Forecast-Driven Real-Time Control of Detention Ponds: Impacts on Hydrology, Channel Erosion, and Pollutant Removal

Abstract Real-time control (RTC) systems are increasingly being integrated into various stormwater control measures, including detention ponds, to address inefficiencies stemming from static designs based on a single design storm event. Existing studied RTC systems for detention ponds are typically rule-based and site-specific, and their performance evaluations have largely focused on peak flow reduction and water quality improvements, while their effects on receiving stream channel response have been largely overlooked. In this study, we developed a novel optimization-based RTC system to operate a gate on the outflow pipe of a detention pond. This system utilizes real-time pond monitoring and weather forecast data to make adaptive decisions and is designed to be non-site-specific. Hydrologic and hydraulic simulations were conducted using hydrologic and hydraulic models of the Caldwell Creek watershed in Charlotte, NC, to evaluate the effectiveness of this optimized RTC system. The goal was to assess its performance in reducing peak flows, enhancing channel stability, and improving total suspended solids (TSS) removal. The optimized RTC system demonstrated the ability to reduce peak flows by up to 54%. As a result of the lower peak flows, erosion and deposition are modeled to decrease by up to 30%, contributing to improved channel stability. Additionally, the increased hydraulic retention time provided by the RTC system resulted in up to a <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="2 times" display="inline" overflow="scroll"> <mml:mn>2</mml:mn> <mml:mspace width="-0.2em"/> <mml:mo>×</mml:mo> </mml:math> increase in TSS removal efficiency compared to a static detention pond design. While the simulation results are promising, field implementation and real-world testing are necessary to validate the system’s performance.