The Grand River Conservation Authority’s recent study of drinking water systems around the City of Guelph and the township of Guelph-Eramosa found the area is at “significant risk” of not having enough drinking water to meet future needs under drought conditions.
The GRCA began the Tier 3 Water Budget and Local Area Risk Assessment in order to evaluate the municipal drinking water systems located specifically within Guelph and Guelph-Eramosa.
The study followed a previous Tier 2 Risk Assessment that looked at the Grand River watershed as a whole.
The point of the study is to determine whether the water supply would meet future needs resulting from population growth.
It was found that two wells, Queensdale in the City of Guelph, and Arkell 1 in Puslinch, would not meet those needs.
Using a model to simulate groundwater and surface water flow to evaluate how water levels will change over time, both wells are predicted to run out of water by 2031 if nothing is done.
The study
According to Martin Keller, source protection program manager for the GRCA, it would be enough for the area to be deemed significantly at risk if a single well were found to have the potential to be non-operational in drought conditions.
That is despite the fact there are 21 wells in Guelph alone.
“It’s a conservative study but it’s obviously one that needs to be done,” said Keller.
He spoke to the Advertiser following a presentation to Erin town council on Aug. 14.
The GRCA presented its findings to the town because it has also been deemed at significant risk by the study. The Eramosa River is fed in part by groundwater springs, surface water and rain runoff from the southwest side of Erin.
The city of Guelph takes some of that water from the Eramosa River to supplement its municipal drinking water supplies, which in turn means groundwater in Erin is included in the significant risk categorization.
Due to similar connections between groundwater, surface water and wells, Puslinch and small portions of Milton and Waterloo are also affected by the significant risk designation, according to Keller.
The GRCA also ranked different uses or “takings” that deplete the municipal wells between mostly community uses, and industrial uses, as part of the study.
Industry users like the dairy company Gay Lea, and Nestlé Waters have a relatively minor influence on the water levels of the municipal wells. In comparison, the Dolime Quarry has a greater influence, Keller explained to council.
Prevention measures
Once a significant risk is determined, the GRCA is obligated under the Clean Water Act of 2006 to start laying out policies to protect at risk areas on behalf of the Lake Erie Source Protection committee.
Keller said there are a number of different measures that could be adopted to prevent Queensdale and Arkell 1 from running out of water.
One potential measure would be to focus on optimizing pumping rates of other wells to help balance out usage.
Another would be for the city and the township to think about adding other wells in other areas.
“We have an avenue forward. We have that list, now we need to figure out how to turn that into policies,” added Keller.
