New York City wants to curb water runoff that sends sewage into city waterways through the use of “blue” roofs that have a series of drainage pools and “green” or grass- or ivy-covered roofs, reports Reuters.
The new plan, called “NYC Green Infrastructure” (PDF), would replace the existing approach for sewer overflow control with a mix of green and traditional infrastructure measures that are expected to reduce sewer overflows into waterways, reports Sustainable Business.
Mayor Michael Bloomberg told Reuters that he estimates the city could save $2.4 billion over 20 years if the state allows it to use this ‘green’ technology instead of a “grey infrastructure” strategy that includes the use of storage tanks and tunnels.
Currently, during heavy storms, bypasses are activated at the city’s 14 wastewater treatment plants to prevent flooding, which sends sewage into the city’s harbors, canals and rivers, reports Reuters. “Our PlaNYC goal of making 90 percent of City waterways suitable for recreations requires us to do more, and that means reducing the combined sewer overflows that have plagued the City for decades,” said Bloomberg in a statement.
Other green infrastructure measures cited by Reuters include the adoption of rain barrels and porous parking lots that could capture an inch of rain in 10 percent of the older neighborhoods, and sidewalks planted with strips of greenery that also could absorb rainwater.
Bloomberg said in the article that this ‘green’ water strategy could reduce sewer overflows into waterways 40 percent by 2030, and curb increases in water bills paid by businesses and residents.
If the state rejects his plan, the city would have to spend $6.8 billion to fix the problem of flooded treatment plants, reports Reuters.