Reducing urban phosphorus loads to Lake Simcoe through an innovative new offsetting program

Session: 56. - Science for a Healthy Lake Simcoe

Ben Longstaff, Lake Simcoe Region Conservation Authority, [email protected]
Mike Walters, Lake Simcoe Region Conservation Authority, [email protected]
Rob Baldwin, Lake Simcoe Region Conservation Authority, [email protected]

Abstract

Reducing phosphorus (P) loads to Lake Simcoe required an innovative new approach to mitigate impacts of historical and on-going urbanization. Elevated urban P loads can largely be attributed to inadequate and poorly maintained stormwater management facilities. The legacy of poor stormwater management has resulted in a massive infrastructure and maintenance deficit for which there was no identifiable financial solution. In response to this challenge a P offsetting program based on the concept of a ‘zero export policy’ has been established. With an additional 9km2 of the watershed slated for development by 2031, the zero export policy requires all new and re-development to have no P discharge. If zero onsite P discharge cannot be achieved then a financial “offset” for the outstanding loads is charged to the developer. Implementation of the program is driving innovation in LID implementation in new developed areas and provides significant funding to retrofit existing urban areas to reduce existing P loading.  Understandably there is significant scrutiny and interest in the program from industry, government and Lake Simcoe stakeholders; as such failure to deliver the offsets is not an option. This presentation will highlight key elements of program, its formation and approaches to achieving the P offsets.

1. Keyword
phosphorus

2. Keyword
management

3. Keyword
urban watersheds

4. Additional Keyword
Offset