Midlands town spilled millions of gallons of sewer overflow into rivers in 2025
The town of Lexington spilled more than 7 million gallons of sewer overflow into Midlands-area rivers last year, according to an annual sewer overflow report published Wednesday.
The report, published by the Congaree Riverkeeper, found that Lexington was the worst offender last year for sanitary sewer overflows, which dump untreated sewage into river systems. The number of gallons spilled last year was more than double the amount spilled in 2024 and likely broke a record for the last decade, even rivaling the more than 5.6 million gallons dumped in 2015, the year of Columbia’s 1,000-year flood.
Municipal sewer spills can contaminate water and lead to ecological and public health issues. In 2025, the report noted more than 100 sewer overflows that dumped nearly 8 million gallons of untreated waste into local rivers. Some overflows were caused by flooding while others were caused by failures at sewage pump stations.
“When that sewage backs up because the pumps aren’t working, it has to go somewhere so it goes up and out and into a creek, usually the nearest creek,” Bill Stangler, the Congaree Riverkeeper, told The State.
The town, which has more than 135 wastewater stations and over 400 miles of sewer lines, is the county seat of Lexington County, which has grown exponentially in recent years. But infrastructure like roads and water and sewer systems have failed to keep up with the growth. South Carolina is the fastest growing state in the nation, according to U.S. Census data released Tuesday.
There were two large overflows that put Lexington at the top of this year’s list. In May, a massive rainstorm caused 1.3 million gallons of overflow to spill into the rivers. The town’s utilities director David Wiman said the storm was a one in 10-year event.
“The ground was already so saturated, so it just overwhelmed our pipes,” Wiman told The State.
The other, more significant overflow, happened in early August. An electrical storm knocked out power to one of the town’s sewer pump stations, causing 5.76 million gallons of waste to spill into 12 Mile and 14 Mile Creeks. A blown fuse at the station meant no alarms went off to alert town utilities employees of the overflow for hours.
“These are things that shouldn’t happen,” Stangler said. “There should be redundancies, there should be maintenance, there should be ways to avoid it. I know sometimes things happen, but the real test on any issue like this is, ‘What have you put in place since then to ensure it doesn’t happen again?’”
Wiman said after that event that the town reached out to the contractor of the alarm system and helped create a new alarm that will go off if the system’s readings stay in one place for too long. If the readings stay frozen for more than 10 or 15 minutes, the new system will alert the utilities staff. The town also gave two additional trainings to its utilities employees after the incident.
Aside from the millions of gallons it spilled into the area’s rivers, the report noted an additional 80,000 gallons spilt into Lake Murray. The town of Chapin spilled 120,000 gallons of untreated sewage into Lake Murray as well. The spills represent less than 1% of the amount of sewage the town treats every year. In 2025, Lexington collected and sent 2.54 billion gallons of sewage to the Cayce Regional Wastewater Treatment Plant, town officials said.
At a July 2025 meeting in which town council members and staff discussed the vision plan for the town going into 2026, Wiman told the council that its sewer system was not fully compliant with any of the state’s regulatory requirements.
In an interview with The State, Wiman said that his main priority for the utilities department for the upcoming fiscal year was to get funding for a hydraulic model that would help the town better prepare for incoming developments. Under its current system, Wiman’s staff has to make an educated guess at how new subdivisions will impact existing infrastructure.
Lexington County has added more 100,000 people to its population in the last decade and is expected to add another 30,000 residents by 2040, according to state population projections. The town’s sewer system serves customers inside and outside the town limits, the town’s spokesperson Laurin Barnes said, and is twice the size of the town’s water system.
This story was originally published January 29, 2026 at 2:51 PM.
