The best defense (against a storm) is a natural defense

Tottenville Shoreline Protection

The south shore of Staten Island has sustained decades of coastal erosion. Its condition, made worse by Superstorm Sandy, has left this community more vulnerable to the next coastal storm.

As part of its New York Rising Community Reconstruction Plans, the State of New York set up the Tottenville Shoreline Protection Project (TSPP), a storm recovery and resilience initiative. The design uses a layered approach comprised of a series of measures—wetland enhancement, eco-revetments, hardened dune systems, shoreline plantings, maritime forest restoration, and earthen berms. This system would serve as a naturalised barrier to the looming threat of storm damage due to wave action and shoreline erosion while enhancing ecosystems. 

Our team signed on to help. A 1D cross-shore (CHSORE) model was used to support the design of the dune system to ensure it meets the life expectance of the project. As the project progressed, we determined that the dune solution wouldn’t work for the whole shoreline. The answer? Custom design solutions for each of the diverse areas.

To inform the structural design and evaluate the risk reduction benefits of the TSPP, we developed a 1D wave transformation, a CSHORE erosion model, a 1D overland wave height analysis for flood insurance studies (WHAFIS) model, and a 2D phase-resolving wave model. These services demonstrated that the TSPP achieves the risk reduction goal to prevent waves with a height greater than 1.5 feet (45 centimetres) from reaching the property lines.