Location: Hydrology and Remote Sensing LaboratoryTitle: Stormwater management adaptation pathways under climate change and urbanization
|KHAN, I.M. - University Of Maryland|
|HUBACEK, K. - University Of Groningen|
|BRUBAKER, K. - University Of Maryland|
|SUN, L. - University Of Maryland|
Submitted to: Frontiers in Environmental Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/2/2022
Publication Date: N/A
Interpretive Summary: Negative hydrologic consequences to the environment from urbanization are a concern that is addressed by stormwater best management practices (BMPs). These BMPs may be “gray” (conventional, structural drainage solutions) or “green” (newer, alternative development design or nature-based solutions). With future urbanization and climate change, more stormwater BMPs will be needed to manage increased runoff and limit additional environmental degradation. Presented here is a simple, curve number-based watershed model to simulate stormwater flows facing a portfolio of BMPs employed to manage runoff in small watersheds. Our findings indicate that future gray BMP alternatives are most cost effective. These findings point to a lack of proper valuation of co-benefits realized by green BMPs, indicating a need to place accurate economic valuation on all forms of ecosystem services.
Technical Abstract: Urban runoff volumes and flow peaks are likely to increase in the future owing to climate change-driven effects on rainfall and continued urbanization. Actionable planning estimates that anticipate these impacts are needed to assess storm stormwater management infrastructure requirements and to minimize impacts on ecosystem services. This study captures the complexity of urban catchment models for flow simulation and quantifies green infrastructure’s added value in moderating impacts on small watersheds. This study presents a planning-level simple flow simulation tool and quantifies benefits of green stormwater management practices in small watersheds. Flow simulation is performed using a curve number-based watershed model (CWM). A portfolio approach is used to assess cost-optimal stormwater adaptation pathways considering a suite of alternative stormwater practices including both gray and green infrastructure. The CWM provides actionable information for medium to highly urbanized watersheds with percent bias less than 30% for highly urbanized watersheds. Considering projected future stormwater needs, analysis of multiple stormwater management approaches shows that green stormwater management alternatives are less cost optimal than gray infrastructure at small watershed scales. These results suggest possible use of CWM for quick planning-level flow estimates and analysis of more green practices for cost optimal alternatives.