(Photo credit: Toronto Star)
Open Data TO: This post is part of a series based on City of Toronto open datasets. Visit their open data portal here.
Between 2013 and June 2015, waste and ground water flooded 1,422 basements in Ward 11 (York South – Weston), the region hit hardest in Toronto. The area is located west of Yonge Street, which is where the vast majority of flooding occurred according to data shared by the City of Toronto.
Closer to the downtown core, the Danforth (Wards 29 and 30) and the Beaches (Wards 31 and 32) also had high concentrations of flooding. Ward 39, Scarborough – Agincourt, had the fewest flooded basements with only 99.
A number of factors underlie the problem:
- Storm or ground water can seep into homes when there are cracks in the foundation, basement walls, or basement windows.
- Poor lot grading or drainage, overflowing eaves troughs, and leaking or plugged downspouts can also result in flooding.
- Waste water can back up into properties through floor drains, toilets, sinks, showers, and laundry fixtures located in the basement.
- A sewer backup can also result from a blocked connection between the home and the main sewer in the street or when the sewer system becomes overwhelmed with storm water.
Mother Nature is also a major factor: The powerful storm that hit Toronto in July 2013 dumped an unprecedented volume of water in a short period of time, overwhelming the city’s drainage system and leading to a costly cleanup.
Between 2013 and 2014, a number of wards have significantly decreased the incidents of basement flooding: Wards 11 (York South – Weston), 2 (Etobicoke North), and 4 (Etobicoke Centre) cut the number of cases by more than half. The largest improvement was seen in Ward 3 (also Etobicoke Centre), which went from 802 in 2013 to 113 in 2014, a decrease of 86%.
The City of Toronto provides a Basement Flooding Protection Subsidy Program that grants up to $3,400 to homeowners for flood protection devices. Other preventative measures can be found here.