Nassau County Back Bays Study

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Nassau County Back Bays Coastal Storm Risk Management Study

Status Report and Public Meetings

The U.S. Army Corps of Engineers and its partners, the New York State Department of Environmental Conservation and Nassau County, hosted public meetings regarding the Nassau County Back Bays Coastal Storm Risk Management study on June 12 in the Village of Freeport, NY and on June 27 in the City of Long Beach, NY. Video recordings of the meetings are posted below.

The U.S. Army Corps of Engineers released a status report on April 30, 2019, which includes information on work completed to date, potential alternatives under consideration, an overview on the study process, and details on next steps.

Nassau County Back Bays Coastal Storm Risk Management Study Status Report (April 2019)

Potential Measures Under Consideration

Storm Surge Barriers

Storm surge barriers consist of a series of movable gates that stay open under normal conditions to let navigation and flow pass but are closed when storm surges are predicted to exceed a specific water level. This is one of several measures under consideration as part of the study.

Non-structural Measures

Non-structural management measures are intended to reduce consequences flooding has on assets exposed to flood risk, as opposed to a structural measures that alter the characteristics or the probability of occurrence of flood risk. Elevating a structure is an example of a non-structural measure.

Natural and Nature-Based Features

Natural and nature-based features such as living shorelines are potential solutions under consideration as part of the study. Natural coastal features take a variety of forms, including reefs, barrier islands, dunes, beaches, wetlands, and maritime forests.

Floodwalls

Floodwalls are a measure under consideration as part of the study. Floodwalls are vertical structures constructed with steel or concrete that are used to reduce risk of flooding. Floodwalls are most commonly used where there is limited space for large flood protection measures.

Bulkheads

Bulkheads are vertical structures with the primary purpose of retaining land that adjoins a water body. Bulkheads, unlike floodwalls and levees, are generally constructed at or near the existing grade and flood risk management is of secondary importance.

Study Area Map

Study Background

Background

The south shore of Nassau County is at increasing risk of natural hazards such as coastal erosion, coastal wave action, storm surge, flooding, and severe winds caused by coastal storms. This is largely due to the area’s geography, topography, and land use patterns. Many of the tidally influenced areas of Nassau County are at a low elevation, densely developed with residential and commercial infrastructure, and subject to flooding during high tides and storms.

These problems were highlighted by Hurricane Sandy, which made landfall in October 2012 and severely impacted the area. Over 1.3 million Nassau residents were affected by the storm. In response to the destruction caused by the storm, the U.S. Army Corps of Engineers (USACE) completed the North Atlantic Coast Comprehensive Study (NACCS). The NACCS January 2015 final report identified areas along the Atlantic Coast at high risk of coastal storm damage. The portion of southern Nassau County influenced by back bay flooding was identified as one of these high risk areas. USACE, New York State Department of Environmental Conservation (NYSDEC), and Nassau County have partnered to investigate ways to reduce coastal storm risk in this area. This includes communities in the Town of Hempstead and Town of Oyster Bay located within southern Nassau County, as well as the City of Long Beach, that front Hewlett Bay, Middle Bay, Jones Bay, South Oyster Bay, and connected creeks, channels, and minor waterbodies (the "Nassau County Back Bays").

The purpose of the Nassau County Back Bays feasibility study is to investigate potential ways to reduce the risk to people, critical infrastructure, and businesses caused by coastal storms such as Hurricane Sandy. The study team is investigating potential solutions that could reduce flood risk in ways that support the long‐term resilience and sustainability of communities and the environment, and that reduce the economic costs and risks associated with coastal storm damage. The team will look into the feasibility of a number of measures, which includes but is not limited to storm surge barriers, bulkheads, floodwalls, levees, seawalls, shoreline stabilization, stormwater improvements, beach nourishment, living shorelines, wetland restoration, and the elevation, floodproofing, and/or relocation of structures.