But that’s not completely true. Mr. Riepe, who nowadays is best known for the bird walks and shoreline cleanups that he leads, fully expects that in 25 or 30 years, sea level rise will make his home and many others like it unlivable. He is 82, and he doesn’t expect to be around then. But for the sake of those who will be, he and his neighbors are banking on a plan to restore the wetlands and to build up the islands in the bay, which they hope will soften the blow of future storms. It will also return some of the natural beauty for which the bay was once known.
Jamaica Bay is an estuary nearly the size of Manhattan that carves into the boroughs of Brooklyn and Queens, and it is far and away the largest natural space within New York City. For Native American tribes like the Lenape, the bay was a “hugely important hunting and fishing grounds,” according to Eric W. Sanderson, who is best known for the Mannahatta Project, which reconstructed Manhattan’s ecological past. He is now conducting a similar survey of the other boroughs.
Mr. Sanderson and a group of city officials recently paid an inspection visit to a restored marsh on the Rockaway Peninsula, an area that used to be filled with rubble, concrete blocks and construction debris. Almost as if on cue, a great blue heron glided past the group noiselessly, creating barely a ripple in the mirror-like waters. A small fenced-in plot on the shore bristled with the stalks of newly seeded marsh grasses planted by the New York City Parks Department.
Mr. Sanderson, who is a senior conservation ecologist at the Wildlife Conservation Society, gestured toward a tidal channel, above which loomed a four-story apartment complex with a “now leasing” sign.
“If we were here with the Lenape a few hundred years ago, they would be there in the channel in their dugout canoes,” he said. “But they would never have built their wigwam right there on the edge of the beach, because it’s dangerous. It floods, it’s exposed to the winds.”
The restoration area and the channel that abuts it sit incongruously between a busy avenue and a neighborhood of mostly new low-rise apartment buildings and multistory homes, many of which flooded during Sandy. The odd architectural mix and wild natural features make Rockaway unique. They also present unique challenges to city planners.
The city today has lost most of its protective sand dunes and close to 80 percent of the coastal marshlands that it had historically. Without these natural barriers, residents in the Jamaica Bay area are far more vulnerable to rising waters.