No one can say when the Fire Island breach opened by superstorm Sandy will close — as most such inlets eventually do on their own — but it will be filled in only if it causes harm, under a final approved plan.
The National Park Service, in a statement Thursday, said it would only reconnect the barrier island "to prevent loss of life, flooding, and other severe economic and physical damage to the Great South Bay and surrounding areas."
“We’re committed to continuing to monitor the breach for any impacts it might have,” said Kaetlyn Jackson, a park planner for the National Park Service, which owns the Fire Island National Seashore.
The breach connects the bay and the Atlantic in the Otis Pike High Dune Wilderness, which lies east of the barrier island's communities.
The management cleared its last hurdle on Monday when Northeast Regional Director Gay Vietzke signed a Record of Decision, the National Park Service said.
Its shape, depth, width, water quality and effects on the surrounding area, notably Bellport that lies just north, have been studied by scientists and the National Park Service since Sandy created the breach in 2012.
Fears that the breach increased flooding were not borne out, scientists said. Research showed salinity rose and tide levels were fairly stable, though they arrived about half an hour earlier in Bellport Bay. The water around the breach is a few degrees cooler in summer and a few degrees warmer in winter.
"We have seen positive impacts in the localized area, especially in Bellport Bay, with the flushing of the water; we see better water quality, a higher abundance of species and species richness," Jackson said.
Eel grass is flourishing by the breach, drawing small prey such as shrimp, which in turn have attracted flounder and other fish, Jackson said. Fishermen have taken notice.
The National Park Service said it would keep collecting data on water levels, the breach's cross-section and track how it changed so that it could act if needed. "Should such shifts occur, the NPS would increase monitoring efforts to inform a decision about whether or not to mechanically close the breach," it said.