OnEarth spoke to Mark Izeman, director of NRDC's New York urban program, which works to protect the nation's largest metropolitan area.

Why should restoring the New York City waterfront be a top environmental priority?

For starters, it's the greatest untapped area of open space in the city. The shoreline is longer than the entire coastline of Cape Cod, but historically much of it has been walled off from the public. Second, revitalizing the waterfront must also be seen as a key element in jump-starting the region's new green economy. There are huge opportunities to create and preserve environmentally friendly industries, including the city's historic maritime industry.

Can you give us some examples of how the waterfront can help build a green economy?

I can think of two good examples. The first is the city's state-of the-art recycling facility, which is being built along the Sunset Park waterfront in Brooklyn. And the second is the ongoing effort to transform the historic Brooklyn Navy Yard on the East River into a green industrial park. Both of these projects will not only help create thousands of new jobs in green industries, but they will also help reduce city air pollution by using our barges and boats-instead of relying exclusively on trucks-to move people, goods, and recyclables.

How clean are New York City's waterways these days?

Well, over the past 40 years the level of pollution has declined dramatically in the harbor. But significant problems persist, such as toxic PCBs (polychlorinated biphenyls) in the Hudson River and dioxin contamination in the Passaic River in New Jersey. And, despite sharp reductions in sewage pollution since the 1970s, our waterways are still regularly contaminated by untreated sewage discharges from our antiquated sewer system. Indeed, every time it rains, millions of gallons of raw sewage and rainwater are discharged into the surrounding rivers and bays from hundreds of outfalls dotting the coastline. This lingering problem limits New Yorkers' recreational opportunities, such as kayaking and swimming. At the same time, the city's sewage treatment plants also need to be upgraded to remove more nitrogen from our sewage wastes. High nitrogen levels lead to algae blooms that harm fish and other aquatic life. 

And what about eating fish caught off the city's coastline? Are they safe to eat?

Unfortunately, despite all the gains we have made since passage of the federal Clean Water Act in 1972, there are still significant health concerns with eating fish from the city's waterways. The biggest problem is PCB contamination, which comes from the more than one million pounds of PCBs dumped into the Hudson River by General Electric over a 30-year period. Because of this toxic legacy, New York State officials advise that any fish caught from the Upper Hudson should not be eaten. And officials warn that  most fish species from the Lower Hudson should not be eaten more than once per week .