| Summary: | Reservoirs located in temperate climates undergo seasonal temperature fluctuations, warm in the
summer and cold in the winter. As a result, the temperature of the water seeping through
embankment varies with the season. Heat from the reservoir propagates through dams by two
main processes: convection and conduction. The variation in seepage water temperature can be
used as a tracer to detect and monitor seepage flow through dams. Temperature measurements
from the saturated zone of dams have been collected and qualitative and simplified quantitative
methods of data analysis have been used to detect relative changes in the seepage regime.
This thesis used two dimensional, uncoupled (fluid and heat flows) numerical models to simulate
heat flow through dams and determine seepage velocities. The numerical programs used in this
thesis were SEEP/W and a modification of CTRAN/W, produced by GEO SLOPE International
Inc. of Calgary. The programs were run in succession, beginning with SEEP/W. The analytical
method was first tested by comparing results to a closed form solution simulating one
dimensional flow (heat and water) through a homogenous material. Secondly the numerical
method was applied to analyse heat flow through a field scale model dam in Germany, followed
by an analysis of BC Hydro's Coquitlam Dam.
The numerical method was successful in simulating one dimensional flow. The method was also
capable of simulating fluid and heat flow through the field scale dam, which had a simple
stratigraphy. However, the hydraulic conditions at Coquitlam Dam are more complex and a two
dimensional model was not able to account for the flow variations at this dam. A three
dimensional model appears necessary to accurately simulate the fluid and heat flow conditions of
Coquitlam Dam. Temperature data collected from Coquitlam Dam was qualitatively assessed.
No obvious signs of preferential seepage paths were detected.
Although the numerical models used in this thesis were shown to effectively model fluid and heat
flow, the three step process required to use these modelling programs became cumbersome for
more complicated flow conditions. It is recommended that an integrated program be utilized to
analyse complex systems, such as Coquitlam Dam.
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