Once known as the “Gashouse District,” the area around the Gowanus Canal is the only underdeveloped section of brownstone Brooklyn, for good reason: The canal is disgusting. The EPA wants to label it a Superfund site and decontaminate it, but Mayor Bloomberg is fighting that stigma, arguing that his alternative cleanup plan will be faster and less bureaucratic. Here, the canal’s foul past and potential future.
Built in the mid-nineteenth century where a creek once meandered, the Gowanus Canal served foundries, coal yards, and paint and ink factories. In 1910, a local businessman was already describing the canal’s water as “almost solid” with sewage. The next year, a 6,200-foot underground tunnel, fitted with a seven-foot propeller, was opened to flush the canal with fresh seawater. That worked until around 1961, when the pump broke. (Local lore says a city worker dropped a manhole cover on it.) It wasn’t fixed until 1999, and will be fully overhauled by the DEP in the next two years.
Last dredged in 1975, up to twenty feet of sediment has piled up, particularly near the shorelines. The Army Corps of Engineers’ Mark Lulka says it is composed of sand, gravel, mud, and a substance he describes as “black mayonnaise.”
The oily odor comes from decades of industrial dumping and runoff, and the rotten-egg scent (much reduced since the flushing tunnel was fixed) comes from sewage. The latter spills directly into the canal after storms, when rainwater overwhelms the sewers. When that happens, the water changes from its usual dark gray to greenish because of algae feeding on the human waste.
Many of the canal’s old wooden bulkheads are breaking down. Removing and/or rebuilding them will be expensive and complicated, both because they may have soaked up a lot of toxins and because they’re privately owned.
The industrial plants that lined the canal handled just about every nasty thing that could end up in the water. Certain oily pollutants like coal tar that are customarily measured in parts per million are, in the Gowanus, measured in parts per hundred. Heavy metals like mercury and lead are present; so are PCBs and pesticides.
Cholera, typhoid, typhus, gonorrhea: They’ve all been found in the water. A team of biology professors at New York City College of Technology have also studied a curious white goo oozing along the bottom, which turned out to be a mix of bacteria, protozoans, and various contaminants. The microbes appear to have evolved resistance to the filth, and the scientists have been trying to figure out whether their disease-fighting mechanisms could be adapted for medical use.
Since the flushing system was reactivated, the water’s surprisingly lively. Oysters, white perch, herring, striped bass, crabs, jellyfish, and anchovies can be found. In 1952, a shark made its way in. (The cops shot it.) In 2007, a minke whale swam into the canal, beached itself, and died.
The Potential Cleanup
Both Bloomberg and the EPA call for most of the muck to be dredged. (They differ over who pays for it, and who administers the project.) In some areas, a foot or so of heavy clay might be laid over parts of the canal’s bottom, sealing in the bad stuff. (A similar method is used for capping garbage landfills, and has been known to hold up for several decades.) Once that’s done, there are multiple options for leisure-time access to the waterfront. One beguiling, if blue-sky, idea calls for a grassy area at the water’s edge that would function like a wetland, absorbing the rainwater that now washes sewage into the canal. It would be called Gowanus Canal Sponge Park.