The EA identifies strategies for reducing the frequency of flooding-related closures at Wolfe Ranch and Delicate Arch Road by improving the flow of water and sediments. Major components of this project include mechanical excavation and sediment removal from Salt Valley Wash, Salt Wash, Winter Camp Wash and mechanical removal of 54 acres of invasive tamarisk.
Flooding-induced road closures of the area have increased in frequency and duration in recent years. All 15 culverts installed under the road at the three wash crossings have filled in with sediment and are non-functional.
Closing the flooded road, assisting stranded visitors, and removing sediment and debris has required more substantial efforts by park staff and, according to Park Superintendent Kate Cannon, inconvenienced scores of park visitors.
Road closures often last several days, preventing many visitors from accessing Delicate Arch, the most famous natural feature in the park.
Tamarisk is a non-native shrub that is extremely invasive in riparian communities, nearly completely replacing native vegetation with impenetrable thickets in many areas. Increased tamarisk cover at Wolfe Ranch and Delicate Arch Viewpoint areas has clogged wash channels, exacerbated problems of sediment accumulation, and interfered with the natural flow of water.
During this project, sediment removed from the wash channels will be disposed of on-site in large sediment deposit areas selected to avoid impacts to native vegetation. Park staff will monitor these sites and treat any non-native plants that may occur as a result of the wash sediment introduction. Native seed mixes will be used on the sediment deposit sites to support growth of native plant species.
Project activities would take place from November 2017 through March 2018 and from October 2018 through March 2019.
Operating heavy machinery in the delta and wash channels will have visual and sound impacts during the project. These impacts will mostly be seen and heard by visitors at the Delicate Arch parking area and along the Delicate Arch trail. No road, parking area, or trail closures will occur as a result of this project.
The EA will be available for public review and comment Oct. 17 through Nov. 16 on the NPS Planning, Environment and Public Comment (PEPC) website at:
Hard copies of the EA will be available for review at the Southeast Utah Group Headquarters on Resource Blvd., the Arches National Park Visitor Center and the Grand County Public Library.
Comments unable to be made on the PEPC website can be sent to: National Park Service, Southeast Utah Group, Attn: Planning and Compliance Coordinator, 2282 S. West Resource Blvd, Moab, Utah 84532.
Deadline for comments is Nov. 16.