-25, and NOV 21-28 SERPENTINE, SITE FH SERPENTINE, SITE #10 LATIMER CREEK DATE DEPTH TIME DEPTH TIME DEPTH TIME (m) (hrs) (m) (hrs) (m) (hrs) SEP 03 1.55 800 1.6 700 1.15 1030 1.2 1000 SEP 04 1.35 930 1.35 900 1.0 1100 0.95 1000 SEP 05 1.1 1100 1.1 1030 0.95 1300 0.95 1200 SEP 13 1.5 430 1.5 400 1.4 600 1.4 500 SEP 14 1.5 530 1.55 500 1.4 700 1.45 600 SEP 15 1.65 600 1.65 500 1.5 800 1.55 ; 600 OCT 10 1.45 230 1.5 200 1.25 500 1.3 400 OCT 11 1.35 300 0 1.25 500 OCT 22 1.85 1.9 0 1.7 130 1.7 200 OCT 23 1.8 0 1.8 0 1.5 300 1.55 200 OCT 24 1.65 100 1.65 0 1.3 300 1.3 300 OCT 25 1.4 130 1.4 100 1.1 430 1.15 400 NOV 21 1.35 200 1.3 200 1.6 1900 ; 1.65 1900 0.0 1900 2.55 2400 2.2 2200 NOV 22 2.35 200 1.95 200 1.95 100 0.4 1000 3.1 1900 3.1 2100 0.7 1500 NOV 23 1.9 300 1.7 300 0.15 1800 2.7 2330 2.65 2200 0.55 2100 NOV 24 2.0 400 1.75 300 0.45 1500 3.05 2230 3.0 2200 0.9 1900 NOV 25 1.9 630 1.7 500 0.25 1300 2.4 2300 NOV 26 2.4 0 0.1 200 1.55 700 1.4 500 NOV 27 2.0 200 1.95 200 1.5 600 1.4 530 NOV 28 1.85 400 1.85 400 1.55 600 1.5 600 99 5.0 RESULTS AND DISCUSSION Precipitation serves to flush waste material into the river. Rainfall washes manure from feed areas, pastures, and fields, and then drains into the lowland ditches. The ditches respond to increased inflow by overflowing into natural creeks, and into the river itself. Results from this study indicate that concentrations of TOC, N H 3 , NOx, and total-P in the river increase after precipitation events of 20 mm or more (one such event occurred on Jul 30 and 31, and the resulting pollutional effects were detected on Aug 04). In addition, pH and temperature were both lowered following rainfall. Urban storm water runoff is also known to contribute large amounts of BOD (Singh et al., 1979). 5.4 Assessment of Aeration System The aerator was designed to reaerate the river during a severe DO deficit, but it was not well tested during Town's 1985 research. Although the aeration system was operating full-time beginning on Oct 15 in case a severe drop in DO occurred, the system was not fully tested because a faulty hydrolab at Site 152 failed to collect any meaningful data during the entire study. 5.4.1 Tidal Effects and Flow Patterns in the Aeration Zone Results from a continuous-monitoring YSI DO probe and strip chart installed 100 m downstream of the aerator are shown in Figures 51, and 52. Because the ocean tides were not low enough to open the tidal gates during this four day period, the river was not flowing past the aerator, and the two DO traces do little to shed light on the aerator's performance. The lower DO values at the aerator site suggest the possibility that the diffused air supply may even be stripping supersaturated DO from the water column. This hypothesis is supported by DO conditions measured at Site #10, which indicate that supersaturation frequently occurred during the period of Oct 16 to 18 when DO was greater than roughly 11.4 mg/l. (Dissolved oxygen saturation at a 100 DO AND WATER LEVELS VS TIME » OCEAN TIDE LEVEL A — A LEVEL AT SITE F H * v LEVEL AT SITE #10 1 i i 0 12 24 12 24 TIME (HOURS) Figure 51. Dissolved Oxygen and Water Levels vs Time, Oct 16 and 17. DO AND WATER LEVELS VS TIME o o OCEAN TIDE LEVEL A A LEVEL AT SITE FH v v LEVEL AT SITE #10 DO AT SITE #10 DO AT AERATOR SITE 0 12 24 12 24 TIME (HOURS) Figure 52. Dissolved Oxygen and Water Levels vs Time, Oct 18 and 19. 5.0 RESULTS AND DISCUSSION temperature of 10.0 °C and zero CI" content is 11.33 mg/l (Medcalf and Eddy, 1979).) It is more likely, however, that the turbulence caused by the bubble curtain mixes the river water and does not allow the algae near the surface to produce as much oxygen. Mixing of high DO surface waters with water from the river bottom (where the DO/depth profile is similar to those shown in Figures 13, and 14) would also lower DO measured on the surface, due to a mass balance of oxygen. Lower DO in the vicinity of the aerator were also found by Town (1986) when the aerator was first operated. Dissolved oxygen electrode systems (like those used in the portable YSI probe and the hydrolab) can give unreliable results when water is not moving past the gas-permeable membrane or also when water is moving too quickly past the membrane. This may explain why the DO levels often increased just at the time the river levels started to drop in response to a tidal gate opening. Figures 53, 54, and 55 all illustrate this phenomena. The last two figures also show the river's response to four consecutive days of rain which began with roughly 35 mm of rain on Nov 21. River levels increase dramatically, coinciding with an opening of the tidal gates, yielding an upswing in DO levels. Subsequent openings of the tidal gates are also accompanied by peak concentrations of DO. Figures 15, and 16, as discussed earlier give a picture of the DO levels along the river on a small collection of sampling days. Although DO spot checks were not done at the aerator site, it is evident that DO levels at Sites #10 and 152 (upstream and downstream) of the aerator can be similar (as in Figure 15) or very different (as in Figure 16). Again, though, they provide little indication of the aerator's performance irv situ because the river was not flowing through the aeration zone with the tidal gates closed on each of these dates. 103 DO AND WATER LEVELS VS TIME o » OCEAN TIDE LEVEL A A LEVEL AT SITE F H v v LEVEL AT SITE #10 i I 'H : — I : 1 0 12 " 24 12 24 TIME (HOURS) _ Figure 53. Dissolved Oxygen and Water Levels vs Time, Oct 22 and 23. DO AND WATER LEVELS VS TIME o cn OH W P P o p OCEAN TIDE LEVEL A LEVEL AT SITE FH v v LEVEL AT SITE #10 24 TIME (HOURS) cn m CO c CO > z D g CO o c CO CO O Figure 54. Dissolved Oxygen and Water Levels vs Time, Nov 21 and 22. DO AND WATER LEVELS VS TIME * o OCEAN TIDE LEVEL A A LEVEL AT SITE FH * v LEVEL AT SITE #10 0 12 24 12 24 TIME (HOURS) Figure 55. Dissolved Oxygen and Water Levels vs Time, Nov 23 and 24. 5.0 RESULTS AND DISCUSSION 5.4.2 Discussion of Past Aerator Assessments Data from spot DO readings taken by Town in 1985 are similar to this study. On one occasion (Sept 25,1985), however, Town recorded DO concentrations of 6.5 mg/l at Sites #10 and 152 when DO at the aeration zone was nearly 1 mg/l higher. The performance of the aerator is expected to increase with a large DO deficit, which increases the driving force to transfer oxygen from the air bubble to the water column. Even if DO in the lower Serpentine were to approach zero, it appears doubtful that the aerator would be able to maintain any beneficial DO downstream of the aeration zone because the tidal gates open so rarely. Without the gates open and the river actively flowing into Mud Bay, the river is stagnant. Dissolved oxygen added in the aeration zone would largely be confined to a reach of the river near the aeration zone and likely could not be measured at either Site #10 or Site 152. 5.4.3 Preventing Fish Kills At the present time it is not certain whether salmon or trout heading up-river on their spawning migration would postpone their migration if they encountered near lethal oxygen conditions. Davis (1975) cites research which suggests that juvenile Chinook salmon (Oncorhynchus tshawytscha) show some avoidance of DO levels of 1.5 - 4.5 mg/l, but adds that it does not appear to be a highly directed behavior. "It may result simply from increased locomotor activity with more random movement, which is satisfied by discovery of improved oxygen conditions" (Davis, 1975). Whether salmon driven by the need to spawn would congregate in an aerated portion of the river until DO levels upstream were safe is doubtful (Caverhill, 1987). Proposals to install a removable fish barrier at the upstream end of the aeration zone (Town, 1986) have not been implemented because of fears that floating debris could create maintenance problems. A removable fish barrier at the upstream end of the aeration system remains the easiest and least expensive improvement to the aeration system. 107 5.0 RESULTS AND DISCUSSION Aeration was viewed as a band-aid approach to the low DO problems that the Serpentine River has been undergoing in recent years (Moore, 1984). However, it is doubtful (based on the performance of this single aerator) that it would be effective at saving fish in the event of a severe DO problem on the river. The necessary course of action now appears to be the implementation of clean-up of agricultural nutrient discharges which are leading to the proliferation of algae. This would lower the total-P loading to the river, and reduce the danger of ammonia levels becoming toxic to fish, as well. Over the short term, harvesting of filamentous algae blooms should be seriously considered. 108 6.0 DISCUSSION OF SELECTIVE PAST WATER QUALITY FINDINGS 6.1 Phytoplankton Populations Previous research (Town, 1986) indicated a rapid algal die-off which had occurred by October 15 and was likely due to a lack of sunlight. The mean number of sunlight hours per day (as recorded by Atmospheric Environment Services) for the two weeks prior to Oct 7 was 7.6 hours, but for the week prior to Oct 15 it was only 2.2 hours. The predominant phytoplankton, as classified by Moore (1984) were Bacillariophvceae (diatoms) and Cyanophyceae (blue-green algae). Cole (1983) states that for lakes in northern temperate regions: "a common annual cycle of the phytoplankters is a spring bloom of diatoms, followed by a summertime blue-green predominance, and a second diatom bloom in late fall. In eutrophic lakes...the filamentous diatoms Melosira. and Stephanodiscus (similar to Cvclotella) appear first. Then with agricultural runoff or increased eutrophication ... Asterionella appears. ...Later another diatom, Fragilaria. shows up, particularly if sewage enters the lake." Moore's work from June 15 to Oct 17, 1983 specifically identified the diatoms Cyclotella. Stephanodiscus. Melosira. and Fragilaria. Moore (1984) also identified the heavy surface mats of algae as Hydrodictyon spp. Cole (1983) reminds us that "it is the species and not the genus which serves to indicate water quality", because generic designations are not always accurate. Nevertheless, Moore's findings do correspond well with Cole's descriptions of the types of organisms in eutrophic waters. Bourque and Hebert (1982) also found these diatoms in 1974-75, but they were not as numerous as Meridion circulare. Algal primary productivity was also reported by Town, and was for the most part found to correlate with Chl-a levels as long as temperature effects were taken into consideration. Later in the autumn when temperatures were cooler and the hours of daylight were shorter, primary productivity dropped. Town, however, was wise to add 109 6.0 DISCUSSION OF SELECTIVE PAST WATER QUALITY FINDINGS that some species of algae, though they are physically much smaller than other species, can contribute a large portion of the total primary productivity even though they may be a small fraction of the total algal community biomass. Primary productivity decreased with increasing depth, likely due to high turbidity (subjectively observed) which reduced light penetration. 6.2 Sediments Moore sampled sediments once during the summers of 1981 and 82, and a total of nine dates throughout the summer of 1983. Total organic carbon, TKN, and total-P were not found to be accumulating over time (Town, 1986). Using in-situ respiration chambers, Duncan (1986) found that the DO demand from river sediments was low. In fact, at Site FH in Oct 1986 Duncan measured a net oxygen production of 0.1 g 02/m^/hr from benthic algae. The reader is reminded that the river's depth at Site FH is often less than 1.0 m (Section 4.2); because light penetration is very low beyond the upper 1 m, photosynthetic oxygen production from sediments is unlikely downstream of Site FH because the river is deeper. However, it appears from Duncan's results that the oxygen demand exerted by sediment in the Serpentine River is not excessive. The benthic oxygen demand in the Harvie Rd Ditch, however, was 0.1 g 0 2 / m 2 / h r . Trace metals in the Serpentine were also analyzed by Moore, and discussed at length in Town's thesis. He concluded that the Serpentine, when compared to 300 other sediments samples from lower Fraser Valley streams, would not be classified as contaminated with trace metals (there were no metals which had values higher than two standard deviations larger than the arithmetic mean). 110 6.0 DISCUSSION OF SELECTIVE PAST WATER QUALITY FINDINGS 6.3 Low Dissolved Oxygen Levels and Rainfall The link between rainfall and ensuing fish kills has been well explored in past studies on the Serpentine, and for a very deserving reason. Table 4, shows that in all five recorded kills there has been rainfall in the previous week, and that "in all cases except Oct 31, 1983, the two days just prior to the kill were fairly dry" (Town, 1986). Moore (1984) points out that rainfall patterns in the autumn of 1981 and 82 were not heavy first-flush events like those which caused major fish kills in 1980, 83 and 84. Autumn rains in 1981 and 82 gradually increased throughout the season, with fewer warm and dry periods between rainfall events. This is similar to the 1987 rainfall pattern observed in this study, which did not lead to a fish kill. As discussed in Section 5.1.1.1, the onset of rainfall on Oct 27, 1987 was followed by increasing amounts of rainfall almost daily. This pattern of rainfall leads to increasing flowrates in the river, and appears to be sufficient to flush organic material through the river system without it exerting a heavy oxygen demand. Rainy weather also precludes higher temperatures which would speed decay of organic material and this makes low dissolved oxygen conditions less likely. Urban runoff, although known to have a high BOD in first flush events (Novotny, 1985), likely contributes significant dilution to the river waters shortly thereafter. 111 DISCUSSION OF SELECTIVE PAST WATER QUALITY FINDINGS TABLE 4 Rainfall and Fish Kills (From Town, 1986) DATE FISH KILLED RAINFALL* (mm) Oct 2, 1980 300 - 800 19.6 Oct 9, 1983 50 14.0 Oct 31, 1983 150 49.6 Oct 19, 1984 12 10.9 Oct 28, 1984 470 41.6 * Rainfall in Previous 7 Days 112 7.0 CONCLUSIONS AND RECOMMENDATIONS 7.1 Conclusions 7.1.1 General (1) Dairy farms are a definite source of contaminants to the upper Serpentine River. The two dairy ditches studied in the upper watershed have high levels of TOC, which indicates that the most likely source of the contamination is attributable to animal wastes. This conclusion is supported by the high levels of N H 3 , N O x , Org-N, P 0 4 " 3 , and TP, found in these ditches. (2) Latimer Creek does not contribute as much contamination to the river as previously thought. Creek samples collected downstream of a dairy farm drainage ditch indicated that the water quality of the creek is comparable to that of the Serpentine River at their confluence. This is due to poor flushing of the ditch into the creek and substantial dilution of the ditch waters when blended with those of the creek. The deterioration in Serpentine River water quality downstream of Latimer Creek is mainly caused by a change in the hydraulic character of the river: the river widens and a decrease in water velocity results in stagnation. The increase in organic material downstream of Latimer Creek noted by previous researchers most likely occurs as microorganisms multiply and take advantage of stagnant waters and an abundance of nutrients. (3) A decrease in river Chl-a levels correlates well with a general depletion of DO and is accompanied by an increase in NH3 and N O x , first in the upper floodplain of the river, and progressing downstream during the month of October. This is evidence that the autumn algae die-off was occurring and that N H 3 released from algal decomposition was gradually being nitrified. The first major autumn rainfall occurred on Oct 30-31, which largely precluded the involvement of agricultural carbonaceous and NH3 drainage in the river during the month of October. 113 7.0 C O N C L U S I O N S A N D R E C O M M E N D A T I O N S (4) Heavy rainfall on Oct 30-31 flushed the watershed and overfilled ditches, causing them to drain into the river. Nitrates (NO x) showed a high correlation to heavy rainfall (similar to 1984 and 1985 data), but almost all pollutants in the river increased somewhat following large rainfall events. An initial increase in P 0 4 " 3 was quickly followed by a decrease to low levels, as a result of adsorption to particulate matter and sedimentation. (5) No fish kill occurred on the Serpentine River in the autumn of 1987. The best explanation for this appears to be that the occurrence of the autumn algae die-off and decay did not occur simultaneously with the first heavy autumn rains, which flush high BOD agricultural drainages into the Serpentine River. Instead, the rains arrived on Oct 30-31, three weeks after the initial decline in algal biomass had begun in the upper floodplain of the river. After the onset of autumn rains, the rain was relatively steady and temperatures remained cool for the entire month of November; this flushed the river of its high organic load and prevented the exertion of a large oxygen demand. (6) The aerator appears to be having a small reaeration effect during the autumn. The DO levels never fell to critical levels during the autumn of 1987, however, so the aerator's ability to add oxygen to the Serpentine during critical dissolved conditions has not yet been fully tested. (7) During periods of low precipitation the Serpentine River is very poorly flushed. During a ten day period from Oct 12 to 22 a water level recorder at Site #10 showed that river levels had risen only 6 cm/d, and that the tidal gates had not opened once during that time. 7.1.2 Specific (1) Of all 5 sampling sites on the Serpentine River, the river consistently exhibited the poorest water quality at 80th Avenue (Site 80). DO measurements dropped as low as 3.1 mg/l and never exhibited supersaturation as did Site FH. Chl-a 114 7.0 C O N C L U S I O N S A N D R E C O M M E N D A T I O N S concentrations are much lower at Site 80 indicating that the algae population increases as the river moves the 1.1 km distance to Site FH. With the river usually relatively stagnant in this upper floodplain region, there is adequate time between Site 80 and Site FH for algae growth. (2) Water temperatures in July and August were typically above 21 °C, as was the case during Town's research in 1985. Summer water temperatures remain a critical situation for the survival of coho fry. (3) A continuous-monitoring hydrolab detected a response to photosynthesis and respiration when installed at Site #10. (4) There is a high variance in river pH during the hot dry summer and autumn weather. The downstream regions of the river consistently have higher pH than upstream, as well as higher Chl-a levels. It appears that high rates of photosynthesis, while consuming CO2, shift the carbonate equilibrium such that H + ions are consumed. Even though the alkalinity of the Serpentine is highest in summer, the buffer system is insufficient to prevent the pH from rising. Heavy autumn rainfalls were observed to lower pH in the river, likely due to the acidity of the rainfall itself, and possibly from humic acids materials leaching from the peat soils in the floodplain. (5) Specific conductance/depth profiles show clearly that the tidal gates at Hwy 99A allow some saline water to penetrate the river system and create a salt wedge that can be detected at Site 152. The wedge can be as deep as 1.5 m at this location with conductivities typically near 6000 uS/cm. (6) Ammonia concentrations are very high in the dairy ditches, but nitrifiers seem to be unable to oxidize the ammonia because of low dissolved oxygen in the ditches. Higher oxygen levels in the river are permitting some nitrification, however; ammonia levels become lower downstream where the density of dairy farms is lower. There is a negative correlation in a linear regression between high DO and N H 3 throughout the river's length. 115 7.0 CONCLUSIONS AND RECOMMENDATIONS (7) Nitrates and org-N have a negative correlation in the lower reaches of the river during the summer and early autumn. It appears that N O x is converted into org-N during periods of algal proliferation, since the increase in org-N occurs together with an increase in Chl-a. This is similar to findings by Town in 1985. 7.2 Recommendations A five-year strategy for source control of farm animal wastes should be developed, and implementation begun. A single government department should be given this task, along with further identification of potential sources of nutrient enrich-ment in the upper Serpentine watershed. The pollutional levels in the river at Site 176 suggest that there are unidentified sources of contamination upstream from this point. A monitoring program to elucidate these sources should be implemented. By scaling-down ditch water quality analyses to TOC, total ammonia, P 0 4 " 3 , and fecal streptococci, sources of animal wastes could be pinpointed at less cost. All dairy farms, feed lots, and poultry farms within the watershed should be investigated by the Waste Management Branch, and visited on a regular basis. Manure storage facilities should be upgraded if required, and farmers educated to spread manure regularly, but to leave a buffer zone around ditches and natural drainage courses where no manure is spread. The problem of liquid manure must be addressed; liquid manure must be contained and spread on pasture away from any watercourses. Every effort should be made to carry out the above program with the farmers in an educational and consultative manner. Research in implementing new waste control measures on farms, as well as common sense, indicates that the voluntary coopera-tion of farmers with new methods is most likely to achieve the desired results. Dykes should be fenced off to animals and not used for grazing. Cattle should not have direct access to the river for drinking water. 116 7.0 C O N C L U S I O N S A N D R E C O M M E N D A T I O N S A program is needed to educate the public on the proper disposal of liquid wastes. The Tynehead Hatchery is currently distributing pamphlets door-to-door in the Serpentine watershed; these explain that many liquid household wastes can harm fish populations when poured into storm sewers. Painting fish on curbs next to roadside catch basins further identifies storm sewers as tributaries to waters containing fish. Similar programs are being done in North and West Vancouver to protect salmon streams. A clampdown on illegal dumping of solid wastes in the river is also desirable. Signs warning would-be dumpers of prosecution should be posted on a large number of the river's public access points, and these signs have a telephone number for the public to report offenses. Possible future research projects may include the feasibility of low maintenance, on-site treatment systems of liquid manure from dairy cows. Such a project may be carried out in cooperation with a farmer, and may prove to be the best approach to reducing nutrient loadings to the river. On-site chemical precipitation of PO4"3 using iron, calcium or aluminum should be explored together with this treatment scheme. By removing the large surface mats of filamentous algae which accumulate on the Serpentine River during the summer months, part of the BOD load induced on the river by the autumn algae die-off and decay could be reduced. The feasibility of any systems of algae harvesting in the shallow reaches of the river between Fraser Hwy and 64th Avenue should be investigated. Since the aeration system was installed in the lower Serpentine River in the summer of 1985, a critical dissolved oxygen deficit causing a fish kill has not occurred. It remains worthwhile to evaluate it's reaeration potential in a year where there is a significant dissolved oxygen deficit in the lower Serpentine River. 117 REFERENCES Amberg, H.R., Wise, D.W., and Aspitarte, T.R., (1969) "Aeration of Streams with Air and Molecular Oxygen", Tappi, Vol 52, No 10, p 1866. American Public Health Association (APHA), American Water Works Association (AWWA), Water Pollution Control Federation (WPCF), (1985) Standard Methods for the  Examination of Water and Wastewater. 16th ed. Atmospheric Environment Services (AES), (1987) Canadian Climate Normals, Environment Canada. Backman D.C., and Rithaler, J . , (1987) "Investigations of Downstream Migrations, Summer Residency, Adult Spawning and Stream Habitat for Juvenile Salmonids in the Nicomekl (and Serpentine) Rivers, BC. 1986." Prepared for Dept of Fisheries and Oceans, Public Involvement Program. Barker, J.C., (1973) "The Effects of Surface Irrigation with Dairy Manure Slurries on the Quality of Groundwater and Surface Runoff." Tennessee University of Knoxville. Department of Agric Eng. NTIS PB-226 917. Barker, J.C., Humenik, F.J., and Overcash, M.R., (1983) "Evaluating Swine Drylot Runoff Impact on a Coastal Plain Stream." North Carolina State Univ. at Raleigh. Dept. of Biol, and Agric. Eng. EPA-600/S2-83-079, Bathala, C.T., Khirod, C D . , and Jones, W.D., (1979) "Assimilative Capacity of Small Streams," Jour. Env. Eng. Div., Proc. ASCE, Vol 105, p 1049. Bergmann, LA., (1980) "Status Report August 1,1980, Serpentine - Nicomekl Studies and Projects," BC Min of Env, Assessment and Planning Dept. Bourque, S., and Hebert, G., (1982) "A Preliminary Assessment of Water Quality and Biota in the Serpentine and Nicomekl Rivers and Mahood Creek, 1974 -1975," BC Min of Env and EPS. Caverhill, P., (1987) Biologist, BC Min of Env, Fish and Wildlife Service, per comm. Chanlett, E.T., (1979) Environmental Protection. McGraw-Hill, New York, NY. Clark, B.C., and Truelson, R.B., (1977) "Serpentine/Nicomekl Study: First Drafts of Fisheries Work," Unpub Field Notes, BC Min of Env, Fish and Wildlife Br. Cole, G.A., (1983) Textbook of Limnology. The C.V. Mosby Company, St. Louis, Missouri. Cox, B., (1975) "The Effects on Fish, Wildlife, and Recreation as a result of Diking, Diversion, Drainage and Irrigation on the Serpentine - Nicomekl Floodplain," Unpub Draft, BC Min of Env, Fish and Wildlife Br. Cox, B., and McFarlane S., (1978) "Fish and Wildlife Resources of the Serpentine -Nicomekl Watershed," Unpub Interagency Draft, BC Min of Env, Fish and Wildlife Br. 118 Damaskos, S.D., and Papadopoulos, A.S., (1983) "A General Stochastic Model for Predicting BOD and DO in Streams." Intern. J . Environ. Studies, Vol 21, p 229. Davis, J.C., (1975) "Minimal Dissolved Oxygen Requirements of Aquatic Life with Emphasis on Canadian Species: A Review", J . Fish Res. Board Canada, Vol 32, No 12, p 2295. Devore, J.L., (1982) Probability and Statistics for Engineering and the Sciences. Brooks/Cole Publishing Company, Monterey, Cal. Dick, J.H., (1975) "Water Control in the Serpentine - Nicomekl Flood Plain: A Watershed Management Approach," BC Min of Env, Fish and Wildlife Br. Dickey, E.C., and Vanderholm, D.H., (1981) "Vegetative Filter Treatment of Livestock Feedlot Runoff." J . Environ. Qual., Vol 10, No 3, p 279. Dorich, R.A., Nelson, D.W., and Sommers, L.E., (1980) "Algal Availability of Sediment Phosphorus in Drainage Water of the Black Creek Watershed." J . Environ. Qual., Vol 9, No 4, p 557. Duff, J.H., Triska, F.J., and Oremland, R.S., (1984) "Denitrification Associated with Stream Periphyton: Chamber Estimates from Undisrupted Communities." J . Environ. Qual., Vol 13, No 4, p 514. Duffer, W.R., Kreis, R.D., and Harlin, C.C., (1971) "Effects of Feedlot Runoff on Water Quality of Impoundments", EPA Water Pollution Control Research Series 16080 GGP 07/71. Duncan, W.F.A., (1986) "Dissolved Oxygen Demand in the Serpentine River using In-Situ Test Chambers." SUTEK Environment Services, BC Min of Env, Waste Management Br. Finstein, M.S., Strom, P.R., and Matulewich, V.A., (1978) "Discussion of 'Significance of Nitrification in Stream Analysis-Effects on the Oxygen Balance' by R.J. Courchaine.", J . Water Poll. Control Fed., Vol 50, p 835. Hall, K.J., and Anderson, B.C., (1988) "The Toxicity and Chemical Composition of Urban Stormwater Runoff," Can. J . of Civil Eng, Vol 15, p 98. Hansen, W.H. et al., (1976) "Manure Harvesting Practices: Effects on Waste Characteristics and Runoff." Colorado State University., Fort Collins. NTIS PB-265 569 Hellawell, J.M., (1986) "Biological Indicators of Freshwater Pollution and Environmental  Management". Elsevier Applied Science Publishers, London. Henderson-Sellers, B., and Markland, H.R., (1987) Decaying Lakes--The Origins and  Control of Cultural Eutrophication. John Wiley and Sons, Chichester, Great Britain. Hirst, S.M., and Easthope, C.A., (1981) "Use of Agricultural Lands by Waterfowl in Southwestern British Columbia," J . Wildlife Management, Vol 45, No 2, p 454. Hollon, B.F., Owen, J.R., and Sewell, J.I., (1982) "Water Quality in a Stream Receiving Dairy Feedlot Runoff," J . Environ. Qual., Vol 11, No 1, p 5. 119 Humenik, F.J., Smolen, M.D., and Dressing, S.A., (1987) "Pollution from Nonpoint Sources," Environmental Science and Technology, Vol 21, No 8, p 737. Hutchinson, G.L., and Viets, F.G., (1969) "Nitrogen Enrichment of Surface Water by Absorption of Ammonia Volatilized from Cattle Feedlots," Science, Vol 166, p 524. Imhoff, K.R., and Albrect. D., (1978) "Instream Aeration in the Ruhr River," Prog. Wat. Tech., Great Britain, Vol 10, Nos 3 and 4, p 277. Kelman, S., et al., (1977) "Quality Aspects of Agricultural Runoff and Drainage." Jour. Irr. and Drain. Div., Proc. ASCE, Vol 103, p 475. Klein, L, (1966) River Pollution III: Control. Butterworth Publishers, London Eng. p 10. Kouzeli-Katziri, A., Kartsonas, N., and Priftis, A., (1988) "Assessment of the Toxicity of Heavy Metals to the Anaerobic Digestion of Sewage Sludge," Env Tech Letters, Vol 9, p261. Lake, J . , and Morrison, J . , (1977) "Environmental Impact of Land Use on Water Quality, Final Report on the Black Creek Project." Allen County Soil and Water Conservation District, Fort Wayne, Ind. EPA 905/9-77-007-B. Lee, Ming T., (1985) "A Methodology of Assessing Nonpoint Source Pollution from Agricultural Watersheds." Watershed Management in the Eighties. ASCE Irr. and Drain. Div. Conference, Denver, Colo. April 30,1985. p 191. Long, F.L (1979) "Runoff Water Quality as Affected by Surface-applied Dairy Cattle Manure." J . Environ. Qual., Vol 8, No 2, p 215. Lowrance, R.R., Todd, R.L, and Asmussen, L.E., (1984) "Nutrient Cycling in an Agricultural Watershed: II. Stream Flow and Artificial Drainage." J . Environ. Qual., Vol 13, No1,p27 . Lunin, J . , (1971) "Agricultural Wastes and Environmental Pollution," Advances in  Environmental Science and Technology." Edited by Pitts, J.N., and Metcalf, R.L, John Wiley & Sons, Inc. p215. Meadows, M.E., Weeter, D.W., and Green, J.M., (1978) "Assessing Nonpoint Water Quality for Small Streams." Jour. Env. Eng. Div., Proc. ASCE, Vol 104, p 1119. Metcalf and Eddy, Inc., (1979) Wastewater Engineering: Treatment/Disposal/Reuse. McGraw-Hill, New York, NY. Miner, J.R., Koelliker, J.K., and English, M.J., (1980) "Predicting Cattle Feedlot Runoff and Retention Basin Quality." Oregon State University, Department of Agric. Eng. NTIS PB81-113045. Moore, B., (1984) "Serpentine River Dissolved Oxygen Survey 1981 -1983." Unpub Report, BC Min of Env, Waste Management Br. National Topographic Series, (1977) Surveys and Mapping Branch, Ottawa, Ont. 120 North Carolina State University, Dept. of Biol, and Agric. Eng. (1971) "Role of Animal Waste in Agricultural Land Runoff." EPA Water Pollution Control Research Series 13020 DGX 08/71. Novotny, V., Sung, H., Bannerman, R., and Baum, K., (1985) "Estimating Nonpoint Pollution from Small Urban Watersheds." J . Water Poll. Control Fed., Vol 57, p 340. Rickert, D.A., (1984) "Use of Dissolved Oxygen Modeling Results in the Management of River Quality," J . Water Poll. Control Fed., Vol 56, p 94. Schubert, N.D., (1982) A Bio-Physical Survey of Thirty Lower Fraser Valley Streams," Canadian Manuscript Report of Fisheries and Aquatic Sciences 1644, Fisheries and Oceans, Canada. Seitz, W.D., Gardner, D.M., and van Es, J.C., (1982) "Recognizing Farmers' Attitudes and Implementing Non-Point Source Pollution Control Policies." Illinois Univ. at Urbana-Champaign. EPA-600/582-004. Shaw, L, and Yu, A.M., (1970) "Aerator Performance in Natural Streams," JASCE, Vol 96, p 1099. Shelton, S.P., Burdick, J.C.III., and Drewry, W.A., (1978) "Water Quality Modeling in a Low Flow Stream." J . Water Poll. Control Fed., Vol 50, p 2289. Singh, U.P., Wycoff, R.L, and Tate, G.L., (1979) "Approximate BOD Treatment Requirements for Urban Runoff," Jour. Env. Eng. Div., Proc. ASCE, Vol 105, p 3. Skaggs R.W., Gilliam, J.W., Sheets, T.J., and Barnes, J.S., (1981) "Effect of Agricultural Land Development on Drainage Waters in the North Carolina Tidewater Region." NTIS PB81-105959. Speece, R.E., (1979) "Supplemental Reaeration of Urban Canals." Aeration in Aquatic  Systems. IAWPR Prog. Water Tech. Ltd. Vol II, No 3. Permagon Press Ltd. p 151. Sprout, P.N., and Kelley, C.C., (1961) Soil Survey of Surrey Municipality. BC Dept of Agriculture, Kelowna. Technicon Instrument Corporation, (1973) "Industrial Method # 154-71w," Tarry town, NY. Thronson, Robert E., (1978) "Nonpoint Source Control Guidance, Agricultural Activities." EPA, Wash. D.C. Water Planning Div. NTIS PB-280 845. Town, C.A., (1986) "Instream Aeration of the Serpentine River," M.A.Sc. Thesis, Dept. of Civil Engineering, University of British Columbia. Vollenweider, R.A., (1974) A Manual on Methods for Measuring Primary Production in  Aquatic Environments. Blackwell Scientific Publications, Oxford. Whipple, W.Jr., Loughlan, F.P., and Yu, S., (1970) "Instream Aerators for Polluted Rivers," ASCE, Vol 96, p 1153. Wood, L.W., (1985) "Chloroform-Methanol Extraction of Chlorophyll-a", Can J . Fish. Aquat. Sci., Vol 42, p38. 121 Wright, R.M., and McDonnell, A.J., (1979) "In-Stream Deoxygenation Rate Prediction," Jour. Env. Eng. Div., Proc. ASCE, Vol 105, p 323. Young, R.A., Huntrods, T., and Anderson, W., (1980) "Effectiveness of Vegetated Buffer Strips in Controlling Pollution from Feedlot Runoff." J . Environ. Qual., Vol 9, No 3, p 483. ADDITIONAL BIBLIOGRAPHY Backman D.C, and Simonson, T.L, (1985) "The Serpentine River Salmonid Resource Studies 1984-85," Tynehead Zoological Park. Brett, J,R., (1952) "Temperature Tolerance in Young Pacific Salmon Genus Oncorhvnchus". J . Fish Res. Board Canada, Vol 9, No 6, p 265. Cooke, G.D., Welch, E.B., Peterson, S.A., and Newroth, P.R., (1986) Lake and  Reservoir Restoration. Butterworth Publishers, Stoneham, MA. Derkson, G., (1987) Biologist, Environmental Protection Service, pers comm. Duncan, W.F.A., (1986) "The Use of Community Metabolism Chambers in Ecotoxicological Testing and Monitoring of Aquatic Environments." Unpub Draft Proposal from Aquatrol Technologies Ltd, BC Min of Env, Waste Management Br. Feller, M.C., and Kimmins, J.P., (1979) "Chemical Characteristics of Small Streams Near Haney in Southwestern British Columbia," Water Resources Research, Vol 15, p 247. Henderson-Sellers, B., (1984) Engineering Limnology. Pitman Advanced Publishing Program, London, Great Britain. Hillebrand, H., (1983) "Development and Dynamics of Floating Clusters of Filamentous Algae'" Proceedings of the First 'International Workshop on Periphyton of Freshwater Ecosystems, Vaxjo, Sweeden, Dr. W. Junk Publishers, The Hague. Hirst, S.M., Truelson, R.B., Clark, B.C. and Easthope, C.A., (1979) "Impacts of Agricultural Land Drainage on the Fish and Wildlife Resources of the Serpentine -Nicomekl Watersheds, BC," Unpub Report, BC Min of Env, Fish and Wildlife Br. "Inventory and Analysis of Study Area Data on Stormwater Runoff," First Tennessee-Virginia Development District, 208 WQMP, Black, Crow & Eidsness Inc. Gainesville, Fla., May 1977. Markofsky, M., (1979) "On the Reoxygenation Efficiency of Diffused Air Aeration," Water Research, Vol 13, p 589. Moore, B., (1987) Biologist, BC Min of Env, Waste Management Branch, pers comm. 122 Patladino, A.J., (1961) "Investigations of Methods of Stream Improvement," Ind. Water and Wastes, Vol 6, No 3, p 87. Park, W.M., and Shabman, LA., (1981) "Considerations in Choosing the Appropriate Mix of Urban and Agricultural Nonpoint Pollution Control." Water Resource Bull., Vol 17, p 1023. Peterson, S.A., Sanville, W.D., Stay, F.S., and Powers, S.F., (1974) "Nutrient Inactivation as a Lake Restoration Procedure-Laboratory Investigations," US-EPA-660/3-74-032. Rinaldi, S., and Soncini-Sessa, R., (1978) "Optimal Allocation of Artificial In-Stream Aeration." Jour. Env. Eng. Div., Proc. ASCE, Vol 104, p 147. Smith, R., and Eilers, R.G., (1978) "Effect of Stormwater on Stream Dissolved Oxygen." Jour. Env. Eng. Div., Proc. ASCE, Vol 104, p 549. 123 APPENDIX I Water Quality Data 124 DATE SITE D.O. TEMP % SAT SC325 pH COD TOC TC NOx-N NH3-N ORG-N TOT-N P04-P TOT-P CHL-a mg/l (°C) uS/cm mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l ug/l JUL 14 176th 7.9 15.5 78.6% 7.49 41 10.7 28.6 0.613 0.359 1.06 2.03 0.097 0.513 JUL 21 176th 7.1 17.0 72.9% 216 7.82 34 14.3 31.8 - 0.394 0.450 1.03 1.87 0.082 0.186 JUL 28 176th 8.4 16.5 85.3% 251 7.58 26 5.8 24.0 0.376 0.336 0.32 1.04 0.185 0.246 AUG' 04 176th 7.1 16.8 72.1% 210 7.34 70 19.1 37.8 0.684 0.341 1.38 2.40 0.084 0.478 AUG 11 176th 8.5 14.2 81.8% 193 5.85 13 6.0 22.2 0.479 0.307 0.34 1.13 0.155 0.223 AUG 18 176th 8.7 13.0 81.6% 190 7.73 10 6.9 24.0 0.387 0.374 0.41 1.17 0.195 0.260 AUG 25 176th 8.9 13.9 85.2% 191 7.41 8 5.3 22.9 0.431 0.287 0.39 1.11 0.165 0.255 16 .4 SEP 01 176th 9.2 15.4 90.9% 193 6.94 30 7.0 23.6 0.338 0.337 0.44 1.12 0.225 0.324 12, .2 SEP 08 176th 10.1 13.8 96.9% 190 7.13 12 6.6 24.2 0.427 0.362 0.36 1.15 0.231 0.328 8, .5 SEP 15 176th 8.2 11.6 75.0% 155 6.71 31 10.5 23.5 0.672 0.189 0.55 1.41 0.182 0.307 16, .5 SEP 22 176th 9.3 12.4 86.1% 190 6.81 14 6.6 22.4 0.355 0.308 0.43 1.10 0.213 0.260 8. .0 SEP 29 176th 10.2 9.3 88.6% 184 6.49 11 6.8 22.1 0.424 0.280 0.35 1.05 0.220 0.294 11, .1 OCT 06 176th 10.2 8.6 86.8% 175 7.08 4 5.5 19.9 0.860 0.284 0.28 1.42 0.200 0.351 10. .3 OCT 13 176th 11.0 6.5 89.2% 187 7.18 19 11.6 25.5 1.260 0.288 0.31 1.86 0.250 0.245 11. .2 OCT 20 176th 10.8 5.1 84.2% 178 6.90 20 9.5 23.7 0.877 0.268 0.27 1.42 0.195 0.559 9. .0 OCT 27 176th 10.8 5.8 86.1% 196 7.75 16 7.2 22.9 1.080 0.316 0.3 1.70 0.226 0.281 10. .8 NOV 03 176th 9.5 7.8 79.6% 182 7.33 22 12.1 23.9 1.070 0.312 0.33 1.71 0.252 0.336 16. .5 NOV 10 176th 9.2 9.0 78.9% 164 7.31 42 17.9 28.4 0.913 0.233 0.55 1.69 0.137 15. ,9 NOV 17 176th 9.8 3.9 80.4% 273 5.97 50 23.5 31.8 3.430 0.236 0.61 4.28 0.212 0.363 NOV 24 176th 11.4 7.2 94.1% 191 6.51 31 14.8 19.6 3.670 0.086 0.53 4.29 0.0854 0.094 DEC 01 176th 10.0 5.6 79.3% 168 6.76 35 16.2 21.1 2.091 0.078 0.55 2.72 0.0639 0.104 Table A-1. Water Quality Conditions at the 176th Street Station (Site 176) (14 July to 01 Dec, 1987) DATE SITE D.O. TEMP X SAT SC325 pH COD TOC TC NOx-N NH3-N ORG-N TOT-N P04-P TOT-P CHL-a mg/l C°C) uS/cm mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l ug/l JUL 14 LatU/S 8.4 16.0 83.9% 7.54 28 6.6 19.9 1.612 0.040 0.45 2.10 0.050 0.135 JUL 21 LatU/S 8.8 16.1 88.6% 278 7.81 34 8.0 20.6 1.628 0.036 0.48 2.15 0.054 0.128 JUL 28 LatU/S 8.2 15.2 80.6% 313 7.64 30 7.0 20.8 1.304 0.029 0.3 1.63 0.048 0.106 AUG 04 LatU/S 8.2 15.3 81.3% 269 7.50 23 7.9 20.6 1.438 0.037 0.45 1.93 0.038 0.145 AUG 11 LatU/S 7.9 14.0 76.2% 261 7.51 22 6.0 20.0 1.673 0.047 0.25 1.97 0.039 0.101 AUG 18 LatU/S 8.7 12.1 80.0% 277 7.91 27 7.9 21.0 1.501 0.007 0.46 1.97 0.043 0.092 AUG 25 LatU/S 8.1 13.0 75.9% 431 7.53 29 5.8 17.7 1.616 0.005 0.58 2.20 0.045 0.133 16.3 SEP 01 LatU/S 8.1 14.4 78.8% 268 7.43 25 7.1 19.0 1.503 0.014 0.54 2.05 0.045 0.172 13.5 SEP 08 LatU/S 8.6 12.9 81.0% 289 6.82 18 7.1 18.3 1.419 0.005 0.39 1.81 0.040 0.151 7.5 SEP 15 LatU/S 8.1 11.3 73.1% 240 6.45 29 10.4 20.3 1.822 0.005 0.47 2.29 0.046 0.132 12.1 SEP 22 LatU/S 8.7 12.0 79.9% 275 6.71 21 7.1 19.1 1.346 0.023 1.2 2.57 0.044 0.117 8.2 SEP 29 LatU/S 9.7 8.8 82.8% 278 6.40 25 7.8 19.2 1.510 0.008 0.4 1.92 0.038 0.133 17.2 OCT 06 LatU/S 9.5 8.0 80.0% 273 6.77 17 7.6 19.1 1.780 0.063 0.32 2.16 0.070 0.117 10.9 OCT 13 LatU/S 10.7 5.8 85.3% 274 6.89 23 7.9 18.2 2.250 0.019 0.23 2.50 0.070 0.366 8.3 OCT 20 LatU/S 10.8 4.0 82.3% 271 6.78 20 8.4 18.5 1.820 0.022 0.23 2.07 0.060 0.183 8.1 OCT 27 LatU/S 10.5 5.4 •82.9% 300 7.54 22 12.9 22.0 1.560 0.020 0.62 2.20 0.106 0.154 9.4 NOV 03 LatU/S 8.6 7.7 71.9% 287 7.30 34 12.7 21.6 1.530 0.036 0.31 1.88 0.013 0.164 16.1 NOV 10 LatU/S 8.6 8.1 72.6% 279 7.33 30 13.7 23.6 1.750 0.010 0.33 2.09 0.038 9.9 NOV 17 LatU/S 9.8 3.9 74.3% 297 6.27 50 19.1 25.3 3.730 0.128 0.6 4.46 0.077 0.235 NOV 24 LatU/S 10.3 6.6 83.7% 200 6.60 41 16.8 21.7 4.240 0.089 0.61 4.94 0.0879 0.107 - DEC 01 LatU/S 9.5 5.2 74.6% 291 6.83 48 19.6 25.3 3.250 0.078 0.75 4.08 0.071 0.107 Table A-2. Water Quality Conditions at the Upper Latimer Creek Station, (Latimer U/S) (14 July to 01 Dec, 1987) DATE SITE D.O. TEMP % SAT SC325 pH COD TOC TC NOx-N NH3-N ORG-N TOT-N P04-P TOT-P CHL-a mg/l (°C) uS/cm mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l ug/l JUL 14 D t 1 0.5 22.5 5.7% 7.54 280 111.0 214.0 30.2 13.8 44.00 12.1 14.50 JUL 21 D t 1 0.6 23.0 6.9% 1476 7.90 349 122.0 223.0 26.6 12.1 38.70 11.0 13.80 JUL 28 D t 1 1.3 22.2 14.8% 1500 7.92 240 94.0 200.0 0.445 29.2 8.4 38.05 13.1 15.10 AUG 04 D t 1 2.6 21.0 28.9% 1586 8.01 307 126.0 212.5 0.049 18.7 9.7 28.45 7.45 10.40 AUG 11 D t 1 2.7 18.0 28.1% 1670 8.41 198 99.0 197.0 0.231 31.7 6.9 38.83 12.9 14.10 AUG 18 D t 1 1.0 16.1 10.1% 1583 7.83 304 85.5 170.0 0.054 33.6 11.2 44.85 11.4 13.40 AUG 25 D t 1 2.5 16.8 25.6% 1474 7.87 134 58.5 143.5 0.072 27.6 4.2 31.87 8.6 9.18 43.4 SEP 01 D t 1 3.1 22.2 34.9% 1431 8.95 175 58.0 134.5 0.151 26.9 4.5 31.55 9.15 9.92 24.0 SEP 08 D t 1 2.2 18.0 23.1% 1340 7.22 127 61.5 131.5 0.830 22.4 1.8 25.03 8.25 8.40 12.5 SEP 15 D t 1 1.5 12.9 13.8% 1285 7.27 144 61.0 132.5 0.620 21.0 1.2 22.82 7.4 7.88 50.3 SEP 22 D t 1 0.6 15.2 6.4% 1249 6.88 141 67.5 132.5 1.519 16.8 6.6 24.92 6.12 7.12 31.0 SEP 29 D t 1 1.7 12.0 15.4% 1261 6.82 170 74.5 137.0 3.647 13.5 1.3 18.45 5.4 6.10 52.0 OCT 06 D t 1 1.5 10.9 13.7% 1238 6.92 144 73.5 134.0 3.770 13.2 2.8 19.77 6.18 6.90 36.7 OCT 13 D t 1 3.7 5.5 28.9% 1228 7.03 153 141.0 206.0 2.960 14.4 1.6 18.96 6.04 6.68 56.5 OCT 20 D t 1 3.8 5.0 29.9% 1211 6.90 126 61.5 127.0 3.700 15.1 3.3 22.10 7.46 8.11 68.0 OCT 27 D t 1 3.3 5.8 26.3% 1201 7.47 170 67.5 123.5 1.640 15.3 1.7 18.64 6.88 7.49 59.3 NOV 03 D t 1 1.8 7.9 15.1% 1326 7.38 505 137.5 215.0 0.007 25.3 15.5 40.81 9.48 12.80 239.6 NOV 10 D t 1 1.6 8.0 13.5% 1302 7.45 315 105.5 179.0 0.375 23.3 9.3 32.98 8.97 124.4 NOV 17 D t 1 1.6 5.2 12.6% 1167 6.20 256 95.9 111.0 13.700 6.6 0.8 21.10 0.731 1.21 NOV 24 D t 1 5.1 6.1 41.0% 1011 6.31 218 83.8 95.0 7.030 2.05 5.23 14.31 0.478 0.676 DEC 01 D t 1 4.7 5.5 37.2% 1093 6.79 206 183.5 197.5 1.470 3.18 3.32 7.97 0.49 0.715 Table A-3. Water Quality Conditions at the Dairy Ditch 1 Station (14 July to 01 Dec, 1987) DATE SITE D.O. TEMP X SAT SC325 pH COO TOC TC NOx-N NH3-N ORG-N TOT-N P04-P TOT-P CHL-a mg/l (°C) uS/cm mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l ug/l JUL 14 LatD/S 8.4 16.0 83.9% 7.57 32 6.4 21.4 1.566 0.790 0.8 3.16 0.345 0.450 JUL 21 LatD/S 8.2 16.1 82.6% 310 7.97 42 8.4 21.8 1.615 1.030 0.65 3.30 0.240 0.316 JUL 28 LatD/S 8.1 15.2 79.6% 312 7.60 36 12.7 . 29.2 1.268 1.000 0.49 2.76 0.455 0.556 , AUG 04 LatD/S 8.2 15.3 81.3% 288 7.60 36 8.4 22.2 1.410 0.380 0.49 2.28 0.166 0.266 AUG 11 LatD/S 8.1 14.0 77.9% 291 7.94 25 8.4 24.0 1.638 0.650 0.52 2.81 0.259 0.354 AUG 18 LatD/S 8.5 12.1 78.2% 302 8.04 27 9.9 24.9 1.463 1.000 0.78 3.24 0.378 0.468 AUG 25 LatD/S 8.3 13.0 78.3% 433 7.54 31 6.1 18.2 1.618 0.211 0.36 2.19 0.104 0.168 11.3 SEP 01 LatD/S 7.9 14.4 77.0% 292 7.57 26 8.2 21.1 1.506 0.470 0.51 2.49 0.192 0.296 11.8 SEP 08 LatD/S 8.5 12.9 79.6X 312 6.71 18 8.0 21.2 1.406 0.474 0.35 2.23 0.194 0.281 7.4 SEP 15 LatD/S 8.0 11.3 72.4% 255 6.50 31 9.6 21.6 1.766 0.323 0.52 2.61 0.153 0.255 11.9 SEP 22 LatD/S 8.6 12.0 79.9X 288 6.56 21 8.6 20.6 1.346 0.131 0.49 1.97 0.077 0.168 9.0 SEP 29 LatD/S 9.3 8.8 79.6% 296 6.56 25 8.8 20.8 1.544 0.252 0.44 2.23 0.119 0.201 16.8 OCT 06 LatD/S 9.3 8.0 78.5% 298 6.70 17 8.6 20.7 1.810 0.251 0.44 2.50 0.170 0.252 12.3 OCT 13 LatD/S 10.5 5.6 82.9% 306 6.75 23 10.2 22.9 2.200 0.528 0.17 2.90 0.320 0.388 11.4 OCT 20 LatD/S 10.7 4.1 83.8% 283 6.63 20 8.5 19.4 1.870 0.178 0.2 2.25 0.138 0.190 9.0 OCT 27 LatD/S 9.8 5.3 76.8% 334 7.40 24 15.4 25.0 1.640 0.543 0.02 2.20 0.336 0.404 11.4 NOV 03 LatD/S 8.5 7.7 71.1% 318 7.30 45 14.7 26.0 1.490 0.698 0.86 3.05 0.320 0.521 27.9 NOV 10 LatD/S 8.5 8.1 71.8% 306 7.32 38 14.0 26.1 1.806 0.595 0.61 3.01 0.247 16.3 NOV 17 LatD/S 10.2 3.9 77.0% 309 6.30 50 20.2 26.7 3.900 0.168 0.66 4.73 0.088 0.147 NOV 24 LatD/S 10.7 6.6 86.6% 203 6.61 43 17.4 22.3 4.300 0.089 0.6 4.99 0.083 0.113 DEC 01 LatD/S 9.7 5.2 76.1X 279 6.83 53 18.7 23.8 3.280 0.080 0.74 4.10 0.071 0.139 Table A-4. Water Quality Conditions at the Lower Latimer Creek Station, (Latimer D/S) (14 July to 01 Dec, 1987) DATE SITE D.O. TEMP % SAT SC325 pH COO TOC TC NOx-N NH3-N ORG-N TOT-N P04-P TOT-P CHL-a mg/l (°C) uS/ero mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l ug/l JUL 28 D t 2 2.7 21.4 29.7% 882 7.65 195 86.5 156.0 0.050 26.5 2.9 29.45 3.13 6.26 AUG 04 D t 2 1.9 20.0 20.7% 860 7.78 152 76.0 137.0 0.029 20.5 3.3 23.83 2.75 4.65 AUG 11 D t 2 2.3 15.0 22.5% 704 8.24 195 53.0 114.0 0.080 24.1 15.5 39.68 2.88 8.25 AUG 18 D t 2 3.1 14.5 29.TA 682 7.80 137 67.5 133.0 0.037 25.6 3.2 28.84 2.94 5.33 AUG 25 D t 2 3.4 13.0 32.1% 979 7.74 186 63.5 129.0 0.041 33.3 4.7 38.04 2.68 6.55 213.7 SEP 01 D t 2 2.1 16.2 20.9% 857 7.56 144 63.0 119.0 0.049 26.3 6.1 32.45 3.48 6.54 146.8 SEP 08 D t 2 3.5 16.0 34.7% 726 6.95 104 54.5 102.0 0.050 22.5 1.5 24.05 4.24 5.70 115.5 SEP 15 D t 2 1.1 12.0 9.9% 790 7.09 138 60.5 110.0 0.269 29.8 0.2 30.27 4.23 6.32 99.9 SEP 22 D t 2 1.7 14.0 15.9% 925 7.00 145 59.0 124.0 0.064 37.7 7.9 45.66 5.12 ' 7.30 114.0 SEP 29 D t 2 2.3 9.7 19.9% 856 6.85 139 58.5 117.5 0.226 36.4 3.4 40.03 4.92 6.68 122.7 OCT 06 D t 2 1.1 8.5 9.5% 1272 6.92 191 69.0 163.0 0.580 57.6 3.2 61.38 9.30 11.20 89.8 OCT 13 D t 2 1.5 4.6 11.2% 1440 7.24 214 89.0 194.0 0.840 76.0 3 79.84 9.96 12.10 117.1 OCT 20 D t 2 1.6 5.5 12.9% 1335 6.97 211 88.5 183.0 0.590 67.6 12.2 80.39 7.78 9.34 130.7 OCT 27 D t 2 0.5 4.5 3.9% 1435 7.76 334 103.0 208.5 0.418 75.8 9.4 85.62 8.25 10.90 188.3 NOV 03 D t 2 0.1 8.1 0.8% 1199 7.52 274 98.0 147.5 0.027 40.0 7.2 47.23 5.38 9.12 201.8 NOV 10 D t 2 0.2 9.3 1.7% 1622 7.79 538 173.5 292.0 0.091 79.5 19.3 98.89 11.75 508.4 NOV 17 D t 2 2.8 7.3 23.2% 1757 4.59 126 49.1 54.5 13.530 2.01 2.19 17.73 0.0527 0.451 NOV 24 D t 2 5.7 9.0 49.2% 2130 4.39 129 121.8 127.0 8.880 1.39 1.78 12.05 0.0537 0.372 DEC 01 D t 2 4.1 6.1 32.9% 1960 6.18 164 112.1 127.0 5.550 12.20 4.3 22.05 0.0615 1.60 Table A-5. Water Quality Conditions at the Harvie Rd Ditch Station (28 July to 01 Dec, 1987) DATE SITE D.O. TEMP % SAT SC325 pH COD TOC TC NOx-N NH3-N ORG-N TOT-N P04-P TOT-P CHL-a mg/l ("C) uS/cm mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l ug/l JUL 14 80th 15.1 19.7 163.8% 8.78 22 6.3 21.0 0.699 0.073 0.49 1.26 0.152 0.237 JUL 21 80th 5.0 20.3 54.8% 257 7.94 29 9-5 26.2 0.800 0.285 0.51 1.59 0.111 0.258 JUL 28 80th 7.1 20.2 77.8% 227 7.59 34 10.4 26.6 0.973 0.276 0.58 1.83 0.110 0.226 AUG 04 80th 6.7 18.4 71.0% 255 8.08 25 8.7 27.5 0.939 0.215 0.58 1.73 0.096 0.250 AUG 11 80th 6.8 15.0 67.0% 229 8.32 25 8.6 24.9 0.819 0.145 0.34 1.30 0.081 0.235 AUG 18 80th 4.3 14.5 41.4% 209 8.07 35 9.9 28.0 0.784 0.296 0.62 1.70 0.115 0.266 AUG 25 80th 6.3 15.9 57.4% 225 7.96 24 7.2 24.5 0.685 0.152 0.56 1.40 0.082 0.236 20. .0 SEP 01 80th 5.1 17.2 52.6% 226 7.75 24 7.2 24.2 0.622 0.202 0.53 1.35 0.098 0.249 20. .4 SEP 08 80th 10.1 15.1 99.2% 227 7.22 18 13.8 29.8 0.598 0.042 0.38 1.02 0.101 0.199 10. .0 SEP 15 80th 4.0 12.1 37.0% 190 6.15 48 13.8 26.3 1.185 0.207 0.85 2.25 0.102 0.246 18. .2 SEP 22 80th 8.8 15.0 86.7% 219 6.91 27 9.5 24.0 0.630 0.203 0.67 1.50 0.141 0.306 37, .4 SEP 29 80th 3.1 9.9 27.3% 221 6.31 27 8.2 ' 24.2 0.129 0.266 0.59 0.99 0.368 0.548 39 .7 OCT 06 80th 3.7 10.5 33.0% 224 6.43 10 8.8 24.0 0.920 0.570 0.33 1.82 0.310 0.252 13. .5 OCT 13 80th 6.0 5.1 46.6% 225 6.60 25 9.7 24.3 1.410 0.498 0.34 2.25 0.270 0.468 13. .4 OCT 20 80th 8.5 6.5 68.9% 214 6.50 21 9.7 23.7 1.110 0.385 0.4 1.89 0.242 0.293 22. .7 OCT 27 80th 6.5 5.6 51.1% 235 7.27 111 11.3 24.9 1.410 0.212 0.28 1.90 0.247 0.363 22. ,0 NOV 03 80th 5.2 7.9 43.7% 244 7.12 36 15.9 27.1 1.260 0.553 0.47 2.28 0.022 0.377 27.3 NOV 10 80th 6.0 8.2 50.8% 219 7.24 30 14.7 24.9 1.182 0.253 0.61 2.04 0.199 16. .5 NOV 17 80th 6.9 5.2 53.8% 145 6.01 79 32.1 39.2 6.020 0.276 1.18 7.48 0.182 0.314 NOV 24 80th 8.8 8.0 73.7% 282 6.26 52 20.9 25.9 4.260 0.114 0.75 5.12 0.0927 0.139 DEC 01 80th 9.6 5.2 75.4% 240 6.86 40 17.2 22.3 2.170 0.152 0.67 2.99 0.0852 0.149 Table A-6. Water Quality Conditions at the 80th Avenue Station, (Site 80) (14 July to 01 Dec, 1987) DATE SITE D.O. TEHP X SAT SC325 PH COD TOC TC NOx-N NH3-N ORG-N TOT-N P04-P TOT-P CHL-a mg/l <°C) uS/cm mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l ug/l JUL 14 FrsHwy 8.0 21.5 89.8% 8.29 37 9.7 25.8 0.683 0.175 1.15 2.00 0.057 0.236 JUL 21 FrsHwy 11.8 22.0 133.6% 276 8.03 34 8.8 24.2 0.635 0.169 0.56 1.37 0.096 0.195 JUL 28 FrsHwy 9.8 21.5 110.0% 209 7.68 51 15.1 29.2 0.896 0.113 1.24 2.25 0.053 0.245 AUG 04 FrsHwy 9.6 20.8 106.3% 302 8.06 59 17.9 36.0 0.949 0.326 1.55 2.83 0.082 0.327 AUG 11 FrsHwy 10.9 18.2 114.7% 238 8.51 25 9.9 24.6 0.876 0.157 0.59 1.63 0.104 0.243 AUG 18 FrsHwy 7.4 18.0 77.4% 210 8.05 20 9.9 26.6 0.778 0.162 0.79 1.73 0.080 0.240 AUG 25 FrsHwy 11.2 20.0 122.1% 225 8.20 29 6.7 23.2 0.510 0.043 1.12 1.67 0.075 0.285 44.6 SEP 01 FrsHwy 8.8 20.5 96.4% 228 7.65 24 8.4 23.9 0.402 0.066 0.58 1.05 0.059 0.193 20.5 SEP 08 FrsHwy 13.3 19.0 142.5% 231 7.91 30 10.2 26.8 0.326 0.005 0.92 1.25 0.077 0.261 21.6 SEP 15 FrsHwy 7.4 12.4 68.6% 216 6.54 39 12.4 26.7 0.704 0.145 0.76 1.60 0.127 0.329 74.8 SEP 22 FrsHwy 8.3 19.3 88.7% 226 7.24 35 9.4 23.5 0.444 0.024 1.44 1.90 0.057 0.282 49.4 SEP 29 FrsHwy 13.6 17.0 139.1% 244 6.77 118 28.1 47.3 0.216 0.005 5.38 5.60 0.208 1.060 235.5 OCT 06 FrsHwy 9.3 15.5 92.3% 241 6.53 41 15.0 29.8 1.130 0.421 3.51 5.06 0.230 0.545 113.9 OCT 13 FrsHwy 7.3 8.0 61.1% 254 6.55 31 11.7 25.9 2.720 0.448 1.02 4.19 0.220 0.366 44.3 OCT 20 FrsHwy 5.1 8.1 42.7% 243 6.57 32 12.8 26.7 1.750 0.192 1.31 3.25 0.174 0.494 85.5 OCT 27 FrsHwy 7.4 7.7 61.9% 242 7.26 33 11.3 26.1 1.600 0.174 0.59 2.36 0.212 0.236 27.6 NOV 03 FrsHwy 3.8 8.8 32,. 6% 235 7.01 52 18.9 25.3 1.840 0.528 0.79 3.16 0.015 0.308 29.7 NOV 10 FrsHwy 6.5 8.3 55.1% 225 7.27 26 2.2 13.8 1.157 0.326 0.45 1.94 0.134 19.2 NOV 17 FrsHwy 7.0 5.4 55.2% 152 5.83 71 28.7 34.7 7.280 0.251 0.97 8.50 0.129 0.225 NOV 24 FrsHwy 9.3 8.0 78.3% 301 6.31 43 18.9 22.9 4.250 0.107 0.66 5.02 0.0781 0.152 DEC 01 FrsHwy 10.4 5.5 82.3% 202 6.99 30 13.7 19.0 1.590 0.049 0.52 2.16 0.0615 0.117 Table A-7. Water Quality Conditions at the Fraser Hwy Station, (Site FH) (14 July to 01 Dec, 1987) DATE SITE D.O. TEMP X SAT SC325 PH COD TOC TC NOx-N NH3-N ORG-N TOT-N P04-P TOT-P CHL-a mg/l <*C> uS/cm mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l ug/t JUL 14 #10Hwy 15.2 22.0 171.6% 8.55 32 11.3 26.3 0.378 0.016 1.27 1.67 0.022 0.163 JUL 21 #10Hwy 12.2 23.1 140.9% 232 8.46 25 5.7 21.2 0.335 0.007 0.84 1.19 0.009 0.114 JUL 28 #10Hwy 10.3 22.8 118.3% 203 7.88 32 11.4 25.8 0.657 0.056 0.68 1.40 0.018 0.109 AUG 04 #10Hwy 9.2 22.0 103.6% 189 8.16 35 14.7 25.8 0.766 0.071 0.83 1.67 0.012 0.130 AUG 11 #10Hwy 11.3 22.5 129.0% 223 8.72 31 9.2 27.6 0.864 0.023 0.99 1.87 0.023 0.154 AUG 18 #10Hwy 9.5 19.5 102.4% 184 8.05 33 8.6 22.4 0.748 0.141 0.9 1.79 0.014 0.113 AUG 25 #10Hwy 15.1 22.2 171.6% 204 8.70 37 8.5 24.3 0.760 0.049 1.7 2.51 0.021 0.232 142.4 SEP 01 #10Hwy 13.0 22.6 148.2% 215 7.94 28 7.7 22.7 0.286 0.049 0.96 1.30 0.011 0.113 SEP 08 #10Hwy 12.4 22.5 141.8% 223 7.67 38 • 11.7 26.8 0.528 0.023 1.34 1.89 0.010 0.233 65.1 SEP 15 #10Hwy 8.5 15.0 83.9% 199 6.75 23 7.3 20.3 0.597 0.045 0.01 0.65 0.019 0.152 49.9 SEP 22 #10Hwy 15.8 19.5 170.1% 323 7.84 51 11.5 25.8 0.517 0.243 1.18 1.94 0.015 0.114 113.4 SEP 29 #10Hwy 9.1 16.0 91.0% 211 6.62 27 9.7 23.7 0.789 0.225 0.77 1.79 0.047 0.160 54.1 OCT 06 #10Hwy 15.3 16.8 156.2% 248 8.00 23 10.8 25.8 1.070 0.306 0.77 2.15 0.070 0.589 66.3 OCT 13 #10Hwy 19.0 12.2 175.0% 211 6.86 84 27.4 42.8 1.260 0.016 4.13 5.41 0.040 0.541 311.0 . OCT 20 rtMOHwy 11.3 9.1 97.3% 288 7.29 75 10.9 22.8 1.160 0.005 0.58 1.74 0.060 0.179 67.7 OCT 27 #10Hwy 7.3 8.0 61.5% 237 7.18 37 12.0 •24.2 1.420 0.291 0.69 2.40 0.164 0.243 74.6 NOV 03 #10Hwy 4.9 9.0 42.3% 173 7.04 28 13.8 20.4 1.150 0.446 0.44 2.04 0.011 0.216 24.6 NOV 10 rfHOHwy 8.9 8.3 80.9% 191 7.34 22 11.6 22.7 1.135 1.14 0.075 17.5 NOV 17 #10Hwy 9.3 5.1 72.8% 189 6.23 35 13.7 18.6 2.610 0.141 0.51 3.26 0.099 0.225 NOV 24 #10Hwy 9.2 8.0 77.5% 347 6.28 43 14.4 18.5 4.090 0.275 0.56 4.92 0.0464 0.133 DEC 01 #10Hwy 10.5 4.6 81.2% 504 6.71 24 9.9 15.5 2.980 0.258 0.33 3.57 0.0189 0.039 Table A-8. Water Quality Conditions at the #10 Hwy Station, (Site #10) (14 July to 01 Dec, 1987) DATE SITE D.O. TEHP % SAT SC325 pH COD TOC TC NOx-N NH3-N ORG-N TOT-N P04-P TOT-P CHL-a mg/l (°C) uS/cm mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l ug/l JUL 14 152nd 11.4 22.6 129.9% 8.46 45 11.0 25.6 0.555 0.027 1.15 1.73 0.011 0. 128 JUL 21 152nd 11.1 23.3 128.5% 1623 8.97 72 9.6 24.2 0.010 0.96 0.003 0. 092 JUL 28 152nd 10.6 23.2 122.5% 2049 8.39 44 16.6 32.6 0.025 0.005 1.01 1.04 0.018 0. 119 AUG 04 152nd 6.2 21.8 70.2% 329 8.27 36 11.7 21.8 0.666 0.068 0.91 1.65 0.006 0. 110 AUG 11 152nd 8.4 23.7 97.9% 320 9.16 36 12.5 27.8 0.366 0.120 1.33 1.82 0.019 0. 183 AUG 18 152nd 13.0 19.5 140.4% 981 8.29 31 12.5 23.6 0.306 0.031 1.14 1.48 0.012 0. 082 AUG 25 152nd 10.8 21.5 121.2% 618 8.58 22 8.3 21.3 0.487 0.037 0.88 1.41 0.014 0. 105 61.3 SEP 01 152nd 15.3 23.2 176.9% 3932 8.70 86 12.0 26.6 0.025 0.007 1.45 1.48 0.004 0. 125 84.5 SEP 08 152nd 12.8 21.4 143.3% 515 8.24 28 12.2 27.6 0.148 0.005 1.15 1.30 0.007 0. ,164 56.9 SEP 15 152nd 9.2 16.1 92.1% 3027 7.33 27 10.0 25.0 0.338 0.108 0.85 1.30 0.006 0. .119 81.8 SEP 22 152nd 13.4 19.5 144.7% 1888 8.30 37 11.2 25.2 0.390 0.091 0.75 1.23 0.014 0. ,095 59.0 SEP 29 152nd 8.7 15.9 87.3% 1446 6.88 23 9.7 24.0 0.552 0.119 0.71 1.38 0.011 0. ,084 60.5 OCT 06 152nd 12.6 16.0 126.1% 1554 7.92 23 10.9 24.4 1.230 0.160 0.79 2.18 0.050 0. ,179 52.7 OCT 13 152nd 13.3 11.8 122.2% 608 7.73 25 10.9 24.0 0.800 0.040 0.62 1.46 0.050 0. ,139 49.1 OCT 20 152nd 13.5 10.5 120.4% 2647 8.09 86 11.8 24.3 0.627 0.005 0.81 1.44 0.030 0. ,208 70.8 OCT 27 152nd 12.3 8.5 104.9% 284 7.54 37 12.9 26.6 1.190 0.077 1.42 2.69 0.151 0. ,384 170.0 NOV 03 152nd 6.5 8.6 55.1% 1823 7.13 56 12.9 21.1 1.130 0.244 0.42 1.79 0.006 0. ,161 38.0 NOV 10 152nd 5.0 8.6 42.3% 846 7.17 30 13.5 23.2 1.220 1.22 0.099 25.8 NOV 17 152nd 8.1 5.7 64.0% 238 6.09 30 14.1 18.2 2.800 0.311 0.68 3.79 0.0962 0. ,177 NOV 24 152nd 9.1 7.6 75.9% 459 5.99 29 13.9 16.9 5.040 0.280 0.5 5.82 0.0293 0. .087 DEC 01 152nd 9.5 4.8 73.9% 1426 5.78 34 9.2 9.7 4.780 0.384 0.3 5.46 0.0166 0.062 Table A-9. Water Quality Conditions at the 152nd Street Station, (Site 152) (14 July to 01 Dec, 1987) 

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