Contact 311 to submit a service request for illegal dumping into the sewers, watercourses, streams or rivers (paint, pool water, debris of any type, soap, cleanser, hazardous material etc.)

The industry/business responsible for the spill must submit a detailed spill report, as per Section 9 of the Sewers By-law, within five days after the spill.

Notices: Fog and Dye testing

If you have witnessed someone on a scooter spraying what looks like paint on/in a City sewer, please see: West Nile Virus - Vector Borne Diseases - larvicide program

Hazardous waste disposal - what pollutants are allowed to enter the sewer system

Toronto does not allow the discharge of hazardous waste into its sewer system. You can obtain a listing of what pollutants are allowed to enter the sewer by referring to the Sewers By-law (Municipal Code Chapter 681 - Sewers) at

You can also contact the Ontario Ministry of the Environment, Conservation and Parks to learn more about their hazardous waste regulations.

The following must also not be discharged into the sewer:

  • grease/oil
  • sanitary pads
  • condoms
  • floss
  • petroleum products
  • pharmaceuticals
  • paints
  • solvents

Sewers by-law enforcement

Pollutants that are permitted to be discharged into the sewer, can only be discharged in concentrations that are compliant with the sanitary/combined sewer by-law limits and the more stringent storm sewer by-law limits. Any person discharging above the by-law limits are considered to be in non-compliance and a notice of violation may be issued. Environmental Bylaw Officers frequent industry/business facilities for inspection and sampling via a maintenance access hole.

Car washing

The Sewers Bylaw does not specifically prohibit car washing on private driveways, but it does restrict the dumping of soaps, detergents, oil and dirt into the sewer system. The waste water with these chemicals flow into the sewer and then untreated to the natural environment.

Note: Either don't use detergents to wash your car or wash on your lawn on porous surface. If washing cars on driveways, use a pail and wash cloth sponge and rinse the dirty water into the pail. The pail should be emptied onto the lawn, into the garden or down a (sanitary plumbing) drain in the house.

This ensures that the dirty rinse water goes into the sanitary sewer and gets treated at our sewage treatment plants. Drive through and coin car washes discharge their wastewater to the sanitary sewer for treatment and are good alternative to washing on your driveway.

Outdoor water use to clean hard surfaces

Outside garbage areas should not be cleaned using running water that has the potential to flow to a catchbasin in the surrounding area. Mobile wash operations (i.e. power washing) must also prevent wash water from entering catch basins.

According to the Municipal Code Chapter 681 Sewers (681-4) Storm Sewer Requirements, the only water that is allowed to enter a storm catchbasin (that is the grate that is found usually behind the restaurant in the driveway or alley way) is clean rain water. The bylaw limits for the storm sewer are much stricter than that of the sanitary sewer limits, as the water flows to the lakes and rivers untreated, thereby ensuring water quality.

Washing down a garbage area with water, violates the storm sewer parameter limits as there would be suspended solids and most likely the wash water would be contaminated by food products which in turn would violate the Biochemical Oxygen Demand (BOD) parameter.

The area outside needs to be kept clean by disposing of the garbage in a manner that does not require the need to wash the area with water. If the garbage area requires cleaning then it may be swept and clean of debris which would be placed into the solid garbage bin. If water is necessary, then the water should be bermed in an area and then a liquid waste hauler may be hired to vacuum the water and take it away for proper disposal. All restaurant activity should remain inside the building and only rain water is allowed to enter the storm sewers. Anything other than rainwater or snowmelt may be considered a spill.

Mobile wash operations' wash water also violates storm sewer by-law limits as soaps and other cleaning products used are not permitted in the storm sewer. Simply power washing with water alone also dislodges/dissolves contaminants from the surface being cleaned.

Connection of weeping tiles to the City sewer system

The Municipal Code Chapter 681 - "Sewers By-Law" does not permit the connection of weeping tiles to the City's sewer system. Weeping tile flow should be pumped to grade and safely discharged on the property.


No person shall install or operate within the City any garbage grinding devices for domestic purposes, the effluent from which will discharge directly or indirectly into a storm or combined sewer according to the Sewer Use Bylaw (Municipal Code, Chapter 681-10,Section E)