Current Basement Flooding Investigation Environmental Assessment Studies
This site was last updated August 30, 2013
Welcome to the homepage for information on Basement Flooding Study Projects.
On August 19, 2005, the City of Toronto experienced a severe storm event that resulted in the flooding of many residents homes, erosion in ravines and watercourses, and damage to City infrastructure such as roads, bridges, culverts and sewers. Toronto Water received over 4,200 basement flooding complaints, the majority of which occurred north of Highway 401. It was within this area where the storm exceeded a 100 year event and experienced over 150 mm (6 in.) of rainfall in a three (3) hour period.
In response, City Council approved the "Basement Flooding Work Plan" to undertake investigations to alleviate future flooding in 34 basement flooding areas.
34 basement flooding Study Areas have been identified. Please select one of the following active projects:
- Study Area 1 (East York – O'Connor Drive & St Clair Ave East)
- Study Area 2 (Leaside)
- Study Areas 4 & 5 (Humber River / Black Creek)
- Study Area 6 (Humber River / Black Creek)
- Study Areas 13 & 15 (Jane Street / Sheppard Avenue West)
- Study Area 17, 18, 19 (Allen Road / Highway 401)
- Study Area 20 (Lawrence Park Neighbourhood)
- Study Area 22 (Victoria Park Avenue / Lawrence Eglinton)
- Study Area 21 – 23 (Don Mills Rd / DVP / York Mills Rd)
- Study Area 24 – 27 (Yonge Street/Sheppard Avenue East)
Reported evidence of basement flooding included:
- Water backed up from floor drains;
- Overloaded storm and sanitary sewers;
- Leakage through cracks in basement walls;
- Flood water from windows and/or doors; and
- Heaved basement floors
Possible causes of the flooding were attributed to:
- Surcharge of sanitary sewers caused by infiltration/inflow;
- Surcharge of storm sewers;
- Surface flooding;
- High ground water table; and
- Blockage in sewers and street catch basins.
The Environmental Assessment (EA) Process
Each study is being carried out in accordance with the Class EA requirements set out in the Municipal Class Environmental Assessment (October 2000, as amended in 2007). The Class EA process will provide members of the public and interest groups with an opportunity for input at key stages of this study. The study will define the problem, consider and evaluate alternative solutions, assess impacts of the proposed solutions and identify measures to lessen any adverse impacts.
Upon completion of each study, a Project File will be submitted to the Ministry of the Environment and will be available for a 30-day public review.
- Basement Flooding General Information
- Homeowner Measures (PDF)
- Tips for the Homeowner (PDF)
- Causes of Basement Flooding Presentation (PDF)
- Glossary of Terms (PDF)
- Remedial Solutions Presentation (PDF)
Public input and comments are welcome and will be considered in the planning of these studies. If you are interested in more information or would like to be added to the project mailing list for any of the on-going Environmental Assessment Studies, please click on the study area you are interested in above for more details.
With the exception of personal information, all comments will become part of the public record.
Completed Studies and Construction of Mitigation Measures
Studies for the following surface and basement flooding areas are now complete. Access the full Environmental Study Reports that describe the recommended solutions for each Study Area.
The City launched a multi-year Basement Flooding Protection Program to implement the solutions and help prevent basement and surface flooding.
Construction commenced in a number of neighbourhoods across the City in the fall of 2009. Work consists of storm and/or sanitary sewer upgrades, construction of dry ponds and underground storage tanks, as well as other service improvements.
What is happening in my neighbourhood?
Select your ward to find out what is planned for your neighbourhood in 2012.