Halton Region 1151 Bronte Road Oakville, Ontario, Canada L6M 3L1
Phone: Dial 311 or
905-825-6000
Toll free: 1-866-442-5866
Email Halton Region
Still have questions? Visit the Frequently Asked Questions (FAQs) page for more information.
Having a basic understanding of the plumbing and drainage system both inside and outside your home can help you to determine what steps you need to take to prevent basement flooding.
Your home has a separate storm water and wastewater (sanitary sewer) collection system. Halton Region is responsible for the wastewater collection system while your Local Municipality is responsible for storm water management. Any pipes or components of the plumbing system that are on the private property is the homeowner's responsibility and is referred to as private infrastructure.
The storm water system is designed to collect rain and snow melt (clear water) from streets and properties and direct this flow to a nearby pond, creek or lake. The sanitary sewer system is designed to collect water from toilets, sinks, showers and laundry facilities and direct it to wastewater treatment facilities where it receives a high level of treatment prior to being discharged back to the environment.
Until Building Code changes and subsequent by-laws were enacted in the mid to late 1970's, it was common practice to connect foundation drains and roof leaders directly to the sanitary sewer system. Although these connections are now no longer permitted as part of current construction practices, many areas in Halton Region constructed prior to 1978 continue to have direct storm water connections to the sanitary system which are now considered to be improper and are a major source of excessive inflow and infiltration (I & I). For more information on I&I please visit the web page.
Rain falls on the roof of your house and drains down the storm drain. The rain collects on the ground around the perimeter of your house. It seeps through the earth to the bottom of the foundation, where it finds its way into the sanitary lateral then into the municipal sanitary sewer. Rain fall should be redirected and drain into the storm sewer.
Rain falls on the roof of your house and drains down the storm drain. At ground level it is redirected down a downspout extension & splash pad, and finds its way into the storm sewer. In heavy rain water can get backed up the storm drain. On these occassions the rain water is redirected down a second drain located further up the storm drain. A sump pump directs this water outside and a backwater valve ensures this water does not drain into the sanitary sewer.
Homes that have improper storm water connections in place can be more susceptible to basement flooding. This is because of the high volumes of storm water being directed to the sewer main in the street, from sources such as downspouts and weeping tiles. To help prevent basement flooding homeowners need to understand the source of the problem and redirect the storm drainage from their property properly.
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There are several possible causes of basement flooding from sanitary sewer water, storm water , or a combination of both.
If your basement is flooded or wet from only storm water possible causes may be:
If your basement is flooded from a sewer backup, (or combined with storm water), possible causes may be:
Most often basement flooding occurs after a heavy rainfall or snowmelt. Basement flooding from a sanitary sewer backup can occur when too much storm water enters the sanitary sewer system during wet weather events.
When this occurs, residences at lower elevations, especially those without adequate backflow protection, may experience a sewer backup into the basement from the floor drain or other plumbing fixtures. I & I is a significant contributor to basement flooding and is something that individual homeowners can effectively address by assessing your property drainage and making changes to remove improper storm water connections from the sanitary sewer system.
Storm Water
Sewage / Storm Water
Residents can also help by conserving water. In households without low-flow fixtures, up to 75% of water is used to flush toilets and take showers.
If your basement floods and you suspect it is sanitary water call Halton Region at 905-825-6000 or toll-free at 1-866-442-5866 . Regional staff will inspect the problem, assess the flooding, attempt to determine the source and advise you of what actions you may take.
There is a flat rate charge for clearing a blockage that occurs on private property, should this be required. You should also call your insurance company as soon as possible and report any damage caused by the flooding. They will also advise you on how to proceed. Be mindful of your health and safety when cleaning up your flooded basement. Floodwater may be unsanitary, contain irritants, corrosive cleaning agents and possibly sharp objects. Electrical accidents can occur if water is in contact with appliances. If concerned, stay out of the basement and contact a professional to assist in or conduct the cleanup and sanitization of your basement.
Halton Region is now offering a one-time Basement Flood Prevention Subsidy, up to a maximum of $2,725.00, to assist:
For additional information on the Basement Flood Prevention Subsidy Program, or any other issues related to basement flooding, please contact the Program Coordinator Matt Stefanik at 905-825-6000 ext. 7918.