We addressed flooding and water quality problems at an unpermitted borrow pit in Temple Terrace, Florida. The site frequently overflowed during heavy rain, threatening nearby homes, roads, and natural areas. Our goal was to transform the borrow pit into a permitted stormwater pond that reduced flooding, treated stormwater, and protected people and the environment.
The borrow pit was located within a Federal Emergency Management Agency (FEMA) flood zone and lacked a legal outlet for safe water release during large storms. We analyzed site hydrology and runoff patterns, calculating runoff volumes for small and large storms, including 100-year events. We also assessed how future development would increase runoff and ensured our design complied with all local and state stormwater regulations.
We redesigned the borrow pit into a controlled stormwater pond with a smart water management system that lowered water levels before predicted storms to create storage capacity for incoming rainfall. This prevented flooding during heavy rainfall events. Extended detention times allowed sediments and pollutants to settle naturally, improving water quality. We redesigned a swale to convey treated water to a nearby wetland while minimizing soil erosion. Our final design met all stormwater and flood safety requirements. This project demonstrated that intelligent stormwater systems can effectively reduce flooding, enhance water quality, and protect adjacent communities and natural areas.