So, just how polluted is the Gowanus?
Beginning in 1869, the Gowanus Canal was a major shipping route for coal yards, gas plants, soap factories, sulfur producers, and many other industries; each with their own unique hazardous byproducts. In addition, sewers from neighborhoods far and wide drain into the canal.
In 1955 the US Army Corp of Engineers first dredged the canal, but soon after abandoned the project due to the high costs.
In March, 2010, the US Environmental Protection Agency designated the Gowanus a federal Superfund Site, estimated cleanup costs in excess of $300 million, and a projected duration of nine years.