Changes

===='''Cooling Trenches'''====

===='''Cooling Trenches'''====

[https://sustainabletechnologies.ca/home/urban-runoff-green-infrastructure/thermal-mitigation/thermal-mitigation-system-evaluation/ Cooling trenches] typically consist of one or more geotextile wrapped perforated pipes embedded in a clear stone filled trench that is buried underground.  Water temperatures are reduced through heat transfer from the water passing through the trench to the stone and surrounding soils.  Cooling trenches may be installed downstream of the primary pond outlet or draw from a secondary orifice controlled outlet draining water from the pond at or below the permanent pool water level (e.g Van Seters and Graham, 2013<ref> Van Seters, T., Graham, C. 2013. Evaluation of an Innovative Technique for Augmenting Stream Baseflows and Mitigating the Thermal Impacts of Stormwater Ponds. Sustainable Technologies Evaluation Program, Toronto and Region Conservation Authority, Toronto, Ontario. https://sustainabletechnologies.ca/app/uploads/2013/08/Cooling-trench-final-2013a.pdf</ref>.; TRCA, 2020<ref>Toronto and Region Conservation Authority (TRCA) 2020. Evaluation of a Thermal Mitigation System on the Heritage at Victoria Square Pond in Markham. Toronto and Region Conservation Authority, Vaughan, Ontario. https://sustainabletechnologies.ca/app/uploads/2021/01/TM-Heritage-report-2021R.pdf</ref>). Further information about these innovative cooling trench features installed as part of the stormwater pond

[https://sustainabletechnologies.ca/home/urban-runoff-green-infrastructure/thermal-mitigation/thermal-mitigation-system-evaluation/ Cooling trenches] typically consist of one or more geotextile wrapped perforated pipes embedded in a clear stone filled trench that is buried underground.  Water temperatures are reduced through heat transfer from the water passing through the trench to the stone and surrounding soils.  Cooling trenches may be installed downstream of the primary pond outlet or draw from a secondary orifice controlled outlet draining water from the pond at or below the permanent pool water level (e.g Van Seters and Graham, 2013<ref name="example3"> Van Seters, T., Graham, C. 2013. Evaluation of an Innovative Technique for Augmenting Stream Baseflows and Mitigating the Thermal Impacts of Stormwater Ponds. Sustainable Technologies Evaluation Program, Toronto and Region Conservation Authority, Toronto, Ontario. https://sustainabletechnologies.ca/app/uploads/2013/08/Cooling-trench-final-2013a.pdf</ref>.; TRCA, 2020<ref>Toronto and Region Conservation Authority (TRCA) 2020. Evaluation of a Thermal Mitigation System on the Heritage at Victoria Square Pond in Markham. Toronto and Region Conservation Authority, Vaughan, Ontario. https://sustainabletechnologies.ca/app/uploads/2021/01/TM-Heritage-report-2021R.pdf</ref>). Further information about these innovative cooling trench features installed as part of the stormwater pond

operation design in two sites located in Markham, ON. visit the [https://sustainabletechnologies.ca/home/urban-runoff-green-infrastructure/thermal-mitigation/thermal-mitigation-system-evaluation/ STEP project page]. The permanent pool of stormwater management ponds acts as a heat sink during the summer, resulting in warmer summer discharges during both storm and baseflow conditions.  

operation design in two sites located in Markham, ON. visit the [https://sustainabletechnologies.ca/home/urban-runoff-green-infrastructure/thermal-mitigation/thermal-mitigation-system-evaluation/ STEP project page]. The permanent pool of stormwater management ponds acts as a heat sink during the summer, resulting in warmer summer discharges during both storm and baseflow conditions.  

*Based on case studies reviewed, primary outlet trenches without groundwater interaction may provide summer temperature cooling of the warmest flows by roughly 1 to 3⁰C if the trench storage volume is equal to or greater than 5% of the runoff volume discharged from the pond during the 25 mm event.

*Based on case studies reviewed, primary outlet trenches without groundwater interaction may provide summer temperature cooling of the warmest flows by roughly 1 to 3⁰C if the trench storage volume is equal to or greater than 5% of the runoff volume discharged from the pond during the 25 mm event.

[[File:Cooling Trenches excavated.jpg|450px|thumb|Another image of a cooling trench being built with two parallel trenches that contain [[Choker layer|pea gravel]] and two sets of 200 mm perforated [[pipes]] wrapped in filter fabric. (Van Seters and Graham, 2013<ref> Van Seters, T., Graham, C. 2013. Evaluation of an Innovative Technique for Augmenting Stream Baseflows and Mitigating the Thermal Impacts of Stormwater Ponds. Sustainable Technologies Evaluation Program, Toronto and Region Conservation Authority, Toronto, Ontario. https://sustainabletechnologies.ca/app/uploads/2013/08/Cooling-trench-final-2013a.pdf</ref>. Photo Source: [[Acknowledgements|Doug McGill]]]]

[[File:Cooling Trenches excavated.jpg|450px|thumb|Another image of a cooling trench being built with two parallel trenches that contain [[Choker layer|pea gravel]] and two sets of 200 mm perforated [[pipes]] wrapped in filter fabric. (Van Seters and Graham, 2013<ref name="example3" />. Photo Source: [[Acknowledgements|Doug McGill]]]]

===='''Infiltration Systems'''====

===='''Infiltration Systems'''====