Basement Flooding

The City of St. Catharines provides guidance to help residents prevent and respond to basement flooding. Staying prepared through regular maintenance can save both time and money, whether through simple, cost‑effective steps or more comprehensive flood‑prevention upgrades.

What to Do If Your Basement is Flooded

Report it by calling Citizen's First at 905.688.5600 and contact your insurance provider as soon as possible.

Determining the cause of basement flooding is not always easy. The City needs as much information as possible from affected residents, including:

  • Where is the water coming from?
  • When did it start?
  • How much water is there?
  • Make sure to note both the colour and odour of the water.

Flood Prevention

Our Basement Flooding Prevention Guide for Homeowners provides vital information on:

  • Our St. Catharines sewer system
  • Types and causes of basement flooding
  • Immediate and long-term flood prevention techniques
  • Insurance considerations
  • What to do if your basement is flooded and clean-up

Flood Action Checklist

Our Seasonal Property Flood Action Checklist provides handy tips on flooding prevention measures you can take regularly and before a rainstorm.

Flood Alleviation Program (FLAP)

The City’s Flood Alleviation Program (FLAP) helps eligible homeowners protect their properties from basement flooding by offering rebates that cover up to 90% of eligible costs, to a maximum of $5,000.

The program applies to both single‑detached and semi‑detached residential homes built before 2012 and supports the installation of flood‑prevention devices such as backwater valves, as well as the disconnection of weeping tiles from the sanitary sewer and their reconnection to a sump pump system.

This work aims to reduce the risk of sanitary sewer backups during heavy rainfall events and to improve long‑term flood resiliency in our communities.
Learn more about the program by visiting www.stcatharines.ca/FLAP
For questions or assistance, contact the Program Coordinator at FLAP@stcatharines.ca.

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