11 Billion Gallons of Sandy Sewage Overflow
Explore where sewage overflows happened during Hurricane Sandy, what caused them, and how treated each overflow was.
Sandy caused more than 10.9 billion gallons of sewage overflows. Roll over each circle below to see the different size and location of each documented overflow.
Legend: Circles are color-coded by state sized according to the volume of overflow in gallons.
About 70 percent of the overflows contained partially treated sewage, which in most cases did not meet the national treatment wastewater standards. Most of these overflows were at least disinfected before being released into waterways, but in rare cases may only have been filtered.
About 30 percent of the overflows were entirely untreated before entering rivers, streams, or the ocean
Sandy's record storm surge inundated many coastal treatment plants and overloaded pipes and pumping stations. The storm surge flooded treatment tanks, knocked out power, caused mandatory evacuations in select neighborhoods, and forced plant operators to send partially treated and untreated sewage into nearby waterways.