The City of Toronto Sewers By-law (Municipal Code, Chapter 681) aims to protect public safety, the environment and City infrastructure by setting strict limits on what can be discharged into the sewers system and natural watercourses.

  • Some substances are completely prohibited, where others are restricted to defined safe limits.
  • Nothing other than rain and melted snow should ever enter a catch basin (square grates on the road).
    • Catch basins are connected to storm sewers, which drain directly into rivers, streams and the Lake.
    • Anything other than stormwater can harm the environment, cause sewer damage and lead to flooding.

Toronto Water is working to educate residents and businesses about their role in upholding the By-law, and ensuring compliance through regular monitoring, sampling, testing and inspection.