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Line 95: [[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]]]]
→Cooling Trenches
*Secondary pond outlets that drain water from 0.5 m below the permanent pool elevation to cooling trenches can help to reduce or eliminate the long duration and very warm interevent flows.
*Secondary pond outlets that drain water from 0.5 m below the permanent pool elevation to cooling trenches can help to reduce or eliminate the long duration and very warm interevent flows.
*Trenches may incorporate an infiltration function to help further reduce thermal loads if native soils and groundwater levels are suitable.
*Trenches may incorporate an infiltration function to help further reduce thermal loads if native soils and groundwater levels are suitable.
'''Expected Performance'''
'''Expected Performance'''
*Performance of primary outlet cooling trenches is highly variable due to differences in cooling trench sizing, design, initial water temperature and degree of groundwater interaction
*Performance of primary outlet cooling trenches is highly variable due to differences in cooling trench sizing, design, initial water temperature and degree of groundwater interaction
*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.<br>
*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.<br>
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[[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]]]]
===='''Infiltration Systems'''====
===='''Infiltration Systems'''====