Changes

[[File:Screenshot 2025-08-27 151300.png|400px|thumb|right|link=https://storymaps.arcgis.com/collections/8c517b063c81449d8fba71ca02d4278f?item=6|Maps showing predicted increases in temperature and precipitation for Toronto Region over the 21st Century under the high GHG emission scenario. Adapted from TRCA (2025)<ref>TRCA. 2025. Watershed and Ecosystems Reporting Hub. https://storymaps.arcgis.com/collections/8c517b063c81449d8fba71ca02d4278f?item=6</ref>. Click on the image to go to TRCA's Watershed and Ecosystems Reporting Hub and explore future climate trends.]]

[[File:Screenshot 2025-08-27 151300.png|500px|thumb|right|link=https://storymaps.arcgis.com/collections/8c517b063c81449d8fba71ca02d4278f?item=6|Maps showing predicted increases in temperature and precipitation for Toronto Region over the 21st Century under the high GHG emission scenario. Adapted from TRCA (2025)<ref>TRCA. 2025. Watershed and Ecosystems Reporting Hub. https://storymaps.arcgis.com/collections/8c517b063c81449d8fba71ca02d4278f?item=6</ref>. Click on the image to go to TRCA's Watershed and Ecosystems Reporting Hub and explore future climate trends.]]

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==Overview==

==Overview==

==Climate change challenges for grey infrastructure & SWM==

==Climate change challenges for grey infrastructure & SWM==

[[File:Screenshot 2025-08-28 143837.png|450px|thumb|right|Traditional grey infrastructure focused on conveying stormwater to end-of-pipe storage facilities is not resilient to climate change. Urban areas should be retrofitted with green infrastructure which uses a distributed network of stormwater features to [[filtration|filter]] and [[infiltration|infiltrate]] runoff at the source. Image adapted from Pennsylvania Wilds (2021) <ref>Pennsylvania Wilds. 2021. Just what is green infrastructure? https://pawilds.com/just-what-is-green-infrastructure/</ref>.]]

[[File:Screenshot 2025-08-28 143837.png|500px|thumb|right|Traditional grey infrastructure focused on conveying stormwater to end-of-pipe storage facilities is not resilient to climate change. Urban areas should be retrofitted with green infrastructure which uses a distributed network of stormwater features to [[filtration|filter]] and [[infiltration|infiltrate]] runoff at the source. Image adapted from Pennsylvania Wilds (2021) <ref>Pennsylvania Wilds. 2021. Just what is green infrastructure? https://pawilds.com/just-what-is-green-infrastructure/</ref>.]]

Stormwater dynamics are strongly influenced by land use and rainfall patterns, making them vulnerable to both climate change and [[Urbanization|urbanization]]. Canadian cities are experiencing climate change impacts at rates often exceeding the global average, as Canada is warming nearly twice as fast as the rest of the world (Bush & Lemmen, 2019)<ref>Bush, E., & Lemmen, D. 2019. Canada’s changing climate report.</ref>. Traditional stormwater systems that focus on efficiently conveying stormwater were designed based on historical climate conditions. However, urbanization and climate change have intensified surface runoff by way of more frequent and intensive rainfall occurrences and increased [[Natural drainage|impermeable]] land cover. This in turn creates challenges for urban drainage systems that lack sufficient adaptive capacity (Wang et al., 2023)<ref>Wang, M., Liu, M., Zhang, D., Zhang, Y., Su, J., Zhou, S., Bakhshipour, A., Tan, S. 2023. Assessing hydrological performance for optimized integrated grey-green infrastructure in response to climate change based on shared socio-economic pathways. Sustainable Cities and Society, Volume 91. https://doi.org/10.1016/j.scs.2023.104436 </ref>. Given these interconnected pressures, [[Definition of Low Impact Development|green infrastructure]] is increasingly essential for reducing flood risk, safeguarding [[Water quality|water quality]], and strengthening urban resilience. LID builds climate resilience by supplementing large [[SWM ponds|end-of-pipe ponds]] with a distributed network of smaller-scale stormwater features throughout the catchment to retain and treat runoff as close to the source as possible (Canada in a Changing Climate, 2018)<ref>Canada in a Changing Climate. 2018. Evaluation of Retrofitted Low Impact Development Practices for Stormwater Management at an Industrial Site. https://changingclimate.ca/map/evaluation-of-retrofitted-low-impact-development-practices-for-stormwater-management-at-an-industrial-site/</ref>.

Stormwater dynamics are strongly influenced by land use and rainfall patterns, making them vulnerable to both climate change and [[Urbanization|urbanization]]. Canadian cities are experiencing climate change impacts at rates often exceeding the global average, as Canada is warming nearly twice as fast as the rest of the world (Bush & Lemmen, 2019)<ref>Bush, E., & Lemmen, D. 2019. Canada’s changing climate report.</ref>. Traditional stormwater systems that focus on efficiently conveying stormwater were designed based on historical climate conditions. However, urbanization and climate change have intensified surface runoff by way of more frequent and intensive rainfall occurrences and increased [[Natural drainage|impermeable]] land cover. This in turn creates challenges for urban drainage systems that lack sufficient adaptive capacity (Wang et al., 2023)<ref>Wang, M., Liu, M., Zhang, D., Zhang, Y., Su, J., Zhou, S., Bakhshipour, A., Tan, S. 2023. Assessing hydrological performance for optimized integrated grey-green infrastructure in response to climate change based on shared socio-economic pathways. Sustainable Cities and Society, Volume 91. https://doi.org/10.1016/j.scs.2023.104436 </ref>. Given these interconnected pressures, [[Definition of Low Impact Development|green infrastructure]] is increasingly essential for reducing flood risk, safeguarding [[Water quality|water quality]], and strengthening urban resilience. LID builds climate resilience by supplementing large [[SWM ponds|end-of-pipe ponds]] with a distributed network of smaller-scale stormwater features throughout the catchment to retain and treat runoff as close to the source as possible (Canada in a Changing Climate, 2018)<ref>Canada in a Changing Climate. 2018. Evaluation of Retrofitted Low Impact Development Practices for Stormwater Management at an Industrial Site. https://changingclimate.ca/map/evaluation-of-retrofitted-low-impact-development-practices-for-stormwater-management-at-an-industrial-site/</ref>.

==Adapting to climate change using LID==

==Adapting to climate change using LID==

[[File:Adaptation vs. Mitigation ICLEI.jpg|400px|thumb|right|Adaptation and mitigation are two complementary strategies for addressing climate change: mitigation focuses on reducing greenhouse gas emissions to lessen future climate change, while adaptation involves adjusting to the current and future effects of climate change that are already happening (Regional District of Nanaimo, ND)<ref>Regional District of Nanaimo. ND. Climate Change, Adaptation and Mitigation. http://rdn.bc.ca/climate-change-adaptation-and-mitigation</ref>.]]

[[File:Adaptation vs. Mitigation ICLEI.jpg|500px|thumb|right|Adaptation and mitigation are two complementary strategies for addressing climate change: mitigation focuses on reducing greenhouse gas emissions to lessen future climate change, while adaptation involves adjusting to the current and future effects of climate change that are already happening (Regional District of Nanaimo, ND)<ref>Regional District of Nanaimo. ND. Climate Change, Adaptation and Mitigation. http://rdn.bc.ca/climate-change-adaptation-and-mitigation</ref>.]]

[[File:Screenshot 2025-09-05 163005.png|500px|thumb|right|LID can help offset climate change impacts in urban environments (IISD, 2021) <ref>International Institute for Sustainable Development. 2021. Natural Infrastructure Solutions for Climate Resilience. https://www.iisd.org/articles/explainer/natural-infrastructure-solutions-climate-resilience</ref>.]]

[[File:Screenshot 2025-09-05 163005.png|500px|thumb|right|LID can help offset climate change impacts in urban environments (IISD, 2021) <ref>International Institute for Sustainable Development. 2021. Natural Infrastructure Solutions for Climate Resilience. https://www.iisd.org/articles/explainer/natural-infrastructure-solutions-climate-resilience</ref>.]]

[[File:Screenshot 2025-08-26 165331.png|500px|thumb|right| A variety of LID features distributed across a catchment addresses climate vulnerabilities more effectively than traditional grey infrastructure. Image adapted from the CT Stormwater Quality Manual (2025) <ref> CT Stormwater Quality Manual. 2025. LID Planning and Design Process. https://ctstormwatermanual.nemo.uconn.edu/lid-planning-and-design/</ref> ]]

[[File:Screenshot 2025-08-26 165331.png|500px|thumb|right| A variety of LID features distributed across a catchment addresses climate vulnerabilities more effectively than traditional grey infrastructure. Image adapted from the CT Stormwater Quality Manual (2025) <ref> CT Stormwater Quality Manual. 2025. LID Planning and Design Process. https://ctstormwatermanual.nemo.uconn.edu/lid-planning-and-design/</ref> ]]