Chris Soller headed across a Fire Island beach ravaged by Superstorm Sandy two years ago and stopped to admire the unexpected gift the deadly storm left behind: water clear enough to see the sandy bottom of the long-polluted bay.

The storm that killed at least 159 people and destroyed more than 650,000 homes when it slammed the U.S. East Coast also tore two breaches through the long barrier island that lies across the murky Great South Bay from New York's Long Island.

The gap that remains open is allowing the Atlantic Ocean to surge in and out of the bay, and the water near the breach is cleaner, with more plentiful fish, than it has been in decades.

Twice-daily tides over the last two years have flushed away suburban runoff from sewage and lawn fertilizer that sparks algal blooms known as Brown Tide and kills off underwater grass vital to marine life.

"It's almost like a gift from Sandy," said Soller, superintendent of Fire Island National Seashore.

"It looks positively tropical. I don't ever recall seeing the bottom before," said Charles Flagg, a professor and expert in coastal oceanography at Stony Brook University's School of Marine and Atmospheric Sciences, which is studying the Great South Bay.

The breach, located in a federally protected wilderness area, has remained open while government protocols are met for deciding whether to close it. Work crews closed the other breach soon after the Oct. 29, 2012 storm.

Clams that had all but disappeared in the bay, which in the 1970s supplied most of the U.S. market, are now growing faster near the breach than anywhere else in the bay, said Stony Brook marine biology professor Chris Gobler.

The bay's flounder, bluefish, tautog, butterfish, cancer crabs and lady crabs are now six times more plentiful than before the storm, said Stony Brook associate professors Mike Frisk and Bob Cerrato, both experts in marine populations.

SWIMMING AGAIN

The breach at Old Inlet bisects the slender 32-mile (51 km) long Fire Island, which is no more than 1,500 feet (457 meters) across at its widest point and has a population of fewer than 500 residents year-round that swells to 10,000 in summer, Soller said.

Before Sandy, swimming was no longer an option in the bay. Water clarity was just 3 feet (1 meter), short of the 4-feet (1.2 meter) minimum set by the state Health Department, Gobler said.

"It's made the bay swimmable," Gobler said. "I just can't imagine that anybody is going to move to close this thing."

But closing the breach is exactly what Suffolk County Executive Steve Bellone sought in 2013, citing concerns that it caused flooding in the months after Sandy struck.

However, the U.S. Geological Survey published a study earlier this year that found the breach had nothing to do with post-Sandy coastal flooding. It placed blame on a series of severe winter storms. In fact, Soller said, storm water is draining out of the bay faster than before Sandy.

Bellone's office declined to respond to requests for comment and whether its position had changed.

Ultimately, the decision on whether to close the inlet lies with the National Park Service, which will consult with the Army Corps and the state Department of Environmental Conservation (DEC), Soller said.

Much is riding on an environmental impact statement or EIS, which is required before repairing a breach in the wilderness area, and could take a year to complete, Soller said. Work on the EIS has not yet begun.

"Our position is that nature should take its course unless the breach is causing threats to life or property," Soller said. "There is no sign the breach is resulting in those things."

The Army Corps typically favors closing breaches on Fire Island to protect bay shore communities during severe weather, but gives special consideration to breaches within the island's wilderness area, spokesman Ken Wells said. The state DEC awaits the EIS conclusion, said spokesman Peter Constantakes.

If the breach is closed, the bay will return to its previous polluted state in a matter of months, Flagg said.

"It will undo all the good that the breach has done," Flagg said.

But Mother Nature may have the final say.

Left to its own devices, the inlet could seal up in "six months, six years, six decades," Flagg said.

"All inlets are ephemeral," Gobler said. "Over time, all inlets close."