​​​​​​​​​​​​​​​​​​​​Stormwater Drainage System

The City’s stormwater drainage system is designed to collect, move and treat stormwater runoff before it is released into the environment in order to protect Brampton from flooding, erosion, environmental damage and negative impacts on water quality in local rivers and streams. It consists of catchbasins, storm sewers, manholes, oil grit separators and filters, stormwater ponds, flood conveyance channels, and natural rivers and streams.​​

Storm Sewer System

The storm sewer system is the backbone of the City’s stormwater system. It includes:

  • ​40,000 catchbasins
  • 28,000 manholes
  • 1980 km of storm sewers
  • 189 stormwater ponds
  • 127 water quality units​


Catchbasins are the main inlet ​​points into the storm sewer system. They are located underground and are typically placed at the curbside of streets and in ditches or parks. They allow stormwater runoff from road and parking lot surfaces to flow through a grated cover and into the underground catchbasin. Runoff falls down into the body of the catchbasin and then flows into a storm sewer through a connected outlet pipe located in the lower part of the catchbasin.

Storm Sewer

Storm sewers are pipes that receive the stormwater runoff from catchbasins and transport it towards a destination point which is typically a stormwater pond, river or creek. They are located under the street surface, under parking lots, and under parkland.


​Sections of storm sewer are connected by manholes, which allow for maintenance and inspection of the sewers

Oil Grit Separators and Filters

Stormwater oil grit separators and filters are underground devices that are connected to the storm sewers. They capture pollutants like oil and sediments from stormwater runoff. Oils and other pollutants collect on paved parking lots, driveways and roads and get carried by runoff to an oil grit separator. Oil grit separators remove oil and sediments from runoff and store them until the devices are cleaned out. In the oil grit separator sediments settle and are stored at the bottom, while oily fluids rise to the top for storage. This allows cleaner stormwater runoff to drain into the City's stormwater drainage system. By capturing these pollutants, it prevents them from flowing into local rivers and creeks through Brampton’s stormwater drainage system.

Stormwater Ponds

Stormwater runoff collected by the storm sewer system is taken either directly to a river or stream, or to a stormwater pond. A stormwater pond is constructed to receive the runoff and temporarily store it. The water in the pond is then released slowly over a period of time so that it does not cause flooding or erosion. Stormwater ponds also allow contaminants in the water to fall to the bottom of the pond, resulting in cleaner water being discharged into the environment. Areas, where runoff is not managed by a stormwater pond, are at risk of flooding, erosion, and environmental harm.

Channels, Rivers and Streams

Flood conveyance channels and natural rivers and streams are the final destinations for stormwater runoff. More frequent and increasing amounts of runoff can cause erosion within rivers and streams, resulting in environmental and property damage. Extreme storm events can also cause erosion, as well as blockages and damage from fallen trees and other debris that is carried along in floodwaters. It is necessary to undertake periodic maintenance, restoration and rehabilitation activities in rivers and streams to deal with erosion and preserve their capacity to carry flood flows.

Contact Environment and Development Engineering

Planning, Building and Growth Management
2 Wellington St W, Brampton​