Managing Stormwater At Home

Ottawa has over 2,700 km of storm sewers and 1,600 stormwater outlets which allow rainwater and other runoff to flow directly to our rivers, creeks and canal. This water is not treated and has harmful effects on delicate marine ecosystems.

EnviroCentre works to educate residents on what they can do to reduce runoff from their properties.

Top 10 tips to protect our river … from home!

  • Direct your downspouts to a lawn or garden
  • Scoop your pup’s poop
  • Grow native plants
  • Say no to driveway sealant!
  • Keep your property chemical free
  • Reduce salt use in the winter
  • Pile snow where it can drain into the ground when it melts
  • Keep your car maintained so it doesn’t leak oil or fluids
  • Learn about the benefits of rain gardens … and then install one!
  • Keeps the suds off the streets, use a car wash!

Glossary of Common Terms


Bioswales are permeable surfaces usually with plants and/or river stone that run along roads or parking areas to collect rainwater runoff. They generally have inlets to guide water into them and sloped sides to create a basin effect.


A depave is a community event where asphalt is removed by hand. The asphalt is scored into sections that can be removed and replaced with green space such as grass, trees or gardens.

Eavestroughs & Downspouts

An eavestrough is a small gutter that runs along the edge of a roof. The downspout brings the water from the eavestrough to the ground. Downspouts should be long enough that the water expels a minimum of two metres from any foundation.

Native Plant

A plant that naturally grows in the ecosystem in which it is planted. It requires little maintenance and will thrive in local conditions.

Naturalized Garden

A naturalized garden incorporates local native plants and the surrounding environment into its design. It is often informal and has a feel of wildness.


When you visit the river you may see a large opening, often with a metal grate. This is where water that flows off our city streets and into storm sewers is released into our river. Know the flow!

Permeable Driveway

A permeable driveway allows water to flow freely through it into the water table. It can be made of specifically engineered and installed pavers or hardscaping, it could be gravel and it could be blocks that allow for vegetation to grow amongst it.

Rain Barrel

A rain barrel is a container that captures runoff from downspouts or directly from the sky.

They should have a screen to prevent larvae and be raised off the ground securely for best use of the water.

Rain Garden

A rain garden is a special garden with a deep sub-base that allows a great deal of water to be absorbed on-site.


Runoff is the water that flows from roofs, driveways, roads, and any other hardscaping. In Ottawa, most runoff flows directly and untreated into watersheds.

Storm Sewer

The fish you see on this storm sewer indicates that water going down it will flow directly to our rivers untreated. Think of the fish!


Transpiration is the process by which trees and other plants absorb water through their roots and release it through their leaves. A large tree can absorb up to 375 litres per day!

Top 10 Things to Know About Rain Gardens!

Curious to know more about rain gardens? Watch this video to learn the top ten most important things you need to know!

Case Study: Building a Community Rain Garden

In 2021 EnviroCentre installed a demonstration rain garden on behalf of the City of Ottawa at the Manordale-Woodvale Community Centre.

Learn about the process and how rain gardens help to keep Ottawa rivers healthy.

Useful resources

Rain Ready Ottawa – The City of Ottawa’s Rain Ready page provides lots of interesting information and resources!

Ottawa Field Naturalist Club – Visit this site to learn about the nature outside our doorstep!

Ottawa River Keeper – No one knows our rivers better than the Ottawa River Keeper.

Landscape Ontario – Learn how fusion landscapes are designed to thrive naturally with rainwater.

Ottawa Wildflower – An Ottawa-based organization that provides education and seeds to anyone looking to learn about gardening with native plants.

Local nature-based climate solutions map – This interactive map showcases case studies of nature-based climate solutions across Canada.

Rideau Valley Conservation Authority & Mississippi Valley Conservation Authority to stay connected to our watersheds!

Rain Garden Mural

This painting by local Ottawa artist Emily-Rose depicts the important role rain gardens play in protecting our rivers!

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