More than 800,000 gallons of untreated sewage spilled from an Alabama city’s utility plant and eventually reached the Tennessee River during two days of heavy rains, documents filed by Decatur Utilities show.

Disclosures filed with the Alabama Department of Environmental Management reveal that about 8 million gallons of raw sewage have escaped the Decatur Utilities sanitary sewer system this year in 81 overflows, The Decatur Daily reported.

The largest discharge happened last week when rain overwhelmed old pipes and sewage began pouring from a manhole near the utility’s headquarters.

It took the city-owned company more than 40 hours to stop the overflow.

Decatur Utilities told the Environmental Department the heavy rains caused the problem, though the newspaper says similar companies in neighboring communities reported few to no sewer overflows during the same period. Officials were out for the holidays and didn’t respond to questions last week, Decatur Utilities spokesman Joe Holmes told the newspaper.

Water Resources Manager Tom Cleveland has said the company reports a high number of overflows because crews proactively look for them. The company has replaced aging infrastructure over the past six years in an effort to reduce overflows, he added.

In May, the state Attorney General’s Office and the Environmental Management Department sued Decatur Utilities, arguing it’s liable to the state for up to $25,000 per overflow.

The complaint alleges the spills have contributed to high E. coli levels in the Tennessee River.