Little Sugar Creek NWA @ Razorback Greenway Trail – Bella Vista, Arkansas
Before
After
After Construction – Little Sugar Creek @ Razorback Greenway Trail, Bella Vista, AR
The Watershed Conservation Resource Center (WCRC) was contacted by the NWA Trailblazers to evaluate streambank erosion conditions along a section of Razorback Greenway running adjacent to Little Sugar Creek in Bentonville Arkansas. The property is owned by the City of Bentonville. The site is located approximately 1,000 feet downstream of the Lake Bella Vista Dam and has a watershed area of 86 mi2. The NWA Trailblazers staff was concerned about ongoing streambank erosion and its impact on the trail due to the close proximity of the trail alignment with Little Sugar Creek. The streambank restoration project protects the trail from scour or loss, while at the same time helps to prevent streambank erosion and the negative effects of sedimentation. Prior to visiting the site, the WCRC evaluated the magnitude of erosion over a ten-year period (2007 to 2017) using aerial imagery and found the streambank in question had eroded as much as 24 feet, in some places. The erosion rate posed a threat to the proposed trail alignment.
Before Construction
Based on the site visit, the primary mechanism for the bank failure is erosion of the toe with subsequent cantilever failure of the upper banks. Restoration at the site involved fortifying the toe of the streambank using natural materials and creating floodplain features. The restored streambank was created with a resistive revetment of logs, brush, gravels, and boulders. Such an approach provides resistance to scour during a vegetation re-establishment period (3-5 years) after which, the area has remained stable, barring catastrophic flooding.