1. A combination of warm weather grasses, terrestrial and aquatic plants in and around the spring Stormwater Management Plan for College Springs Park Benjamin Snyder, Andrew Jeffery, and Brandon Copeland Biological Systems Engineering Department of Virginia Tech Problem Description Acknowledgements Dr. Mary Leigh Wolfe (Biological Systems Engineering) Dr. Gene Yagow (Biological Systems Engineering) Pollutant Recommended levels Baseflow Measurements Stormevent Measurements Total Nitrogen (TN) 0.69 mg/L *15.33 mg/L 4.79 mg/L Total Phosphorus (TP) 36.56 µg/L *247.67 µg/L2260 µg/L Total Suspended Solids (TSS) 30 mg/L **<1 mg/L214 mg/L Enhanced Vegetation EPA National nutrient recommendations for Eco-region IX ** As recommended by VADQS handbook Community Outreach Daylighting Stroubles Creek is impaired for benthic macroinvertebrates, with sediment identified as the primary stressor. College Springs Park is located in the Upper Stroubles Creek Watershed in Blacksburg, Virginia, which contains significant urban and agricultural land uses. Site Description 1.25 acre park 236 acre drainage area 27% impervious area Areas of interest Design Process Management practices where chosen based on water quality results and hydrologic analysis of the sub-watershed. Daylighting: Re-establishment of a once existing waterway Water quality swale: Vegetated channel that allows for infiltration into an engineered soil matrix Vegetation enhancement: Establishment of native plant species in and around a wetland Hydrologic analysis was performed using ArcGIS and TR-55 software, indicating peak discharge values of 1.20 and 3.19 m 3 /s for the 2-yr and 10-yr storm events respectively. Proposed Solutions 1)Wooded spring area 2)Piped stream under park 3)Berryfield drainage channel 1 3 2 A community brochure has been developed in conjunction with SEEDS and the Town of Blacksburg to educate residents about their watershed. Benefits / Potential Pollutant Removal Efficiencies Daylighting Re-establish stream corridor Decrease flow velocity via stream meandering Increased biological uptake Community Awareness Water Quality Swale TSS – 80% TP – 35% TN – 20 – 40% Vegetation Enhancement Erosion control Biological uptake Provide wildlife habitat Aesthetic value for community Components: Engineered Soil Matrix – 50% sand, 30% leaf mulch, 20% top soil Perforated underdrains – Two 4’’ (0.10m) corrugated PVC pipes Checkdams and Toe Protection – Height of 0.46m based on peak discharge of 10-yr storm event SpeciesAmountPrices ($)Total Indian Grass 5-7 lbs/ac11.49/lb$32.17 Eastern Gamma Grass @ 0.4 ac12.99/lb$36.37 Switch Grass = 2.8 lbs6.5/lb$18.20 Black-Eyed Susan 1-8 oz/ac24/lb$4.80 Maximillian Sunflower @ 0.4 ac9.95/lb$1.99 Annual Lespedeza = 3.2 oz1.70/lb$2.00 Partridge Pea 19.95/lb$3.99 Water Lotus 40 seeds6.95 / 10 seeds$27.80 Water Lilly20 / 5 seeds$80.00 Establishment of native vegetation around 0.4 ac spring area. Water Quality Swale Stream channel dimensions were based on downstream measurements: Wetted Perimeter: 1.28 m Area: 0.11 m 2 Velocity: 0.18 m/s Discharge: 0.068 m 3 /s Cost of Implementation: $45,069 Costs Construction: $3,280 Maintenance: $116/yr