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Lake Montauk Harbor Feasibility Study

Lake Montauk Harbor is located on the south fork of eastern Long Island, Suffolk County, NY.  The harbor opens to the north into Block Island Sound through an inlet stabilized by two jetties.  There is an existing Federal project at Lake Montauk Harbor that provides for a channel 12 feet deep at MLW and 150 feet wide, extending about 0.7 miles from the 12 foot contour in Block Island Sound to the same depth in the yacht basin east of Star Island; a boat basin 10 feet deep, 400 feet wide, and 900 feet long, located northwest of Star Island; east and west jetties and; the addition of sport fishing facilities on top of both jetties.

A Feasibility Study was completed in partnership with the New York State Department of Environmental Conservation and the Town of East Hampton to address the concerns about inadequate channel depths for the larger commercial fishing vessels and erosion effects in the vicinity of the inlet. The feasibility study developed improvement plans to provide the most suitable solution for the study area problems.

Preliminary plans of improvement for dual purpose storm damage reduction and navigation improvement combinations were prepared for the study area, in coordination with the New York State Department of Environmental Conservation and the Town of East Hampton. No storm damage reduction plan has been able to be agreed upon with the Non-Federal sponsor, therefore the study was finalized to only consider navigation improvement plans. Upon concurrence from the Non-Federal sponsor on the selected plan (one for navigation improvement only), a Draft Feasibility Report was submitted for review and approval.  Per 2017 coordination with the New York State Department of Environmental Conservation and Town of East Hampton, the study was closed out of the Sandy Program and transitioned back as a navigation only study.

A Draft Feasibility Report and Environmental Assessment was released in July 2019 for a public review. Following the public review, a final report was prepared and is posted.  The final report recommends deepening the navigation channel to -17 ft. MLLW and creating and maintaining a deposition basin 100 ft. wide immediately east of the channel also at -17 ft. MLLW.  Material from the initial deepening will be placed on the eroded shoreline west of the inlet jettys for a distance of approximately 3,000 ft.

Lake Montauk Harbor Navigation Improvements Feasibility Study Final Feasibility Report 

Appendix A: Engineering and Design

Appendix B: Cost Engineering 

Appendix C: Economics 

Appendix D: Real Estate 

Appendix D: Navigational Servitude

Lake Montauk Harbor Navigation Improvements Feasibility Study Final Environmental Assessment

Finding of No Significant Impact: Lake Montauk Harbor Navigation Improvements Feasibility Study

Appendix A: Clean Water Act

Appendix B: Essential Fish Habitat Assessments

Appendix C: Endangered Species Act - USFWS

Appendix D: Endangered Species Act - NMFS

Appendix E: Cultural Resources 

Appendix F: CZMA Consistency Determination - with letter

Appendix F: CZMA Consistency Determination

Appendix G: CZMA Consistency Determination  

For more information please read the Fact Sheet or email the Project Manager.