Sewer systems run below the roads along the houses to catch water and waste and divert them to an appropriate location, such as a treatment facility. There are three types of sewer systems; Sanitary, Storm and a Combined sewer systems. Understanding Sewer Infrastructure is a good resource for more info.

Sewer systems, especially old or inadequate systems can cause water to back up into a home. 

The City of Toronto has a Basement Flooding Investigation Environmental Assessment Study to develop sewer improvement plans within the City’s right-of-way (roads).

The Basement Flooding Study Areas Site can help identify areas which the environmental assessment (EA) has been completed or when it will be completed. You can enter your postal code into a map. or use the chart to identify Active and Completed Study Areas…Where do you live?

Sewer System below road - separate storm and waste