A little more than a year ago, we filed this report about what would happen if Hurricane Irene were to cause flooding in the Gowanus Canal. The canal avoided flooding by a few scant inches, but as Hurricane Sandy bears down on New York, a storm surge is looking even more likely, so we've updated our post from last year.
As Hurricane Sandy begins to arrive in the New York area on Sunday, the neighborhoods surrounding the Gowanus Canal are in for a literal shitstorm — and that may be the least of their problems.
The latest projections anticipate a storm surge of several feet in New York Harbor on Sunday. A dome of water would travel from Upper New York Bay, through Gowanus Harbor, and into the 1.5-mile-long Gowanus Canal near Smith and 9th Street. Once in the canal, it could stir up a heady mix of pollutants — essentially oil, heavy metals, and human excrement — and distribute it throughout the slowly gentrifying area that sits among some of Brownstone Brooklyn's priciest neighborhoods. In Gowanus itself, a host of new restaurants and bars have recently opened, a developer is trying to revive plans for luxury housing along the canal banks, and a new Whole Foods is set to open next year.
Update: As of 9:30 pm on Sunday night, photos posted on Twitter show the Gowanus has already begun to overflow on 2nd St., with water pushing up about 15 feet before the wind and rain and storm surge have even arrived in earnest.
Ask any Gowanus resident, or any of the artists and restauranteurs who have recently staked out space there, and they'll tell you that it's no fun for anyone with a functioning olfactory system to be near the canal when it rains. That's because the city's sewer system overflows into the canal whenever it maxes out its capacity to handle runoff, which happens all too often, resulting in a disgusting wave of human poop. The canal can be even fouler at low tide on a sunny day, when water levels drop low enough to expose the polluted sludge — mostly 100-year-old oil and coal byproducts, and PCBs from metal and paint factories — that lines its banks.
If Sandy hits with sufficient force, a flood of the human waste quaintly known as combined sewer overflow (CSO) is almost a certainty. What is less certain is how much of the heavier, more dangerous contaminants will be churned up by the storm surge and heavy winds and deposited by the flood waters. There is a worrying precedent in Hurricane Katrina, which inundated several Superfund sites such as the Agriculture Street Landfill. Like the Gowanus Canal, the landfill had accumulated decades worth of various pollutants, and after Katrina the area around the landfill showed "disturbingly high" levels of cancer-causing chemicals from soot and petroleum-based products. Those are known as polyaromatic hydrocarbons (PAHs), and EPA testing has confirmed high levels of them in the Gowanus Canal, the result of oil and coal refinery runoff a hundred years ago.
The 50-odd blocks that surround the canal — known lately for open-air dance parties and hipster houseboats — are in Zone A and are subject to mandatory evacuation. The two neighborhoods that border the Gowanus, Park Slope and Carroll Gardens, are both uphill from the canal. But whether those hills are steep enough to turn back a flood of toxic poop won't be known until Sandy passes through.