Actionable Stormwater Platform - Implementation of a Digital Twin to Enhance Resilience

The Actional Stormwater Platform (ASP) is a central component of the City of Portsmouth's flood resilience strategy, addressing chronic stormwater and tidal flooding challenges. ASP is a cloud-based digital twin of the city's stormwater collection system, providing hourly inundation forecasts with a five-day lead time. It builds on Portsmouth's recent efforts to develop a citywide stormwater collection model using the US Environmental Protection Agency's Stormwater Management Model (SWMM) and to implement a digital twin that enhances system operations and urban resilience. The ASP integrates Multi-Radar/Multi-Sensor System (MRMS) gauge-adjusted radar rainfall data and rainfall forecasts from multiple weather models with coastal water level forecasts from the Storm Surge and Tide Operational Forecast System (STOFS). These inputs are used as boundary conditions for the SWMM model, which produces real-time stormwater inundation forecast maps for the city. Forecast outputs are presented through two cloud-based dashboards, offering city officials and stakeholders actionable insights on inundation forecasts, upcoming extreme rainfall and high tide events, and stormwater system performance. The ASP enables Portsmouth to adopt a proactive approach to extreme and nuisance storm events, enhancing the efficiency of emergency management efforts, improving storm preparation, and supporting the evaluation of infrastructure improvements and maintenance activities. Currently, the ASP covers one-third of Portsmouth's stormwater service area, with plans to expand citywide within the next year. This presentation will detail the development of the ASP, including its Python-based library, SWMM model, and forecast datasets, while also reviewing its performance during two historical storm events. Attendees will gain insights into the benefits and applications of digital stormwater twins, such as the ASP, as well as the technical challenges and considerations involved in creating similar platforms.