Collins Hill Library Stormwater BMP Retrofit Design, Gwinnett County Dept. of Water Resources, Lawrenceville, GA

Gwinnett County Department of Water Resources partnered with the Collins Hill Library to develop a plan for making stormwater improvements at the site. After evaluation of the site by county and WK Dickson staff, different BMPs including rainwater harvesting, bioretention, enhanced dry swales, permeable pavement and regenerative stormwater conveyance, were selected. The existing dry detention pond was also improved to include additional volume for extended release of the water quality and channel protection volumes bypassing the other BMP measures being implemented. The BMP improvements included a permeable recycled rubber trail and amphitheater for educational opportunities around the bioretention areas for local students from the nearby schools. The improvements also allowed the County to dress up several areas with native plants, eliminate ponding and drainage issues, and make improvements to a failing portion of their parking lot.

The project includes site specific management manuals for each of the BMPs to help train facility staff on their maintenance and upkeep. Monitoring opportunities are also being considered to provide long-term information on performance and application of the different water quality and runoff reduction measures.