A temporary system that will pump oxygen into the Gowanus Canal will also inject recreational opportunities along the still-fetid waterway, officials insisted this week.
Yesterday, engineers with the Department of Environmental Protection activated a new oxygenation system for the waterway, and disabled its 110-year-old flushing tunnel, which will be renovated as part of a city-led $140-million project that will ultimately improve the canal’s water quality.
Cas Holloway, the city’s environmental commissioner, predicted great things once the work is complete in 2013.
“This upgrade will open up new recreational opportunities and significantly improve the quality of life of those who live nearby,” he said.
Later, a spokeswoman said that the canal is expected to meet standards for boating and fishing in two years.
A push of a button at the Gowanus pumping station at the foot of Douglass Street lowered a divider between the flushing tunnel and the canal, shutting down the tube, which pulled water from oxygen-rich Buttermilk Channel to the waterway.
Ultimately, the single pump will be replaced by three pumps, increasing the daily flow of cleaner water into the canal from 154 million gallons a day to 215 million gallons a day.
As the renovations proceed, millions of gallons of canal water will be supersaturated with oxygen in the chamber each day, and then discharged back into the canal, recently designated a Superfund site, a testament to the pollution that makes it one of the most toxic waterways in the nation.
The oxygen for the system is pulled out of the air, compressed and sent through underground pipes to a conical chamber standing alongside the canal’s edge. The 2,500-feet of piping is below the canal’s greasy surface, and marked by white buoys which warn passing vessels not to damage the gas network.
The canal’s rotten egg stink is the result of stagnant water with low dissolved oxygen, a condition that gives rise to bacteria and other simple organisms to produce hydrogen sulfide.
The oxygenation system is the result of a state order issued in 2005 to improve the water quality of the canal. The city’s plan was approved last year.
When the work is completed, fewer perceptible odors will be detected along the waterway, officials said.
That’s good news for residents like Marlene Donnelly, a member of the group Friends and Residents of the Greater Gowanus. “There was great concern that the work would make this area unbearable, but this will definitely make this habitable,” she said. “We have to live here with this air.”