Lake Anna, near Belmont, Va., 70 miles (113 km) south of Washington, D.C., is one of the largest freshwater inland reservoirs in the state. The lake covers 13,000 acres (5,300 ha), making it a popular destination for sailing, waterskiing and sportfishing.
Waterfront homes enjoy spectacular views and unlimited access to the lake, but the landscape of shorefront property can pose some unique geotechnical challenges. Owners of a house situated atop a steep slope needed a safe and reliable access path from their home to their boathouse at the bottom of the hill. To accomplish this, they needed to add steps, retaining walls and a stone cart path that would blend into the natural landscape.
The steep 2:1 slope presented a challenge to the construction of the cart path. The property owners worked with the contractor to devise a plan for this project by first addressing the steep grade. The contractor proposed cutting back the earth to lessen the pitch of the downslope, then moving the excavated soil to the bottom of the hill where it would be graded to create a flat parking lot for carts.
The site contractor first began by removing vegetation from the face of the hillside, then made an 11 x 9 foot (3.4 x 2.7 m) cut into the slope that began 350 feet (107 m) from the top driveway, and extended down the hill to the proposed flat landing area. The excavated soil was then used to level the 15 x 15 foot (4.6 x 4.6 m) parking lot. This method reduced the grade to a 2.5:1 slope. After excavating the cart path, the bottom of the slope was hard armored with large riprap stone. On the backside of the cart path, the contractor built a seven-foot (2.1-m) block retaining wall to support the upper yard and provide structure above the cart path.
Geocells stabilize the hillside cart path
The newly formed cart path required a long-term solution to stabilize the surface and prevent erosion. Colonial Construction Materials, a local material provider, recommended Presto o Geosystems’ GEOWEB 3D Soil Stabilization System to create a stable pathway from the main house to the boathouse.
Along the pathway, contractors installed 3,220 square feet (299 m2) of four-inch (102-mm) deep, mid-cell GEOWEB (GW30V). Mechanical joints were secured using patented Presto ATRA Key geocell connector, and the entire system was anchored into place using 12-inch (305-mm) rebar stakes capped with ATRA Stake Clips. Once anchored into place, crews infilled the system with decorative #87 stone, and then compacted and leveled the infill to complete the installation.
The finished cart path wraps from the top of the house, past the retaining wall and lookout landing, and arrives at the stabilized parking landing. The family now has a safe and stabilized pathway to enjoy the entire lakefront property for years to come.