The Big (Green) Apple

As flat as a pool table and barely a mile wide at its narrowest, the Rockaway Peninsula--a tongue of land that sticks into the Atlantic Ocean at New York City's southeastern corner--is already vulnerable to storm surges and floods. Global warming, with its rising seas and harder rain, will only intensify those threats. That's what has Vincent Sapienza, the city's assistant commissioner for wastewater treatment, so worried. The Rockaway Wastewater Treatment Plant, which processes 25 million gal. (95,000 cu m) of sewage a day, sits next to the beach, and its pumps are below sea level. In a major flood, parts of the plant could be submerged, shutting down sewage treatment. "If you lose these pumps, you're done," says Sapienza, standing in the plant's churning basement. "This is a really vulnerable place."

To prepare for climate change--and growth--the city is spending $30 million to raise the pumps and other electrical equipment at the Rockaway plant well above sea level. The overhaul is just one part of New York's groundbreaking PlaNYC--a long-term blueprint to grow the U.S.'s biggest city green in the age of global warming. "This is about making the city more sustainable," says Sapienza.

Though it's caricatured as a concrete jungle, New York is already surprisingly eco-friendly. Thanks to its density and public transit, the city has a per capita carbon footprint 71% smaller than the U.S. as a whole. With more than 8.2 million people calling New York home, surpassing a historical high set in the 1950s, the city's infrastructure--its crowded subways, traffic-choked streets, aging water mains--is being pushed past its limits. City planners realize that New York is on track to gain an additional 900,000 people by 2030. If that growth isn't managed properly, the result will be an environmental and economic mess. "New York is growing, and we have to think more effectively," says Rohit Agarwalla, director of the city's Office of Long-Term Planning and Sustainability. "We can't just build more power plants. We can't just grow on the edges."

The answer to the question of where the city will put nearly a million extra people is PlaNYC. Unveiled by Mayor Michael Bloomberg on Earth Day 2007--and pushed since then with all his considerable political capital--PlaNYC includes more than 120 green initiatives that range from planting a million trees to cleaning up every square mile of contaminated land in the city.

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