Challenge

The Indian Acres / Lake Pocahontas project involved improvements to the dam’s emergency spillway in Spotsylvania Courthouse, Virginia. The project called for an armoring solution that could provide erosion protection for this critical infrastructure while also delivering a natural appearance that complemented the surrounding environment. 

The emergency spillway serves a high-hazard dam measuring 54 feet in height with storage of 1,273 acre-feet. The design also incorporated a stilling basin at the lower end of the spillway to support the overall hydraulic design. 

Solution 

HydroTurf® CS was selected to armor the emergency spillway while preserving the site’s natural aesthetic. The system combines a geomembrane, engineered synthetic turf, and HydroBinder® cementitious infill to provide a durable, erosion-resistant revetment for critical hydraulic applications. Recognized by VA DCR as an acceptable overtopping technology, HydroTurf CS delivers hard-armoring performance with the appearance of natural turf. 

Result

During construction of the stilling basin, groundwater was encountered, presenting an unexpected field condition that required modification of the original design approach. The HydroTurf CS design was adapted to accommodate the observed groundwater conditions while maintaining the intended spillway armoring and erosion-protection strategy. 

The completed project incorporated 49,120 square feet of HydroTurf CS along the emergency spillway, providing an engineered, erosion-resistant surface for this critical hydraulic application. The finished system delivers the performance characteristics of hard armor while maintaining the natural aesthetic desired for the site.