Saline water intrusion from the Fraser River estuary : a hydrogeological investigation using field chemical data and a density-dependent groundwater flow model
department or school: Science, Faculty of
department or school: Earth, Ocean and Atmospheric Sciences, Department of
data provider: DSpace
degree campus: UBCV
creator: Neilson-Welch, Laurie A.
issued: 2009-06-12T22:05:17Z
issued: 1999
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: Field data and a density-dependent groundwater flow model were used to understand the processes affecting saltwater intrusion and saline water distribution at a field site located adjacent to the Fraser River Estuary in Richmond, BC. At the field site saline water from the Fraser River intrudes a confined sand aquifer forming a saline wedge which extends laterally approximately 500 m into the aquifer. Chemical analysis of groundwater samples from three multi-level sampling wells (installed to obtain groundwater samples at closely spaced depth intervals), zone-specific piezometers, a West Bay well, and cone penetrometer tests was completed. The groundwater chemical data were used to delineate salinity contours defining the saline wedge. The chemical data were also analyzed using trilinear diagrams. Four chemically different groundwater facies were identified; shallow fresh groundwater above the saline wedge, brackish groundwater at the transition zone, saline water within the core of the saline wedge, and deep fresh groundwater beneath the saline wedge. Water level data from the zone-specific piezometers at the site were analyzed using a tidal filtering technique to determine average groundwater levels. The average water levels were then converted to equivalent freshwater head and compared for wells screened at the same elevation. The results indicated non-uniform flow conditions within the aquifer. Field data were not sufficient to thoroughly define the flow system. The numerical density-dependent groundwater flow and solute transport model Fracdens (Shikaze et al., 1996) was used simulate site conditions. The model was calibrated to field salinity data and a good match was obtained. The results indicated that the average groundwater flow regime at the site is typical for an area influenced by saltwater intrusion (circulation of dense saline water into the aquifer and then flow of saline, fresh, and mixed water toward the river under a regional freshwater gradient).…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/9050
extent: 9993432 bytes
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note: SALINE WATER INTRUSION FROM THE FRASER RIVER ESTUARY. A HYDROGEOLOGICAL INVESTIGATION USING FIELD CHEMICAL DATA AND A DENSITY-DEPENDENT GROUNDWATER FLOW MODEL by Laurie A. Neilson-Welch A thesis submitted in partial fulfilment of the requirements for the degree of Master of Science i n The Faculty of Graduate Studies Department of Earth and Ocean Sciences We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA 1999 © Laurie A. Neilson-Welch, 1999 In presenting this thesis in partial fulfilment of the requirements for an 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. Department of Earth dud Ocean £c fences The University of British Columbia Vancouver, Canada Date Jfaul /5~jm 11 ABSTRACT Field data and a density-dependent groundwater flow model were used to understand the processes affecting saltwater intrusion and saline water distribution at a field site located adjacent to the Fraser River Estuary in Richmond, BC. At the field site saline water from the Fraser River intrudes a confined sand aquifer forming a saline wedge which extends laterally approximately 500 m into the aquifer. Chemical analysis of groundwater samples from three multi-level sampling wells (installed to obtain groundwater samples at closely spaced depth intervals), zone-specific piezometers, a West Bay well, and cone penetrometer tests was completed. The groundwater chemical data were used to delineate salinity contours defining the saline wedge. The chemical data were also analyzed using trilinear diagrams. Four chemically different groundwater facies were identified; shal…
has type: Thesis/Dissertation
date issued: 1999-05
is shown at: 10.14288/1.0053150
language: eng
degree discipline: Oceanography
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/9050