Coney Island Yard Complex Flood Mitigation (Brooklyn, NY)
The storm surge from Superstorm Sandy in October 2012 resulted in extensive flooding at MTA New York City Transit’s (NYC Transit) largest rail yard, the Coney Island Yard Complex. It sits atop a former marshland adjacent to Coney Island Creek and is located in a special flood hazard area. Flooding caused debilitating damage to track infrastructure and the maintenance shop buildings, as well as a 50% loss in the train storage capacity. STV was selected by NYC Transit to design permanent protection measures for the yard, including a perimeter floodwall and major upgrading of stormwater systems. The initial study consisted of a site investigation to identify key issues, as well as an analysis and a comparative evaluation of various flood mitigation alternatives based on cost, constructability, maintenance requirements, and schedule to implement. The final design selected was the complete replacement of one bridge with a new flood-proof structure and a major retrofit of the other bridge to also make it flood-proof. The design will comprise a two-and-a-half mile long flood wall, eight flood gates, more than 900,000 gallons of underground storage and two pump stations.