Halton Region mitigates risk - Flood prevention

NRU
July 15, 2015
By Leah Wong

With extreme weather events becoming more common, and with them increased urban flooding, municipalities are challenged to mitigate basement flooding. Halton Region’s response is to prepare a region-wide strategy to disconnect residential downspouts and weeping tiles.

The recommendations from public works commissioner Jim Harnum come almost a year after a major storm caused the flooding of several thousand homes in the City of Burlington. While it is difficult to accurately predict when extreme weathers will occur and where they will impact, Harnum’s report says events like the August 2014 storm show the need for municipalities to adapt to changing weather patterns.

For Halton one of the best ways to prepare for extreme weather events is to work on getting water out of the wastewater system Harnum told the planning and public works committee last week.

“We’re trying to get people to get rainwater out of the sewer,” said Harnum. “If we can get water out we’re in better shape and ahead of the game.”

In November 2014 regional council retained GM BluePlan Engineering to review its sanitary sewer system and undertake a region-wide basement flooding mitigation study. The study showed there were no deficiencies within the wastewater system significant enough to cause flooding during regular rain events. Sanitary surcharging occurs only under extreme storm events.

To prevent system overloading in extreme weather events, the region is asking residentsto voluntarily disconnect their downspouts and weeping tiles and offering a 100 per cent subsidy for participants. Harnum said one of the challenges with disconnection programs is getting the public to participate.

“It is almost impossible to force people to get their weeping tiles disconnect,” he said, adding that even in Toronto where the disconnection program is mandatory there is a struggle to get residents to cooperate.

Staff will be bringing forward recommended pipe remediation projects for sections of the system that have showed significant infiltration or active leaks, which require funding through the 2016 budget. The timing of these projects will coincide with regional and municipal road repairs. It is expected that the 10-year implementation plan will cost $88.9-million. During the 2016 budget process council will be asked to fund the plan through a special surcharge through to 2025.

Some regional councillors raised issue with a region-wide surcharge that would impact all residents in Halton, when owners of newer homes have already paid for infrastructure upgrades through development charges. However, staff recommend a system-wide approach. Burlington councillor Jack Dennison reminded his colleagues that new homes may also be connected to older infrastructure in the system.

“The system itself is the issue,” he said.