Changes

[[File:Subsurface draw outlet.PNG|500px|thumb|Schematic of a reverse sloped subsurface draw outlet to help ensure cooler outflows occur from stormwater ponds (MOE, 2003).<ref>Ministry of the Environment. 2003. Stormwater Management Planning and Design Manual. March, 2003. ISBN 0-7794-2969-9. PIBS 4329e. https://dr6j45jk9xcmk.cloudfront.net/documents/1757/195-stormwater-planning-and-design-en.pdf</ref>]]

[[File:Subsurface draw outlet.PNG|500px|thumb|Schematic of a reverse sloped subsurface draw outlet to help ensure cooler outflows occur from stormwater ponds (MOE, 2003).<ref>Ministry of the Environment. 2003. Stormwater Management Planning and Design Manual. March, 2003. ISBN 0-7794-2969-9. PIBS 4329e. https://dr6j45jk9xcmk.cloudfront.net/documents/1757/195-stormwater-planning-and-design-en.pdf</ref>]]

There are several opportunities to mitigate thermal impacts both within the pond itself and/or implemented within the upstream drainage area (and the lands surrounding) of the pond.  Options shown in past studies to provide appreciable thermal mitigation benefits include (Van Seters and Dougherty, 2019).<ref>Van Seters, T., and Dougherty, J. 2019. Data Synthesis and Design Considerations for Stormwater Thermal Mitigation Measures. Sustainable Technologies Evaluation Program. Ontario. https://sustainabletechnologies.ca/app/uploads/2019/04/Thermal-Synthesis-Final.pdf</ref></ref>

There are several opportunities to mitigate thermal impacts both within the pond itself and/or implemented within the upstream drainage area (and the lands surrounding) of the pond.  Options shown in past studies to provide appreciable thermal mitigation benefits include (Van Seters and Dougherty, 2019).<ref>Van Seters, T., and Dougherty, J. 2019. Data Synthesis and Design Considerations for Stormwater Thermal Mitigation Measures. Sustainable Technologies Evaluation Program. Ontario. https://sustainabletechnologies.ca/app/uploads/2019/04/Thermal-Synthesis-Final.pdf</ref><br>

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====Subsurface Draw Outlets====

====Subsurface Draw Outlets====

'''Expected Performance'''

'''Expected Performance'''

*Relative to a surface draw outlet, the expected 95th percentile temperature reduction provided by a 2 m deep draw outlet for years with similar air temperatures is between 3 and 5⁰C.  

*Relative to a surface draw outlet, the expected 95th percentile temperature reduction provided by a 2 m deep draw outlet for years with similar air temperatures is between 3 and 5⁰C.  

*Water drained from outlets 2m below the surface will typically be less than 24°C at least 95% of the time.

*Water drained from outlets 2m below the surface will typically be less than 24°C at least 95% of the time.<br>

====Night Time Release Outlets====

====Night Time Release Outlets====