Cost effective stormwater management strategies in response to climate change and urbanization

What is it about?

Surface runoff refers to the flow of water on the ground when it can no longer penetrate the soil. Increasing urban development and effects of climate change on rainfall will continue to increase surface runoff. It is thus important to take measures to contain this surplus and reduce its impact on the ecosystem. To this end, scientists applied a simple tool to simulate surface runoff in small watersheds (land that drains runoff into a water body) to assess stormwater management pathways (SMPs). The tool simulates the flow of runoff from land and soil map data using the curve number based watershed model (CWM). They also used the System for Urban Stormwater Treatment and Analysis Integration (SUSTAIN) model to assess costs involved in the two best management practice (BMP) categories: gray and green. The results showed that the cost of SMPs (infiltration trenches and bioretention) in present use will outweigh their benefits in the future owing to climate and urban changes. The scientists also found that gray BMPs (structures that focus on quickly removing stormwater from urban areas) were effective for flood control. On the other hand, green BMPs (those that restore ecological processes while regulating stormwater) were valued for their added benefits, like improving air quality and preserving ecosystems.

Featured Image

Photo by The Tampa Bay Estuary Program on Unsplash

Photo by The Tampa Bay Estuary Program on Unsplash

Why is it important?

Green and gray BMPs reduce surface runoff disasters like flooding that stem from climate change and urbanization. Weighing the pros and cons of BMPs offers key inputs to plan mitigation efforts. Most hydrologic models used in stormwater management are difficult to handle. A less complex model like CWM can help ease the process. CWM uses less complex input data and can even be set up for small watersheds. Thus, conducting a thorough analysis of BMPs can help assess the value of existing management practices. KEY TAKEAWAY: The choice of BMPs and the construction of SMPs in response to climate change and urban development constitutes the key to an effective flood protection strategy. This research relates to the following Sustainable Development Goals: • SDG 11: Sustainable Cities and Communities • SDG 13: Climate Action • SDG 15: Life on Land • SDG 6: Clean Water and Sanitation • SDG 9: Industry, Innovation, and Infrastructure