Abstracts

al groundwater model has been developed for the Township aquifer system using MOD-
FLOW modelling code based on a rigorous data gathering and review exercise, and the
model is being used by the Township as a groundwater management tool. The model was
initially developed in 2003 and has been recently updated to incorporate changes to groundwater
extraction, and land development as well as additional hydrogeologic information that
have been gathered since the initial model development. The updated model is now being
used by the Township to determine the long-term availability of groundwater to support
future demand and aquatic needs by evaluating the effects of future municipal extraction
and land use development scenarios on water levels in aquifers, and base flows to aquatic
habitats. These results will be incorporated in landuse planning, and to identify groundwater
management options that will ensure the viability of groundwater as a sustainable long term
water-supply source for the Township in the decades to come.
235 - Evaluating the influence of regional stratigraphic
architecture on hydraulic conductivity variability in Early Silurian
carbonate rock aquifers, Guelph Region, southern Ontario
Elizabeth Priebe 1 , Christopher Neville 2 & Frank Brunton 1
1
Earth Resources and Geoscience Mapping Section, Ontario Geological Survey, Sudbury,
Ontario, Canada
2
S.S. Papadopulos & Associates, Inc., Waterloo, Ontario, Canada
The City of Guelph (City) relies on the underlying Early Silurian carbonate bedrock aquifers
for an average water taking of more than 40 million litres per day. Since 2005, the City
and the Ontario Geological Survey (OGS) have collaborated to improve the local understanding
of the bedrock sequence stratigraphy, biostratigraphy and rock/water geochemistry,
with the motivation that such characterization can provide valuable insight into the
distribution and quality of groundwater resources. The collaboration was initiated at a time
when the City was conducting a 50-year water supply master plan, and future projections
of population growth and water demands indicated that additional or alternative water
sources would be needed. The City has recently updated its water supply master plan, and
future projections once again indicate that additional water supply will be needed.
The main objective of this study is the integration of geological and physical hydrogeological
results from the various collaborative studies. This is being accomplished with the
creation of two separate datasets: the stratigraphic logs for the wells in which hydraulic
tests have been conducted and the associated discrete Kh estimates from those tests. For
the creation of the Kh dataset, the raw displacement data for more than 130 hydraulic tests
have been re-analyzed. Analyses have been conducted using a consistent interpretation
approach to enable a reliable comparison between parameter estimates. Three types of single-hole
hydraulic tests have been analyzed, i) single-hole pumping tests; ii) slug tests; and
iii) packer tests. The packer tests comprise either slug tests or short-term pumping tests
conducted within an interval isolated by straddle packers. The spatial density of hydraulic
testing locations is excellent, as is the vertical distribution of test intervals at the formation,
and at many locations, the member scale. The integration of this large set of high quality
IAH-CNC 2015 WATERLOO CONFERENCE
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