An unseasonably warm spring has many homeowners turning early to gardens and outdoor improvement projects. Using simple new approaches and attractive native plants they can help protect Lake Ontario as they dig into spring gardening projects.

In urban environments rainwater runs off homes and businesses picking up pollutants, carrying them into local waterways. Because so much water runs off hardened surfaces like roads, roofs and driveways, rather than being absorbed into the ground, the volume of stormwater can cause erosion, flooding and water quality issues.

“Many people do not realize that the stormwater grates on their street often drain directly into creeks and streams with little or no treatment,” said Robb Lukes, Water Resource Specialist with Credit Valley Conservation (CVC). “It eventually finds its way to Lake Ontario, the drinking water supply for more than eight million people.”

Fortunately new technologies and approaches can help reduce and filter runoff before it hits storm drains.

Permeable paving allows water to pass through hard surfaces so it can be absorbed into the ground. Permeable interlocking stone as well as new permeable concrete and asphalt are available.

“If we can reduce the amount of runoff heading into local waterways, that will make a big difference,” said Muneef Ahmad, Water Resources Engineer with the City of Mississauga. He notes that high volumes of rainwater, even from regular rainfall, can warm streams and degrade aquatic habitat.

Disconnecting downspouts that connect directly to the stormwater system is one simple thing that can help, as long as it is done correctly. Instead of allowing runoff to flood the stormwater system, a rain barrel can be used to capture the rainwater, or water can drain to the lawn and/or a rain garden. Rain gardens are shallow depression gardens designed with special soils and plants to receive roof runoff and allow it to soak into the ground. These gardens are sized to drain within one to two days after a rainstorm.

“Exploring better ways to deal with stormwater runoff is critical to protecting and improving the lake and the environment around our shoreline,” said Christine Zimmer, Manager of Protection and Restoration for CVC.

Urban challenges such as runoff are taking a toll on Lake Ontario. CVC is taking action by developing a Lake Ontario Integrated Shoreline Strategy (LOISS) to study water quality, quantity and wildlife habitat along the shoreline and identifying opportunities to protect and restore it. More information is available at

For specific information on downspout disconnection, please email [email protected] or call the City of Mississauga Transportation & Works at 905-615-3200, ext. 4793.


Conservation Authorities are a provincial/municipal partnership. CVC was established by an act of the province in 1954 with a mandate to protect all natural resources other than minerals in the area drained by the Credit River. We have been working for over 50 years with our partner municipalities and stakeholders to protect and enhance the natural environment of the Credit River Watershed for present and future generations.

Media Contact
Jon MacMull
Communications Specialist
Credit Valley Conservation
905-670-1615 ext. 385
[email protected]

Information Contact
Christine Zimmer
Manager, Protection and Restoration
Credit Valley Conservation
905-670-1615 ext. 229
[email protected]

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