Inflow & Infiltration

The Town’s sewer system is comprised of two parts: storm sewers and sanitary sewers. Storm sewers collect stormwater such as excess water from rainfall, snowmelt or run off, and properly manages it before discharging it to lakes and streams. Sanitary sewers carry wastewater to treatment plants for processing before returning it to the environment.

Inflow and infiltration is the term used when water that should be entering the storm sewer system makes its way into a sanitary sewer. This can be a result of incorrectly connected sump pumps and downspouts, and/or damaged storm and sanitary sewer pipes.

Why is inflow and infiltration a problem?

Inflow and infiltration is a problem for a number of reasons:

  • It overloads the sanitary sewer system, leaving less capacity for existing residents and future growth
  • It increases the cost of water to residents because sewage treatment plants are required to treat a higher volume of flow
  • It may cause sewage backups in basements
  • It puts excess stress on wastewater treatment plants and infrastructure

What can you do to prevent inflow and infiltration

There are a few simple things you can do to ensure your property doesn’t contribute to inflow and infiltration.

  • Ensure your home’s downspout is disconnected from the sanitary sewer system and flowing properly towards the storm sewer
  • Ensure sewer grates on your street are free from debris such as leaves and garbage to ensure storm water drains properly
  • Use a rain barrel
  • Participate in Inflow and Infiltration reduction projects happening in your neighbourhood

What is the Town doing about Inflow and Infiltration?

Finding and reducing inflow and infiltration is a high priority. It reduces the cost of treating stormwater water as sewage, helps to maintain and extend the life of costly infrastructure and helps to ensure there is enough capacity for wastewater to move through the system. 

Current Inspection and Repair Work Projects

The Town will periodically use sewer cameras to view sewer lines in areas that have higher flows than normal. The Town can also use smoke and dye testing to identify some of these problem systems that affect the Municipal sewer system.

What to Expect When Work Is Happening In Your Area

Once a source of inflow and infiltration has been found, the Town will complete a thorough condition assessment to determine the best method of addressing the issue. These could include:

  • Public education
  • Active enforcement (fines)
  • Open-cut construction
  • Trenchless sanitary repairs

Frequently Asked Questions