January 28, 2011

CONTACT:

Farrell Sklerov / Michael Saucier (718) 595-6600

DEP Launches Parking Lot Stormwater Pilot Program

Initiative Will Require Parking-Lot Owners to Pay for Wastewater Services

Environmental Protection Commissioner Cas Holloway today announced the launch of the Stormwater Pilot Program for stand-alone parking lots, an initiative that requires lot owners to pay a charge for the stormwater runoff they produce, or demonstrate that they are addressing stormwater on site with green infrastructure or other measures. Stormwater is generated from rain and melting snow, which is conveyed over impervious surfaces such as rooftops, parking lots, and sidewalks into New York City’s sewers, rather than being absorbed into the ground. New York City’s 835,000 customers already pay for wastewater charges as part of their quarterly bill. Until now, stand-alone parking lots, which produce a significant amount of stormwater runoff that can lead to combined sewer overflows during heavy rain, have not contributed financially to the system because they did not receive a water bill. New York City, like other older urban centers, is largely serviced by a combined sewer system where stormwater and wastewater are carried through a single pipe. During heavy storms, the system often reaches capacity and must discharge a mix of stormwater and wastewater—called a combined sewer overflow, or CSO—into New York Harbor. This Stormwater Pilot Program was a component of the Fiscal Year 2011 Water Rate, and it complements the NYC Green Infrastructure Plan, a multi-pronged strategy that relies on $2.4 billion of green infrastructure to capture stormwater, unveiled by Mayor Bloomberg last September.

“Keeping New York Harbor clean requires substantial investments that need to be funded by everyone who benefits from our water and sewer system,” said Commissioner Holloway. “Until now, stand-alone parking lots have not contributed their fair share, even though they are the source of a tremendous amount of stormwater runoff. The free-riding days are over. This new pilot program will require stand-alone parking lots to pay for their fair share of wastewater services. If a lot owner demonstrates that their lot already absorbs or retains a sufficient amount of stormwater, they will be exempt from the charge. This pilot is an important step in the implementation of the NYC Green Infrastructure Plan that Mayor Bloomberg announced last September that will dramatically reduce combined sewer overflows and improve water quality for all New Yorkers.”

Parking lots of all types make up 6% of New York City’s impervious area, and during a one-inch storm, one acre of impervious surface generates roughly 27,000 gallons of stormwater runoff. Parking lots can reduce the amount of stormwater runoff by incorporating porous asphalt, catch basins, swales or subsurface detention systems. The new provision will require the 267 stand-alone parking lots with no water service to pay $0.05 per square foot for wastewater services, an average of $669 a year per lot. Lots that demonstrate the ability to capture stormwater and prevent it from entering the wastewater system can apply for an exemption from the charge. This waiver incentivizes investing in different types of green infrastructure that have the ability to capture and retain stormwater runoff before it enters the sewer system, thereby reducing the likelihood and intensity of combined sewer overflows.

Two-thirds of New York City has a combined sewer system that collects wastewater and stormwater runoff together in the same pipe from properties and streets. This often presents an issue during rainstorms when treatment plants can reach their capacity. To relieve the sewage system during these high-flow periods, the interceptor sewers have “regulators” equipped with overflow weirs that divert combined stormwater and wastewater into New York City’s surrounding waterways. This is known as a combined sewer overflow. Upgrades to our plants and sewers have allowed us to capture a greater amount of overall flow, from about 30% in the 1980s to over 72% today, and overflows are now more dilute, with the percentage of sanitary waste decreasing from 30% to about 12% today.

Most green infrastructure uses natural features, like green-roofs, and adds structural designs, like porous pavement and tree pits, to absorb and retain stormwater. By combining the current “grey” strategy with the “green” strategy outlined in the Green Infrastructure Plan, the City will cut CSOs by more than 12 billion gallons per year by 2030—a 40% reduction—which is two billion gallons more per year than under the current plan. If endorsed by the State, the Green Infrastructure Plan will cost New Yorkers $2.4 billion less than the existing “grey” plan where all CSO overflows are addressed by the construction of “grey” tanks and tunnels.

Green infrastructure uses vegetation, soils, and other structural elements to mimic natural hydrologic cycles by slowing down, absorbing and evaporating stormwater. These characteristics, the minimal energy and manpower required for operation, and the relatively quick installation mean that green infrastructure can be cost-effective and provide immediate benefits. Types of green infrastructure projects include: blue roofs and green roofs for new and existing buildings that slow roof water from draining from roofs too quickly and overwhelming storm sewers; porous pavement for parking lots that allows water to seep through it and be absorbed into the ground rather than becoming runoff; tree pits and streetside swales for roadways that allow water to pool in underground holding areas until it can dissipate in the ground or transpire through plants; wetlands and swales for parks; rain barrels for low-density residential areas; and a compilation of these techniques for high-density residential housing and other developments.

Once approved, the Green Infrastructure Plan will invest a total of $5.3 billion in a mix of green infrastructure, cost-effective grey infrastructure, system-wide optimization, and conservation. This multi-pronged strategy will result in a net reduction in combined sewer overflows of roughly 12 billion gallons per year. By capturing the first inch of rain on 1.5% of impervious surfaces by 2015, an additional 2.5% by 2020, an additional 3% by 2025 and the remaining 3% by 2030, the green element of the plan will reduce combined sewer overflows by 1.5 billion gallons per year.