Assateague Island National Seashore (AINS) Parking Lot Relocation
National Park Service (NPS) managers at Assateague Island National Seashore (AINS) have developed a plan to adapt roadways and parking areas to excessive erosion and overwashing from storm surges. This plan is in progress, and this case study will be updated accordingly. Two parking lots will be relocated away from the shoreline to reduce their vulnerability to erosion from future storms and help restore natural coastal processes. Additionally, they will be reconstructed from materials that are readily available on Assateague Island, such as clay and crushed clam shell, which will help reduce water flow rates over the parking lots and corresponding risk of erosion.
Assateague Island is an uninhabited, 39,727 acre national park located on a 37-mile long barrier island off the Atlantic coasts of Virginia and Maryland. One major roadway connects a series of parking lots that are essential to recreational enjoyment of its beaches and wetlands. The NPS expects that as sea levels rise and storm surges become more frequent, shoreline retreat and wave overwash will increase the already considerable cost of maintaining fixed assets such as paved roads and parking lots. Officials expect that under most sea-level rise projections, the NPS will have difficulty preserving recreational access to the public. Two parking lots, the Bayside and South Ocean Beach lots, fall within FEMA’s 100-year floodplain. In 2012, Hurricane Sandy caused extensive damage to the Bayside Picnic Parking area, destroying much of its boardwalk and flooding the asphalt lot. The storm covered much of the South Ocean Beach Parking Area with sand, and also damaged pavement, curbs, and parking islands.
In response, the NPS plans to relocate both parking areas, and reconstruct them with a clay base and crushed clamshell surface. The removal of asphalt from both parking lots and construction with natural materials will be beneficial for restoring and maintaining natural processes. The rough clam shell surfacing of the parking lots will convey water from precipitation events much more slowly than traditional paved surfaces, allowing surrounding wetlands to better absorb these flows and reducing sedimentation and erosion risks. The relocation of the parking areas will also benefit coastal processes and flood control. By removing or phasing out the existing parking areas, the shoreline can return to a more natural state of sediment transport, and the larger natural buffer area between the shoreline and inland parking areas will better allow the wetlands to support floodplain functions and shoreline stabilization. In these new positions, the parking lots would therefore be more resilient and less vulnerable to the effects of erosion and flooding, while continuing to allow public access to the beach.
The plans for these picnic and parking areas have been detailed in two separate environmental review processes. The NPS selected the removal and relocation alternative for the South Ocean Beach Parking Area from two alternative plans (no action, or removal and relocation), which were detailed in an initial environmental assessment (EA) submitted for public comment in August 2013. The NPS decided to reconstruct the Bayside Picnic and Parking Area from clay and clamshell at that time as well, but has more recently continued to evaluate location alternatives. In a new EA released in September 2015, the NPS evaluated five alternatives for the Bayside Picnic and Parking Area: the “no action” alternative (which would have maintained its location but still reconstructed the parking area with clay and clamshell), and four “action” alternatives each with a different plan for modifying the location and size of the picnic and parking areas. The NPS announced its preferred alternative, Alternative 4, which will move the parking area inland by removing the existing Bayside Campground Loop C and constructing a new parking area in its place. Most of the existing parking area would be phased out and allowed to revert to natural conditions. Public comment was open on this EA through November 2015.
Separately, the National Park Service is developing a new General Management Plan (GMP), which will govern management at AINS for the next two decades. The GMP assumes that all assets on Assateague will have to weather more intense storms, greater erosion, inlet breaching, and shoreline retreat. The GMP will codify successful practices, such as the past introduction of mobile facilities, including moveable storm shelters and latrines. The managing authority for Assateague already limits construction materials for roads and parking lots to local clay and clam shells, which permit more efficient relocation of transportation assets. The NPS released a Draft General Management Plan / Environmental Impact Statement (“Draft GMP”) for AINS in January 2016, which will be open for public comment until May 1, 2016. Of four alternatives considered for the GMP, the NPS’s preferred alternative is Alternative 3: Sustainable Recreation and Climate Change Adaptation. This alternative places climate change adaptation at the forefront in management of the park, emphasizing the importance of natural processes and the need to evolve visitor use and infrastructure design and locations over time. Under this alternative, manipulations of the natural environment would be kept to the minimum feasible in order to sustain recreation opportunities. It would also provide for alternative transportation options for accessing the island, particularly ferry systems, to be phased in over time (with a full shift-to water-based transportation in the event of losing vehicular access due to coastal processes and the effects of climate change and sea-level rise).
AINS falls under the jurisdiction of three federal agencies: the National Park Service, the U.S. Fish & Wildlife Service, and the Department of Natural Resources. Through a 1967 agreement with the USFWS, ASIS (the NPS body responsible for managing AINS) assumed responsibility to preserve the recreational beach on Assateague Island, including access routes and parking lots.
This Adaptation Clearinghouse entry was prepared with support from the Federal Highway Administration. This entry was last updated on January 29, 2016.
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