| 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> 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. |