Unusually low rainfall helped Maine set a record for the least amount of sewage pollution into waterways last year, according to a new state report.
Maine has been trying to eliminate combined sewer outfalls in dozens of towns and cities for decades. During heavy rains, these older systems carry combined stormwater and raw sewage into rivers and coastal waters.
Last year, about 153 million gallons of mixed water was discharged from combined sewer outfalls, half as much as the previous lowest record, according to the Maine Department of Environmental Protection.
There were 143 discharges in 2025, about a hundred fewer than the previous record in 2024.
The Department of Environmental Protection’s Mike Riley said that flash drought conditions last year helped avoid polluting discharges. But he said that the hundreds of millions of dollars invested in removing combined sewer outfalls also made an impact.
For example, the gallons discharged per inch of rainfall also hit a low record last year, Riley said.
“That last number takes into account dry vs. wet years,” Riley explained. “And that still being the lowest on record is a sign that investments that the communities are making on these [combined sewer outfall] abatement projects continue to pay off.”
Towns and cities spent $55.5 million on combined sewer outfall work last year, according to the Department of Environmental Protection. Riley said that over the years many of the simpler projects have been fixed and those remaining are more expensive and complicated works.
This story appears through a media partnership with Maine Public.