HARLEM — An agreement to invest more than $3.8 billion over the next 18 years to prevent untreated sewage from flowing into the city's waterways has been reached by the city and New York state.
Under the agreement with the Department of Environmental Conservation, New York City will invest the money to improve both gray and green infrastructure to prevent water runoff from entering the waterways.
Systems such as green roofs, tree pits and porous pavement parking lots which absorb water and prevent it from flowing into the sewer system would be used. Cost effective gray infrastructure such as holding tanks that allow the water to pool underground before being dissipated will also be utilized to a lesser extent.
Department of Environmental Protection Commissioner Carter Strickland said the agreement "represents a breakthrough in how we re-envision stormwater management."
Environmental watchdogs agreed.
"This is a watershed event, a landmark in making progress in cleaning up New York City's waterways," Larry Levine, a senior lawyer with the Natural Resources Defense Council, told DNAinfo.
"This is the first time it is legally locked in for the city to make significant investments in green investment. That distinguishes New York from everywhere else in the country."
The new agreement modifies an earlier 2005 agreement between the city and the DEC and allows it to shift some resources from gray infrastructure like holding tanks to green infrastructure, such as the porous parking lots.
It also establishes fines if the city does not meet certain goals.
Paul Gallay, President of Hudson Riverkeeper, said the agreement “will radically change our approach to reducing sewage pollution in New York City."
The issue gained public notice in July of 2011 after a fire and explosion at Harlem's North River Wastewater Treatment Plant caused 200 million gallons of raw sewage to flow into the Hudson River. Environmental activists said the flow of raw sewage into the Hudson from the plant was not unusual.
Wastewater treatment plants regularly expel sewage into the city's waters because the city's antiquated combined sewer system transports both rainwater and sewage for treatment.
When it rains, the volume of water headed to the city's sewage treatment plants increases. To prevent the facilities from becoming overburdened, the mixture of polluted rainwater and sewage is jettisoned into waterways such as the Hudson River.
The North River plant alone expels some 800 million gallons of untreated runoff into the Hudson. Each year, more than 30 billion gallons of untreated sewage hits the city's waterways.
"This is intended to help with the day-to-day, common place situation of raw sewage being discharged when it rains," said Levine.
"Because of the way the sewer system is designed, the best way to do that is to have plants and soil that act like a sponge to suck up water before it enters the sewer," said Levine.
With the new green infrastructure changes, 1.5 billion gallons of sewer overflow will be removed each year by 2030.
“New York City recognizes that green infrastructure — which stops rain where it falls — is the smartest way to reduce water pollution from storms," said NRDC Executive Director Peter Lehner.
"By making the cityscape literally greener, New York will make its rivers cleaner too — and with much greater return on investment than conventional solutions."
After the incident at the North River plant, state Sen. Adriano Espaillat proposed legislation that would require the Department of Environmental Protection to notify area residents and those who use the city's waterways when sewage is expelled into the waterways.
The bill is still pending.
On Monday, the New York League of Conservation Voters announced its list of top priorities and a sewage notification law was among them.
“Sewage contamination of our waterways is not only a threat to human health, it also compromises the well-being of the entire New York Harbor ecosystem," said Marcia Bystryn, president of the New York League of Conservation Voters.
Despite the announcement, Levine said a sewage notification law was still necessary. The DEP has promised to initiate an alert system to notify the public when sewage enters the waterways.
"There is definitely a need for improved public notification," said Levine.
"This project is not going to make the problem go away overnight and solving it is going to take time. A lot of other cities are doing a better job than New York has done so far in routinely alerting the public when sewage is in the water."