Jul. 07, 2011

Sustainable NYC: Cleaning the Gowanus

by Jesse Medalia Strauss

Click to enlarge images

The walk through Brooklyn from Red Hook to Park Slope is generally a pleasant one. The stroll up Union Street samples the best rolls, pizza, and coffee shops New York has to offer. Not to mention the Egg Creams, a Brooklyn staple. But once you pass the Union and Bond Street intersection, whatever appetite you had immediately evaporates with the overwhelming stench of a century and a half of sewage waste and pollution. You are about to cross the bridge over one of the most contaminated waterways in the country: the Gowanus Canal.

A Bit of History:
The Gowanus Canal was constructed in 1869 out of the Gowanus Creek. It is 1.8 miles long and is filled by the Gowanus Bay which leads into the Upper Bay which leads into the Hudson and East Rivers.

Built in the height of the Industrial Revolution, the canal became a breeding ground for heavy industry. Factories sprouted all along its sides. The shipping capabilities provided by the canal turned Red Hook into a major industrial hotspot. Transportation was not the canal's only purpose. It also served as Red Hook's open sewer and a garbage dump for all the factories and industry.

The New York State Legislature never allocated sufficient funds for canal locks or a flush system. The Army Corps of Engineers figured that the tides would be enough to clean out the canal. However, they were sadly mistaken. Soon the Canal became too polluted for use, and for half a century the water remained stagnant and its toxins festered. Over the years the stench has gotten so repugnant that the locals ironically nicknamed the Gowanus "Lavender Lake."

The Current Situation:
The Gowanus Canal is arguably to most polluted water source in the United States. Its opaque surface is littered with trash. Rumors persist that the canal was a mafia body dumping ground. The concentration of oxygen is about 1.5 parts per million. It takes at least 4 parts per million to sustain life. Sunlight cannot penetrate its thick, toxic depths, making it impossible for algae and other aqua plant life to grow.

But the worst environmental offense lays within the mud that lines the bottom. This is where over fifty years of chemical and industry waste has embedded itself. The mud is ripe with lead, PCBs, toxic chemicals, and even mercury.

The Clean Up:
In March, 2010 the Environmental Protection Agency (EPA) designated the Gowanus Canal as a Superfund site. Superfund refers to the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA). Superfund sites are among the most toxic and hazardous areas in the nation. The EPA can designate sites as Superfund sites and can compel polluters to help pay for the clean up.

Gowanus Canal Clean Up Site

Cleaning up the Gowanus will take an estimated 10-12 years at a cost of $300-500 million. One of the processes required for the cleanup is called dredging, which is a means to remove the sediment or mud at the bottom of the canal. Once the mud is removed, it will either be shipped to a landfill and treated as hazardous waste, or it will undergo a process called vitrification. What this will entail is putting the mud in large metal molds that are then heated to 2000 F. This kills the toxins and turns the mud into glass which can be recycled and be used in buildings or sculptures.

The Future:
If all goes according to plan, in the next decade the Gowanus will be a place where people can boat, fish and where kids can play, maybe even swim. It will take a lot of time, money, and ingenuity -- but anything is worth getting rid of that horrible stench.

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About Jesse Medalia Strauss

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