Ocean/Bay Exchange in the Great South Bay

The Fire Island breach created by Superstorm Sandy in 2012 demonstrated the positive influence that greater ocean exchange can have on estuarine waters. The “Wilderness Breach,” as it came to be known, delivered clean ocean water to a stagnated and polluted section of Great South Bay, resulting in a cascade of ecological benefits. Water clarity improved, nitrogen levels were reduced, fish and birds returned and even wild set mollusks took hold. 

These benefits started Seatuck on an exploration of the extent to which the Great South Bay was suffering from overall poor circulation and what could be done to improve conditions. To try to answer what proved to be difficult questions we worked with a consultant to develop a new hydrodynamic model of the Great South Bay. We used the model to test a variety of hypothesis and scenarios for greater exchange. Included was the published idea that a “realigned” Fire Island Inlet could deliver water quality benefits to the heart of the bay. The modeling results indicated that while significant water quality improvements from engineered solutions at Fire Island Inlet would be difficult to achieve, there was great potential for future barrier island breaches to improve water quality if allowed to remain open for at least a period of time.

Click here for more details about the state of the Wilderness Breach.