Most urban waterways have seen their share of abuse. Having acted as lifelines of industry and commerce long before anyone ever paused to consider environmental consequences, these rivers, streams, and canals have absorbed decades worth of industrial waste, chemical runoff, and untreated sewage, most of which was eventually carried into the ocean, thereby accounting for the mercury content of much of the fish we eat today.

But what if that waste hadn't been carried away? What if, instead of being swept out to sea, all those chemicals and byproducts remained right where they were dumped, festering for decades in the middle of a busy city?

These are the circumstances of the Gowanus Canal, a 1.8-mile-long waterway that connects southwest Brooklyn to the New York Harbor. In a way, the Gowanus Canal is like a time capsule of the country's industrial past; whereas as other urban waterways have improved significantly since the 1972 passage of the Clean Water Act, stagnant conditions in the canal have ensured that the majority of hazardous waste dumped decades ago -- including substances that have since been banned -- remains there to this day.

Today the canal is widely regarded as one of the country's most contaminated waterways. In March of 2010 the Gowanus Canal was declared a Superfund site and placed on the Environmental Protection Agency's National Priorities List -- meaning that the canal, which runs through the heart of some of Brooklyn's trendiest neighborhoods, was so polluted that the federal government had to step in to oversee its cleanup  (Brooklyn's other Superfund site, Newtown Creek, in addition to suffering from many of the same issues facing the Gowanus, remains a cleanup site for a century-old oil spill).

The story of the Gowanus Canal is one of industry, mismanagement, and neglect resulting in conditions that are almost unbelievable. But with recovery efforts beginning to take shape, activists in the community are working to change the narrative to one of collaboration, stewardship, and responsibility.

The Gowanus Canal: A History

Completed in 1869, the Gowanus Canal was dredged from the area's natural tidal marshes to accommodate the shipping needs of an increasingly industrial borough. By 1917 its strategic location near Manhattan, Brooklyn, and the Atlantic Ocean had earned the canal the distinction of the busiest canal in the country. Chemical plants, gas manufacturers, oil refineries, factories, and numerous other beacons of industry lined the shore of the Gowanus and used the canal as a dumping ground for industrial waste. The canal was also the final destination for raw sewage from neighboring residences and businesses. It wasn't until 1987 that a sewage treatment system was put in place, and even that was too little too late; the Red Hook Wastewater Treatment Plant has proved insufficient to handle the high volume of water amassed when storm runoff joins the residential wastewater, and routine rain showers often result in raw sewage overflowing once more into the canal.

The stench that haunts the canal today was observed as early as the 1880s, less than two decades after the canal's construction. Stagnation in the canal was rightly identified as the main culprit, and a tunnel was constructed to address the problem which natural tides had failed to remedy. The Gowanus Canal Flushing Tunnel was christened in 1911, and it was amid much fanfare that Mayor William Jay Gaynor first threw the switch that began pumping the rank canal waters into the nearby Buttermilk Channel.

From the onset, the flushing tunnel was plagued with problems and after numerous repairs it was eventually abandoned in 1961 for the next three and a half decades. When the tunnel was finally reactivated in 1999, the flow of water was reversed from the original design, this time pumping cleaner water into the canal in an effort to restore depleted oxygen levels. In 2010 the tunnel was once more taken out of service while city officials began a complete overhaul of the tunnel's machinery. A press release from the New York Department of Environmental Protection in December of 2013 announced the activation of one of the tunnel's new turbines; two additional turbines are expected to be activated this year.

The Current State of Affairs

The result of over 150 years' worth of unchecked dumping is literally unimaginable -- that is, researchers still don't have a comprehensive idea of what the canal contains or what long-term effects its contamination might have on the health of anyone routinely exposed to the water, sediment, or air in the canal's immediate vicinity. According to the EPA's Gowanus Canal Remedial Investigation Report, contaminants found in the sediment and water of the Gowanus include numerous heavy metals such as arsenic, mercury, and lead; known carcinogens such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs); volatile organic contaminants (VOCs) such as ingredients found in paint and cleaning supplies; something the EPA calls non-aqueous-phase-liquid (NAPL), also known as liquid coal tar, discharged from long-closed manufactured gas plants; and an unspeakably high concentration of fecal matter.

Of course, the presence of these materials doesn't tell the whole story; to understand the extent of pollution in the canal and the dangers it presents, one needs to determine the levels at which these contaminants are present. As it turns out, measuring those levels is no simple task. Stagnation in the Gowanus has resulted in a layering of contaminants that makes it next to impossible to measure them definitively. Dan Nosowitz, in his comprehensive article for Popular Science, sums up the situation best, calling the canal “one of the most creatively and massively pathogenetic waterways on the planet.” States Nosowitz,

“[T]he Gowanus isn't any one thing; water taken from different parts of the canal, from different depths, will have totally different levels of contaminants, microbes, radioactive materials, or carcinogenic materials [….] This is what happens when you have a huge, 1.8-mile waterway that's completely stagnant: you get micro-environments, because there's hardly any interaction between the [surface water] and, say, water a few inches above the muck in the center of the canal.”

So definitively measuring concentrations of these contaminants in the canal is difficult. But while the EPA's findings might not be applicable to every square inch of the canal, they're certainly disturbing enough to merit attention. Lead, for example, was detected in surface sediment in concentrations roughly 11 times higher than what the EPA has deemed safe. Dig down into the soft sediment below, and those concentrations go up to about 16.5 times the acceptable levels. This seems to be the case for most contaminants found in the Gowanus (79 identified in all); they're present in the surface sediment at levels already well above what's considered safe, and those numbers continue to climb the deeper one digs. Meanwhile, dissolved oxygen levels in the water hover around 1.5 parts per million, less than half of what's needed to sustain healthy aquatic life.

Speculating about pollutants in the canal deals with a known unknown. But as it turns out, the Gowanus harbors its share of unknown unknowns as well -- meaning some of the organisms that call the Gowanus home have evolved in ways we've never seen before. In 2008 the New York City College of Technology released findings made by biology professors Nasreen and Niloufar Haque who spent two years studying water samples collected from around the world. Some of the most interesting results were uncovered in the Gowanus Canal, mere miles from the City Tech campus. While diving for samples in the canal, Nasreen discovered large white clouds of biofilm floating above the sediment at the bottom. City Tech's website describes the substance as “a composite of bacteria, protozoans, chemicals and other debris.” After studying the biofilm, Nasreen concluded, “[M]icroorganisms are surviving by adapting to the harsh environment there that shouldn’t survive at all. Working in synergy, they seem to sense if nutrients are available; they exchange genes and secrete substances[.]” It's unnerving to think that conditions in the canal have forced the hand of evolution, but there is a silver lining; Haque's research found that the biofilm secretes substances that behave similarly to antibiotics and could potentially be used to develop new bacteria-resistant drugs.

Though industry along the canal has ebbed and flowed over the decades -- according to the Gowanus Dredgers Canoe Club, by the late 1970s over 50 percent of property in Gowanus was vacant or in disrepair following the decline of New York's industrial sector -- today the neighborhood has transformed into a bohemian mecca, home to art studios, restaurants, shops, and performance spaces. Most of the heavy industry responsible for polluting the canal has long since moved elsewhere or closed down altogether, but its banks remain home to a handful of scrap metal yards and cement plants, some of which continue to receive citations for failing to comply with environmental regulations.

The Gowanus Canal received Superfund designation in 2010, despite opposition from NYC Mayor Michael Bloomberg who feared the listing would discourage further development in the growing Brooklyn neighborhood. The EPA's finalized plans for the cleanup involve dredging the entire length of the canal to ultimately remove a total of 587,000 cubic yards of contaminated sediment, sealing the bottom with cement and other stabilizing materials to prevent further contamination from the sediment below (in some places the contamination goes as deep as 100 feet below ground), and then layering clean materials on top to further guard against a reemergence of that NAPL (liquid coal tar), which has a nasty habit of bubbling up to the surface. The EPA will also require New York City to upgrade its sewer system to significantly reduce sewage overflow from the combined sewer system. As-yet undefined measures will be taken to deal with nearby contaminated sites -- including the sites of three defunct manufactured gas plants -- known as brownfields.

The cleanup, currently still in its design phase, is expected to begin in 2016 and cost $506 million. According to the EPA's September 2013 release, “The Superfund program operates on the principle that those legally responsible for the pollution should perform or pay for investigations and cleanups, rather than passing the costs to taxpayers.” As of January 2013, the EPA had issued notices to 37 potentially responsible parties (PRPs), including five federal and municipal entities, and sought information from an additional 73 companies.

From Pollution to Possibilities

Not surprisingly, press about the Gowanus Canal is overwhelmingly negative. Nosowitz refers to the canal as “an absurdly, laughably polluted waterway right smack in the middle of gentrified Brooklyn,” going on to describe the situation thusly:

“The Gowanus's mere existence, in the middle of one of the richest parts of the fastest-growing borough of America's biggest city, is one of those casual New York City things that's completely unbelievable if you've got any distance from it at all. We accept that urban waterways are often dirty […] But the Gowanus is literally a toxic, radioactive waste dump that the federal government says requires half a billion dollars to become tolerable.”

The tone taken by many journalists seems almost to imply that the canal is somehow both inherently and irreparably filthy. In October of last year Business Insider ran an article titled 9 Horrifying Things about Brooklyn's Gowanus Canal, which highlighted some key elements of Nosowitz's article, painting a very bleak picture indeed.  A New York Times piece on ongoing industrial activities along the canal's banks lingered pointedly on the canal's smell and the image of heaps of scrap metal being moved by a crane, leaving readers with the impression that the EPA's cleanup efforts will be a long, uphill, and possibly fruitless battle against stubborn polluters.

It's true; there's a lot to be horrified by in the Gowanus Canal. But for those living in the surrounding neighborhoods, the Gowanus is more than a joke or an irony or a metaphor for human folly; it's a toxic site that exists right in their backyards. In the wake of 2012's Superstorm Sandy, the Gowanus overflowed its banks, bringing its hazardous waters into the streets and seeping into basements. Yet rather than penning articles with titles like “9 Things You Can Do to Save the Gowanus Canal,” the common reaction among the press seems to be to throw up their hands and declare the canal beyond hope.

In the face of what seems to be an overwhelming task, it's easy for the average citizen to feel powerless. But believe it or not, the EPA is not the only organization actively taking steps to rehab the canal. Since 2006 the nonprofit Gowanus Canal Conservancy (GCC) has encouraged local residents to get involved with stewardship of the canal through a wide variety of volunteer activities designed specifically to benefit the canal and the surrounding neighborhoods. GCC's efforts approach the Gowanus Canal not as a danger to be avoided but as a rallying point to bring concerned citizens together. Natasia Sidarta, the conservancy's program manager, says she's seen been tremendous community interest in the canal, particularly after the Superfund designation drew attention to just how serious the situation is. “It is sort of an unsaid mission that we see this canal as a huge potential for community revitalization,” said Sidarta.

Many of GCC's projects address specific issues that threaten the canal, and over time these projects have the potential to bring about real, quantitative results. Through community gardens and a tree management programs, the GCC hopes to improve air quality and reduce storm water runoff into the canal. Plans are currently underway to construct six bioswales along a nearby side street. “It's essentially like a high functioning retention tank for storm water,” explains Sidarta. “It looks like a normal garden, but underneath is different kinds of soil mixtures and special gravel and permeable pavement that retains storm water.” The bioswales are designed to collectively capture and hold the first inch rainfall during a storm, further limiting runoff into the canal and reducing the amount of rain water that drains into the sewer, resulting in sewer overflows. 

Other projects are a little more whimsical. About three years ago the conservancy began experimenting with floating gardens built from repurposed debris such as old tires, bottles, buckets, and wood platforms. “We're experimenting with bioremediation and seeing what kind of plants can grow in the canal and seeing what kind of wildlife we can see on the gardens,” says Sidarta,.“We've seen herons and egrets and crabs and small fish gather around.” According to the project's web page, the gardens can also serve as surfaces for mussels and oysters to cling to, both of which, like the plants themselves, act as natural biofilters.  “It's sort of been this annual celebration of what volunteers can do,” said Sidarta.

Of course, community efforts alone are insufficient to tackle the extensive -- and expensive -- damage a century's worth of abuse has done to the canal. In fact, it was community groups like GCC, along with Friends and Residents of Greater Gowanus (FROGG) that first reached out to the EPA, urging the federal agency to take over where tepid city efforts had stalled. GCC remains actively involved in the ongoing public discussions surrounding the EPA's cleanup plans. “We kind of consider ourselves like the watchdog of the Gowanus Canal cleanup process,” says Sidarta, noting that the community will continue to have input throughout the cleanup. “I think [the EPA has] been very responsive to comments from the community, so I think the cleanup will be very comprehensive.”

Beyond Brooklyn

The Gowanus Canal is unique in many ways, but its story is universal. As of January 2014, there were 1,319 sites on the EPA's National Priorities List still undergoing or awaiting cleanup, and there are likely many more that haven't yet appeared on the EPA's radar. After all, it wasn't until 2010, some 30 years after the Superfund program was established, that the Gowanus Canal made the list, and that was at the urging of concerned citizens who'd decided enough was enough.

The ultimate fate of the Gowanus Canal, of course, remains to be seen. The contamination didn't happen overnight, and neither will the cleanup; it could take years of even decades of work and maintenance to transform the chemical waste dump into a thriving ecosystem. But if the story of the Gowanus Canal illustrates anything, it's that even the most polluted sites in some of the country's most populous neighborhoods need community advocates in order to be remedied.

So what might an article on how the average person can help restore a Superfund site read like? Getting informed is a crucial first step. Whether you're curious about an active cleanup site or worried about that cache of suspicious-looking barrels you discovered in the woods near your house, the EPA offers numerous resources for eco-minded individuals to voice their concerns and learn what they can do to help. If you’re lucky, you might find there are already groups working to repair environmental damage in the community; if not, now might be the time to start one.

To learn about a Superfund site near you, visit the EPA's Superfund Sites Where You Live page.

Additional Sources:

“Under the Gowanus Canal, Flushing Out the Stench,” New York Times, February 23, 2011

“Gowanus Canal Superfund,” United States Environmental Protection Agency, November 22, 2013