Item - 2025.PH23.14

The Planning and Housing Committee recommends that:

1. City Council request the General Manager, Toronto Water, and the Executive Director, Development Review, to consult with all relevant industry stakeholders, to identify risks and costs of the Foundation Drainage Policy and opportunities to improve upon it to ensure that the City’s interests in encouraging new housing starts are balanced with the objectives of the Policy, and report in the first quarter of 2026 on possible amendments to the Policy, including clear and specific criteria for exemptions to the Policy.

2. City Council request the General Manager, Toronto Water, to report through the appropriate Committee in the first quarter of 2026 on the feasibility of revising the manganese limit for discharging water into the City’s storm sewer system.

I am writing to request your support to have Staff review the City’s Foundation Drainage Policy (the “Policy”). Through working closely with City Staff from Toronto Water and Development Review, along with industry leaders, we have identified potential improvements to the Policy that could support the viability of certain development sites without compromising sewer capacity or water quality.

In November 2021, City staff implemented a Foundation Drainage Policy to preserve sewer capacity and meet growing demands for the City’s sewer systems by implementing a requirement that foundation drainage be managed on-site rather than being discharged to the City’s sewer system. The Policy applies to all development applications under the Planning Act, except for Committee of Adjustment applications, effective January 1, 2022.

The Policy, as currently applied and implemented, requires a technical investigation to determine if a proposed building foundation will be within groundwater.  Where there will be groundwater present, the project is required to manage the groundwater on-site.  This can be accomplished using watertight foundation construction. The foundations associated with watertight basements can impact the cost of a project, particularly smaller or mid-rise buildings. The financial implications make housing more expensive across Toronto and is contrary to the city’s objective to encourage more mid-rise development along Major Streets and Avenues.

It is time to evaluate the Foundation Drainage Policy and consider opportunities for improvement. This motion seeks to ensure that the objectives of the Policy are achieved without inappropriately undermining other important City goals, including encouraging new housing starts, reducing embodied carbon in new buildings, and promoting sustainable development in Toronto. The City has heard from industry professionals across many disciplines (geotechnical, hydrogeological, civil, structural, mechanical) who have identified concerns with the Policy and identified science and engineering-based opportunities to improve it, while still protecting the city’s interests.  

For example, a major opportunity identified by industry experts is reconsideration of the City’s Manganese limits in its sewer by-law.  Manganese is a naturally occurring element that poses no risk to humans or the environment at naturally occurring levels and is present in almost all ground water across the Greater Toronto Area and Ontario. The City's sewer By-law mandates an extremely low/almost zero limit for Manganese in water discharged to its storm sewer system. Accordingly, the Manganese limit effectively requires that groundwater must be discharged to the sanitary sewer, if it is to be discharge to a City sewer at all. It is worth investigating whether the City’s Manganese limit in its sewer by-law could be safely changed to create opportunities to meet the Policy’s objectives while better facilitating the development of housing and development in Toronto in an environmentally sustainable way, reducing embodied carbon in new buildings.

Thank you for your consideration of the accompanying recommendations.