About this Event
Presentation Description- The City of Lancaster, Pennsylvania implemented an innovative water quality improvement project at Long’s Park to reduce stormwater pollutant loads as part of its Chesapeake Bay Pollutant Reduction Plan. The project targets nitrogen, phosphorus, and sediment reductions in runoff entering Little Conestoga Creek, ultimately benefiting the Chesapeake Bay ecosystem. The system features a pump station that circulates water from Long’s Pond through a constructed natural treatment system (NTS) comprising a forebay with floating wetland islands (FWIs), an iron-enhanced media filter (IEMF), and two sequential marshes. NTS are engineered ecosystems that leverage biological, physical, and chemical processes for cost-effective water treatment with minimal energy use and residuals compared to conventional systems. The forebay captures the first flush of stormwater, removing solids and associated pollutants. FWIs improve hydraulics and nutrient removal while providing wildlife habitat. The IEMF promotes phosphate removal via iron oxidation and enhances nitrification. Downstream marshes further polish water through solids retention, denitrification, phosphorus uptake, and ecological benefits such as mosquito control. Treated water returns to Long’s Pond, reducing eutrophication through improved flushing. Public engagement was integral to the design, incorporating trails, a boardwalk, and educational signage to create an interactive experience for visitors. The Soil-Plant-Atmosphere-Water (SPAW) model guided system sizing using 24 years of climatic data, ensuring capacity for a 100-year storm event. Modeling predicts an average inflow of 166,558 liters per day and significant pollutant reductions: 9 kg phosphorus, 45 kg nitrate, and 5,443 kg total suspended solids annually—equating to 50%, 32%, and 95% reductions, respectively. This presentation will share lessons learned from design, construction, and maintenance, along with initial performance data demonstrating the effectiveness of natural treatment systems in urban stormwater management.
Presenter Description- Allison Tritschler is a professional engineer and Senior Technologist in Natural Treatment Systems at Jacobs. A native Floridian and a double Florida Gator grad in environmental engineering, her passion and love for the water comes naturally. Allison has over 12 years of experience in natural treatment systems, constructed wetlands, and beneficial reuse projects across the state, country, and the globe.
Event venue & nearby stays
Hurricane BTW, 8181 Northwest 39th Avenue, Gainesville, United States
Concerts, fests, parties, meetups — all the happenings, one place.