Hughes Associates A&E was selected to value-engineer a stormwater management system designed by another firm. We provided an alternative design that saved the owner $2,000,000 over the original system. The system contained both water quality quantity components used to meet the requirements of the Town of Blacksburg and the State of Virginia.
The underground system included weir walls, vortex and flap valves, up-flow filters and 1.9 million gallons of storage. We designed a head-building chamber during the development process of this system that was later patented by the client. Over 1,300 linear feet of 12-foot diameter spiral metal pipe, with approximately 30% of the pipe being perforated made up the system which is enveloped with a 360’ x 80 x 15’ heavy-duty LDPE/HDPE liner and backfilled with gravel. The system sits 10’ to 15’ below a surface parking lot and provides 5.51 acre-feet (240,000 cubic feet) of storage.