Notice of study commencement: Southwest Guelph Water Supply Class Environmental Assessment

Guelph’s population is growing and the City is studying whether our local water resources can meet expected demand, particularly in southwest Guelph. We’re looking into whether we can increase capacity at our existing wells and what new infrastructure would be needed to increase water supplies to accommodate expected growth.

The City is starting a Municipal Class Environmental Assessment to determine longer term water supply capacity in southwest Guelph. The study will assess the environmental impacts of using more groundwater resources and the need for and support the design of a groundwater protection system to address drinking water quality concerns related to past operations at the Dolime Quarry.


In response to recommendations from the 2007 Water Supply Master Plan, the City started the Southwest Quadrant Class Environmental Assessment in 2007 to expand existing water supplies in southwest Guelph. The project was put on hold in 2010 due to the City’s concerns around water quality and quantity impacts as a result of legal and permitted operations at the Dolime Quarry. In 2020, Council approved a mediated solution to address the City’s concerns about how operations at the Dolime Quarry could affect Guelph’s drinking water.

The Southwest Guelph Water Supply Class Environmental Assessment will build on the work started in 2007 to determine whether we can increase water supply capacity at existing wells in southwest Guelph and what, if any, new infrastructure is needed. The relaunched assessment will also include the study of surface and groundwater interactions at the Dolime Quarry so we can determine how much additional water supply is available to meet Guelph’s growing needs, and what the environmental impacts of using these groundwater resources is. Finally, the study will inform the need for, design and function of a water management system at the quarry to protect Guelph’s drinking water for the long-term.

Study area

map of study area

The process

This project will follow the Schedule B Municipal Class Environmental Assessment (2015, as amended), which is an approved Class of Environmental Assessment under the Environmental Assessment Act. The study will take up to five years to complete.

Feedback is an important part of the Class Environmental Assessment. Along the way the City will inform and seek input from partner Indigenous governments including the Mississaugas of the Credit First Nation, Six Nations of the Grand River and the Haudenosaunee Confederacy, and from urban Indigenous peoples with ties to Guelph (e.g., First Nation, Métis, Inuit and mixed ancestry Peoples). The City will also host engagement opportunities for residents and other interested persons or groups throughout the process.

Technical studies are the first step of this project with opportunities for wider public engagement beginning in 2024. We’ll announce all opportunities to share feedback on our website, through local media and on our Twitter and Facebook channels. Engagement opportunities will also be posted at

Once complete, we’ll post a report of the Class Environmental Assessment on our website and share for public review.

For more information

Visit the City’s environmental assessments and studies webpage for the latest information about the Southwest Guelph Water Supply Environmental Assessment.

To provide your comments, request additional information or be added to the project mailing list, contact a project team member.

Dave Belanger, M.Sc., P.Geo.
Water Supply Program Manager, Water Services
City of Guelph
519-822-1260 extension 2186
[email protected]

Matthew Alexander, M.Sc., P.Geo.
Project Manager, AECOM Canada Ltd
[email protected]