Flooding in Brantford: Behind the Dikes on the Grand, and the Basements the Dikes Do Not Reach

The river, the sewers and the melt

River flooding announces itself: the Grand River Conservation Authority issues flood warnings, ice jams form at the bends, and the City monitors the dikes and issues evacuation orders for the neighbourhoods inside the bend; in 2018 the water rose faster than the forecast. Sewer backup arrives at the floor drain, a basement toilet or the laundry standpipe during or just after heavy rain and smells like sewage; the older streets near the river and downtown are most exposed. Groundwater arrives clear at the wall-floor joint and through the brick foundations of the 1880s houses in the melt and after long rains, and the water table inside the bend rises with the river.

Photograph where the water first appeared and when. A river warning, a storm and a smell, or a melt and clear water each point to a different fix.

What the dikes protect, and what the fixes do

The City of Brantford owns and maintains the dike system along the Grand, and it is designed to hold a defined flood; 2018 showed the margin is not infinite, and the City and the GRCA have been studying upgrades since. Inside the dikes, the water table still rises with the river, and a basement in Eagle Place can flood from below while the dike holds. A sump pump with a pit and a battery backup handles that groundwater up to a point; a backwater valve is a one-way flap on the sanitary lateral that closes when the sewer surcharges so sewage cannot flow back into the house. Neither stops the river if the dike is overtopped.

In the flood plain, the tools are the GRCA’s and the City’s flood-proofing guidance, keeping valuables and utilities off the basement floor, an evacuation plan and insurance. The City and the Region have offered programs for backwater valves and related protective plumbing at times; check the current page before signing a quote.

• GRCA flood-plain map and the City’s dike map checked for your address
• City’s current program checked for eligibility
• Licensed plumber and City of Brantford plumbing permit number
• Camera inspection recording and locate
• Sump pump tested, backup and alarm

Who owns which pipe

Brantford runs its own water and wastewater utility, so the City owns both the sanitary and the storm sewers beyond your property line as well as the dikes; the lateral on your property is yours. A camera inspection with a locate tells you which side a break or blockage is on. Keep the recording; an insurer will want it, and sewer backup and overland water are usually separate add-ons on an Ontario policy. After 2018, overland flood coverage inside the bend became harder to get; ask your broker what is available at your address.

Old brick, the melt and the next jam

Eagle Place, Holmedale and Old West Brant have 1880s to 1920s brick houses with clay weeping tile long since silted and foundations that groundwater passes through; waterproofing there is exterior drainage and a membrane where the lot allows, interior drainage to a sump where it does not, and a basement kept as storage rather than living space. In February and March, watch the GRCA’s ice-jam warnings, test the sump pump, clear the discharge line and the window wells, and know the City’s evacuation routes.