News release

Essential Outdoor Cleaning Tips to Prevent Flooding, Pooling and Pollution

City services | April 19, 2022

Are you eager to scrub away the remaining traces of winter? As part of your spring cleaning routine, be mindful of what’s draining from your property and where it’s going. Improper drainage can potentially lead to flooding, pooling water and damage to your home.

In addition, debris, soap and chemicals can flow into catchbasins and eventually make their way into creeks and rivers. These pollutants all end up in Lake Ontario, which is our main source of drinking water.

Here are some tips on things to look for or fix to ensure your home is ready for spring.

Inspect and improve your property’s drainage

Have you noticed water pooling near your home or in your yard? Proper drainage is critical:

  • Make sure your downspouts drain away from your foundation and your neighbour’s property. The water should flow onto your garden or lawn to be absorbed.
  • Clear your eavestrough, downspouts and the catchbasins near your property of debris and leaves.
  • Consider adding a rain garden. Rain gardens are self-watering gardens that replace an area of your lawn to collect the water that flows off your roof, grass or driveway.
  • Inspect your basement sump pump if you have one, to make sure the water is being drained a safe distance from your home, where the water can soak into the ground.

Properly drain your hot tub, spa or pool

If you spent the chilly months keeping warm in your hot tub or spa and are now looking to change or drain the water, make sure you are doing so properly. Before emptying chlorinated, brominated or chemically treated water into the stormwater system:

  • Stop treating the water. Water must be held for at least seven days after the last chlorine or chemical treatment before emptying.
  • Avoid discharging the water in rainy weather to avoid flooding.
  • Salt water must drain into the sanitary sewer, not the stormwater system. You can connect to the sanitary sewer through a basement sink or floor drain.

Keep your spring cleaning clean

During your spring cleaning, but be mindful of what’s draining into the stormwater system:

  • Avoid washing or servicing your car (e.g. changing the oil) in your driveway. Soap and oil can run off your driveway and into the catchbasins.
  • Don’t spray fertilizer or pesticide onto the road, driveway or sidewalk where it can mix with stormwater and flow into the catchbasins.
  • Don’t dispose of waste, such as leftover paint or chemicals, by pouring them down the catchbasin. You can properly dispose of it at your local Peel Community Recycling Centre.

Prepare for upcoming renovations

Planning a home or yard renovation? Even if you’re hiring a contractor, be sure that the work you are paying for is done right:

  • Get a building permit first and don’t skip inspections. Sinks and toilets can accidentally be connected to a storm sewer, which allows wastewater to flow into the stormwater system.
  • Will your upcoming renovation involve excavation and digging? If rain water needs to be pumped out, make sure to have a conversation with your contractor to confirm that the water will be properly filtered before it’s emptied into the catchbasin or roadside ditch.

To learn more about the City’s stormwater system and the City’s new Storm Sewer Use By-law, visit


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