DeKalb Watershed Management staff are inspecting lift stations to prevent future sewage spills after a power failure caused almost half a million gallons of raw sewage to spill into a Lithonia waterway on May 8.

County staff discovered the 484,089-gallon spill at 7134 Maddox Road at about 11 a.m., during a routine inspection.

Two of the three pumps in the lift station had stopped working during a power failure, causing the spill into Swift Creek.

The county says residents are not at risk.

“County crews immediately cleaned the area, which included removing debris associated with the spill and disinfecting the area,” spokeswoman Suzanne Forte said May 15. “On the day of the spill, residents in the area were advised to avoid the site and keep pets from the waterway until the spill was contained.”

Staff stopped the spill about 10:30 p.m.

Forte said a boil water advisory was not issued because the spill did not affect the drinking water system.

“The county is proactively inspecting lift stations to prevent future spills,” she said. “There are no long-term risks.”

She said the county is committed to reducing sanitary sewer spills and has made routine inspections, proper maintenance and repairs a priority.

This year, the county is investing $79 million in sewer maintenance and repairs, set to begin in June, as part of its obligation to honor an 8.5-year clean water consent decree with state and federal governments.

The $1.345 billion consent decree, an enforcement action initiated in 2009 by the U.S. Environmental Protection Agency and the Georgia Environmental Protection Division, became federal law in December 2011.

It requires DeKalb to clean, repair, enlarge and maintain its network of over 2,600 miles of sewer pipes to reduce and prevent overflows by June 2020.

Between 2006 and October 2010 there were 836 spills from DeKalb’s broken manholes and clogged sewer lines.

The county’s 50-year-old sewer system includes 55,000 manhole covers and 66 lift stations.

“In addition to infrastructure improvements, the county has hired more staff to proactively report, locate and respond to spills and protect the environment,” Forte said.

DeKalb’s sanitary sewer overflows – about 60 percent of which are caused by fats, oils and grease being poured down drains and sinks –have declined 31 percent during the first quarter of 2018, compared to the same period last year.

Almost 11 million gallons of raw sewage were dumped into creeks near Lithonia and Brookhaven as a result of two spills in August 2017 alone.