Hardened shorelines cause a loss of intertidal and marsh habitats, impacting: 

• Critical habitats for horseshoe crabs, diamondback terrapins, migratory shorebirds, juvenile fish, and other wildlife
• Decline in ecosystem productivity
• Loss of ecosystem services such as atmospheric carbon sequestration

Hardened shorelines reduce coastal resiliency. 

A reduced ability of shorelines to buffer wave energy, mitigate flooding, and for salt marsh habitats to grow vertically and inland in response to rising sea levels reduces long-term resiliency

More hardened shorelines being implemented increases the loss of riparian rights.

As intertidal shoreline areas decrease with rising sea levels, the community also loses access to public beaches. 

Project Details

In 2019, PEP completed a GIS-based inventory to document the extent of hardened shoreline coverage along the Peconic Estuary. 

PEP worked with partners to ground truth the shoreline assessment. 

Goals of this inventory:

1. Assess the extent of bulkheads, revetments, piers, groins, jetties, and docks using the 2016 Orthoimagery from the NYS GIS Clearinghouse.
2. Create a tool for local governments to information decision-making regarding land preservation.
3. Form the basis of the PEP Shoreline Hardening Strategy and future projects. 

Ground-truthing efforts confirmed the accuracy of aerial interpretation of these shoreline structures. 

Results of Hardened Shoreline Validation Project

The results of this hardened shoreline validation project, in combination with the Horseshoe Crab Workgroup and eventual Horseshoe Crab Management Strategy, will aid PEP in the development of a Shoreline Management Model (SMM) to better support and inform decision-making for the agencies and municipalities that manage the shoreline resources.

The SMM is a novel, geospatial technique used to model existing and potential future conditions along a shoreline and to recommend best management practices for shoreline protection by considering a variety of factors. Such factors include wave energy, sediment type and movement patterns, submerged aquatic vegetation, value of the shoreline as wildlife habitat, risk of climate-change related impacts such as flooding, storm surge, and sea level rise. By weighing these factors, managers are better equipped to recommend the most appropriate shoreline protection strategy for a specific area. Ideal strategies minimize impact to ecosystems and aid in identification of areas where nature-based solutions may be more suitable than conventional hardened shoreline structures to maintain the ecological and structural integrity of the shoreline, as well as riparian rights for the surrounding community.

Additionally, the development of a Horseshoe Crab Management Strategy will enhance this model by allowing PEP and shoreline resource managers to incorporate information on preferred nesting habitats for this important species. This will better protect these ecologically active shorelines from development and to ensure that essential intertidal and salt marsh habitat is prioritized for preservation.