Date: May 22, 2017
The National Park Service (NPS) is preparing an Environmental Assessment (EA) for shoreline stabilization at the South Manitou Island Lighthouse complex within Sleeping Bear Dunes National Lakeshore in accordance with the National Environmental Policy Act.
The purpose of this action is to protect the lighthouse complex through shoreline stabilization, to restore and/or improve access to the lighthouse complex, and to prevent shoreline retreat and loss of additional shoreline along approximately 800 linear feet of nearshore Lake Michigan waters. The NPS is seeking public comment about potential issues and impacts related to this project.
The lighthouse complex is located on the southeastern shoreline of the island. The previously installed shoreline stabilization materials have been removed by wave and/or ice action or are in poor condition, with many of the foundational elements exposed and subject to additional damage/removal. Action is needed to protect the historic structures. In addition to the compromised stabilization features, wave action over the winter of 2015-2016 resulted in significant shoreline erosion east of the stabilization structures. This shoreline erosion extends east approximately 300 feet and inland 60-80. Approximately 200 linear feet of preexisting boardwalk, which provided access to the lighthouse complex, was washed away. The new shoreline in the eroded area consists of predominately sand banks that are unstable and subject to further erosion. Shoreline stabilization failure and erosion to the east are a serious concern to the nationally significant lighthouse complex, which is a Historic Landmark District. The existing shoreline is approximately 45 feet from the base of the lighthouse and 20 feet from the fog signal building.
Actions for shoreline stabilization would include rehabilitation of the existing shoreline revetment with some modifications to adjust for the recent shoreline changes. This would involve the reuse of existing stone materials as bedding and core materials, installation of geotextile, and new, properly sized and placed armor stone. To the northeast of the existing bin wall, new shoreline protection measures and footprint may take place in response to the shoreline erosion that has occurred since 2015. A combination of stone structures and imported sand would be employed to restore a sandy shoreline where it has existed historically.
Under a separate but related project, rehabilitation of the lighthouse complex would include restoration and repair of four of the six buildings in the complex: the lighthouse, the keeper’s dwelling, the passageway connecting the lighthouse and keeper’s dwelling, and the fog signal building. Restoration of the cultural landscape would include removal of encroaching vegetation, planting of native dune vegetation, and repair or restoration of small-scale features. Once the eroded shoreline and associated boardwalk access route have been reestablished, future planning may also include construction of a universally accessible route to the fog whistle building.
NPS encourages you to become involved with the process and add your voice to the planning for the project. You can submit your comments and find more information about the project at the park’s Planning, Environment and Public Comment website at https://parkplanning.nps.gov/SLBE. Please provide comments and ideas by June 5, 2017, in order for them to be considered during this preliminary phase of the project.
