Urban Drainage Management

In highly urbanized areas, moderate to heavy rain storms can create significant amounts of stormwater runoff (excess water that is not absorbed into the ground). In two large areas – known as the Still Creek-Brunette River Drainage Area and the Port Moody-Coquitlam Drainage Area – Metro Vancouver provides some services to municipalities to safely channel runoff from storms and help prevent flooding.

What is a drainage area?

A drainage area is an urban version of a natural watershed. A watershed is an area of land surrounding a body of water, such as a river, stream or ocean. A watershed acts like a funnel by collecting all the water from rain or melting snow that falls within its boundaries and channelling it into the body of water.

In the past, many urban watersheds were seen primarily as drainage networks and the goal was to move problem water into pipes and ditches and out of the area as quickly as possible. Current approaches try to look at the watershed as a whole and manage water closer to where it falls, using approaches like rain gardens and green roofs that slow the flow of water.

Metro Vancouver’s role

In consultation with municipalities, Metro Vancouver provides planning and maintenance services for specific facilities in the Still Creek - Brunette River Drainage Area (the Brunette Basin) and the Port Moody - Coquitlam Drainage Area. Metro Vancouver is responsible for channeling stream flows in these areas by making sure that designated culverts, creeks and grills are kept clear and functioning properly.

Still Creek – Brunette River Drainage Area

The Still Creek-Brunette River Drainage Area is a large, highly urbanized watershed. The 73 km2 drainage area has over 200,000 residents and covers parts of Burnaby, Vancouver, Coquitlam, New Westminster and Port Moody (see map).

In recent years, Metro Vancouver has replaced the Cariboo Dam fish ladder, allowing fish to return to local creeks for the first time in decades. It has also worked with community groups to coordinate stream clean-ups and tree planting, cleared blockages and improved fish habitat.

Metro Vancouver facilitates the Brunette Basin Coordinating Committee, which coordinates stewardship and maintenance activities in the watershed and implements actions outlined in the Brunette Basin Watershed Plan. The committee includes municipalities, streamkeeper groups, the Department of Fisheries and Oceans (DFO) and the British Columbia Institute of Technology (BCIT).

 

 

 

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Port Moody – Coquitlam Drainage Area

The Port Moody-Coquitlam Drainage Area is just over 7 km2, has 13 creeks and covers parts of Port Moody and Coquitlam (see map). Recent Metro Vancouver maintenance activities in this drainage area include installing flow monitors, installing large pipes, clearing blockages and maintaining fish ladders to ensure fish passage. A long-range integrated stormwater management plan for the drainage area is currently being developed.