It was the city's highest-profile sewage disaster in years, but whether it was the worst is a matter for debate. Another– though less spectacular – candidate for that honor is the ongoing overflow of sewage and stormwater runoff that happens as a matter of course whenever there is heavy rain.
These releases, known as combined sewer overflows, or CSOs, stem from an antiquated city sewage system that channels household waste and storm runoff through the same pipes. When rainwater washing in from city streets fills the sewage system and threatens to overwhelm the treatment plants at the end of those pipes, officials divert the mixture into the city's rivers and bays.
The release is not as concentrated as the undiluted sewage from the North River spill, but it is dirty in other ways – besides the sewage, the storm runoff contains trash and chemicals from streets and storm drains. Also, there is more of it: about 27 billion gallons, or roughly 320 of those same oil tankers, into New York Harbor alone each year.
The good news, city officials say, is that they are working on the problem. In May, a $400 million facility opened at Paedergat Basin, in Brooklyn, that will temporarily store overflow in holding tanks underground, preventing the discharge of some 1.2 billion gallons a year into Jamaica Bay. Moreover, last September the city's Department of Environmental Protection unveiled its Green Infrastructure Plan, which aims to reduce overflows even further by stemming runoffs, using features like green roofs and permeable sidewalks on public and private sites around the city.
The bad news – aside from the hundreds of gallons of sewage and storm runoff in the water every year – is that implementing the plan will take time, and environmental advocates are raising questions about major parts of the city's approach. That, they say, fits with the overall story of water quality in the city – one of tentative steps forward against the backdrop of a queasily familiar status quo.
Plan faces hurdles
The Green Infrastructure Plan aims to reduce CSO volume by more than 12 billion gallons a year by the time it is fully implemented – a process that would take 20 years. Before the clock starts ticking on that implementation window, though, the plan must clear several procedural hurdles.
One is with the state Department of Environmental Conservation, which regulates city-run sewage treatment plants and the city's CSO abatement program, and which must grant its approval for the city to incorporate the Green Infrastructure Plan by amending existing rules. Negotiations between the city and state surrounding that approval are confidential, a DEC spokesman says, and have been going on for the last year. They are expected to yield a draft version of the new regulations soon, the spokesman says.
Even on matters that do not require state approval, the process of translating the concepts and broad goals of the Green Infrastructure Plan into detailed, binding law is laborious. Because much of the land where green infrastructure components can be installed is privately owned, the city is proposing an extensive set of incentives and regulations aimed at encouraging better stormwater control on private property. Many of the requirements – which would apply to new developments and modifications of existing buildings – are still in draft form, in a Department of Environmental Protection document called "Guidelines for the Design and Construction of Stormwater Management Systems.”



