The WCRC has established a U.S. Army Corps of Engineers (USACE) stream and wetland mitigation bank to service permittee required mitigation in the Northwest Arkansas. The WCRC developed a Prospectus for establishing the bank in September 2012 and the bank was formally recognized with a signed Banking Instrument in August 2014. The mitigation bank provides both stream and wetland mitigation credits to USACE permittee whose projects create unavoidable impacts to waters of the United States. The mitigation bank seeks to create and enhance aquatic habitat, stabilize stream banks, restore riparian areas along the river and its tributaries, and preserve and restore wetlands areas. To achieve this objective, the WCRC developed a mitigation plan that restored 1,500 feet of the WFWR using Natural Channel Design Principals and restored and preserved 15 acres of unique wetland habitat in the WFWR floodplain. All proceeds from this mitigation bank are used to subsidize finance other stream restoration projects in the Upper White River watershed and to provide a source of maintenance funds for previously constructed stream restoration projects.
The WCRC performed all activities in developing and implementing a restoration design that met the requirements of the mitigation plan found in the banking instrument. The WCRC completed a geomorphologic and topographic survey that was used to develop in construction drawings using in-house staff. In order to track success of the project in reducing sediment and nutrient inputs to the river resulting from streambank erosion, the WCRC installed toe-pins to monitoring lateral erosion and sampled bank materials for physical and chemical properties prior to implementing the restoration design. The WCRC solicited bids for construction in the winter of 2015 and the project was constructed starting in May 2015. The WCRC provided intensive construction oversight to ensure that the project would have the greatest chance of long-term success. An extensive revegetation plan using in-house expertise to create a native and diverse riparian landscape to surround and protect the restored river. Over 4,000 trees and shrubs have been planted along with native grasses and wildflowers.
In 2017 the project site entered its third growing season. After several significant flooding events, including floods that exceeded bankfull conditions by a factor of eight, the site has required minimal channel maintenance. Native vegetation planted at the site has begun to flourish and on-going vegetation management including new plantings as well as invasive species control continues to promote and ecologically diverse riparian landscape.Based on post-construction surveys, sediment and nutrient load to the river have been reduced by at least 96% throughout the restoration reach. Approximately 1,800 tons of sediment and 1,200 lb of Phosphorus are kept out of the stream annually as a result of the restoration work conducted at the site.
The WFWR mitigation bank services the Beaver Reservoir and Bull Shoals HUCs. Purchases from the WFWR Mitigation Bank are used to support expansion of ecological restoration throughout the Upper White River basin. For more information about purchasing mitigation credits from the WCRC, contact us at (479) 444-1916.