When Superstorm Sandy hit the coasts of New Jersey and New York, the huge influx of water had an effect that's only now been quantified: a huge outflow of polluted water from sewage treatment facilities.

Earlier today, Climate Central, a nonprofit research and journalism organization, released a report showing that more than 11 billion gallons of untreated or partially treated wastewater flowed into waterways from plants that had lost power, were overwhelmed by flooding, or had other problems. Overflows through manholes and other vulnerable points of sewage systems also were included in the report.

Climate Central looked at data from a variety of entities in eight states. By far, most of the overflows occurred in New Jersey and New York, which accounted for 93 percent of the spillage.

The largest single spill was the three billion gallons of partially treated wastewater that flowed from the Passaic Valley Sewerage Commission in Newark in the two weeks after the storm, when the plant was limping along. It came after an initial spill of 840 million gallons of untreated sewage into Newark Bay during the storm.

Most of the problems in New Jersey were in the northern part of the state. But some problems in this region included 1,000 gallons of untreated sewage flowing from a manhole on Caldwell Road in Cherry Hill, and another 1,000 gallons flowing from a manhole on Yarmouth Circle in Evesham Township.

Pennsylvania had far fewer problems, although 22.8 million gallons flowed from a treatment facility in Harrisburg that lost power during the storm.

"What we learned, and were surprised to find, was just how vulnerable these facilities were to storms," said Alyson Kenward, a Climate Central senior scientist who wrote the report.

But, in case the name of the organization wasn't enough of a hint, she and others also said the report highlighted how vulnerable the facilities are to climate change and sea level rise.

Most sewer systems are in low-lying areas along the coast, she said. Superstorm Sandy showed their vulnerability, and improvements should be made with climate change in mind, she said.

The Climate Central report noted that in many places, residents were told to boil their water before drinking it because of fears it was contaminated.

After the storm, New Jersey officials announced plans to allocate nearly $1 billion to repair damaged facilities and another $1.7 to make them more resilient to such severe events, the report said.