Living shorelines: Recovery, restoration, and resiliency after Hurricane Sandy

The East Coast of the United States, known for its beauty as a scenic destination for residents, visitors, and wildlife alike, has emerged from the impacts of 2012’s Hurricane Sandy with a new approach to tackling protection through resiliency. Devastating weather-related events like Sandy, along with the storms and hurricanes that have followed, have put a spotlight on our shorelines for opportunities to not only rebuild but to fortify our coasts through a holistic approach to better serve as our first line of a defense.

With Hurricane Season nearly upon us (extending from June 1 to November 30 for the Atlantic), it’s a great opportunity to focus on ways we can reduce flood and storm impacts using nature-based solutions. For coastal engineers like me, it’s also an opportune time to examine how emerging resiliency tactics like living shorelines are helping protect the East Coast from future weather-related events.

My colleagues and I have collaborated with many local communities, as well as state and federal agencies, to implement uniquely selected resilient-design features in several projects along the coast. The mission: restore and reinforce our coastline using elements that will naturally complement and fortify the local environment.

Living shoreline approaches often include a hybrid of environmental and man-made features, including a variety of structural and natural materials such as wetland plants, submerged aquatic vegetation, shellfish reefs, coir fiber logs, sand fill, and stone. For example, an “ideal” living shoreline in many tidal areas contains a succession of natural features that would normally be found in undisturbed ecosystems.

Of course, these elements vary greatly based on the location and ecology of a specific shoreline. Even along the coast of the Mid-Atlantic and Northeast, we have utilized varying tactics when working with living shorelines for reinforcement.

Strengthening Staten Island

The south shore of Staten Island has a long history of coastal erosion and was one of the hardest hit areas in the metro New York City when Hurricane Sandy came ashore.  

As part of its New York Rising Plan, the state launched a series of storm recovery and resilience initiatives. One of these, the Tottenville Living Shoreline Protection Project calls for the design and construction of a multi-tiered living shoreline system to reduce wave impacts and coastal erosion along this residential and commercial neighborhood.

Led by our NYC Landscape Architecture studio, the team is truly interdisciplinary, bringing together landscape architects, coastal engineers, ecologists, structural engineers, and stormwater engineers. The team is working in concert with the community to design a shoreline plan that builds resiliency against major storms. It includes:

• Wetland enhancement
• Eco-revetments
• Hardened dune systems
• Shoreline plantings
• Maritime forest restorations
• Earthen berms

It’s important to note that these tactics are designed as a risk-reduction strategy. This approach aims to reduce the impacts of coastal flooding and shoreline erosion, restore and enhance ecosystems, and increase social resilience by improving waterfront access.

Protecting Prime Hook

Further south, the restoration of the Prime Hook National Wildlife Refuge along Delaware Bay, one of the largest tidal marsh restoration projects in the eastern United States, has been recently completed.

Here, Hurricane Sandy opened a new breach in the barrier island and wreaked havoc on the 10,000-acre tidal marsh/barrier beach ecosystem. The storm destroyed this sensitive habitat for migratory birds, fish, and other wildlife, further degrading this already battered wetlands area.

By engineering in a way that complements—rather than opposes—nature, our team focused on reestablishing a critical habitat in a way that will support the ongoing rejuvenation of the wetlands ecosystem.

Our work on this project includes placing approximately 1.1 million cubic yards of sand from an offshore borrow area along the shoreline. We reconstructed a 40-foot-wide dune, 150-foot beach berm, and back-bay marsh platform.

The marsh restoration portion of the project included dredging 30 miles of conveyance channels and “thin layer” disposal of 600,000 cubic yards of sediment to help manage and restore the flow of tidal currents. Through our work in the refuge, managed by the U.S. Fish and Wildlife Service, we have helped establish ecosystems to give the habitat strength to endure, adapt, and thrive in the face of future storms.