Superstorm Sandy sent 11 billion gallons of sewage from East Coast treatment plants into streams, canals or roadways, according to a report.
That total is equal to New York’s Central Park stacked 41 feet high with sewage. More than 90 percent of the spills occurred in New York and New Jersey, where the storm made landfall six months ago. Of the total, 3.45 billion gallons was raw, untreated and unfiltered, said the report, which was based on state and federal data and estimates in cases where electronic monitors failed. The remainder was partially treated.
“What we learned is just how vulnerable this system is to floods, storms and climate change,” Alyson Kenward, the report author and a researcher at Climate Central, said on a conference call today. “Our system isn’t designed to handle these kinds of storm surges and the sea-level rise associated with climate change.”
Climate Central, based in Princeton, New Jersey, says it provides research on global warming for policy makers and the public.
Sewage plants are typically placed in low-lying areas, near water bodies, so that treated sewage can be easily released. As a result, plants are vulnerable to storm surges and coastal flooding, which is increasing because of global warming, according to the scientists responsible for the study. Coastal flooding is linked to 94 percent of the sewage that overflowed.
In many municipal systems, domestic and industrial sewage gets mixed with storm water in a single pipe, and the combined wastewater goes to a treatment plant before being released into rivers or other waterways, according to the report.
New York state will need to spend about $2 billion repairing water-treatment plants damaged by the October storm, and New Jersey plans to allocate $1 billion on repairs and additional funds shoring up plants in preparation for the next storm, according to Climate Central.
Sandy came ashore in New Jersey as a hybrid storm hours after merging with a frontal system off the East Coast. Its surge flooded parts of New York City and the New Jersey shore. In addition to 72 deaths from the storm, 87 people died in its aftermath, the National Hurricane Center said.
Sandy is blamed for destroying or damaging 650,000 homes and knocking out power to 8.5 million customers, some for weeks. It was the second-costliest system since 1900, after Hurricane Katrina in 2005, according to the center.
Sandy became the 77th name retired from the list of tropical storm names and will be replaced by Sara beginning in 2018. Hurricane names are reused every six years. If a storm is particularly deadly or damaging, the name may be dropped to avoid confusion and show respect for the victims.
The Climate Center developed an online, interactive graphic to let Mid-Atlantic residents check releases from specific plants, the types of overflows and causes.
Kenward said that the report is not meant as a criticism to those operating the plants across the region. Instead, it’s meant to show the vulnerability to storms, given the rising sea levels and increasing intensity of storms.