Columbia, South Carolina — the state capital — sits at the confluence of the Broad and Saluda Rivers, which merge to form the Congaree River. The city’s drinking water comes primarily from Lake Murray (a Saluda River reservoir) and the Broad River, serving about 375,000 people in the metro area through multiple water utilities.
The source water is generally good. Lake Murray, impounded behind Saluda Dam in 1930, provides a large, relatively clean reservoir. But Columbia’s water story includes some serious chapters — most notably the catastrophic 2015 flood that exposed the fragility of the region’s water infrastructure.
The 2015 Flood: A System-Breaking Event
In October 2015, a stalled weather system dumped over 20 inches of rain on the Columbia area in just a few days. The resulting flood was historic — breaching more than 30 dams, overwhelming the water treatment system, and contaminating the drinking water supply.
Columbia’s water treatment plant on the Broad River was inundated. The city issued a boil water advisory that lasted for days, and some areas went without running water entirely. The event revealed the vulnerability of a water system built along river floodplains — exactly where the water sources are but also where flood damage is worst.
Since 2015, Columbia has invested in infrastructure improvements including backup water supply interconnections, treatment plant hardening, and improved flood monitoring. But climate projections suggest extreme rainfall events will become more frequent in the Southeast, meaning the risk isn’t going away.
Fort Jackson PFAS
Fort Jackson, the U.S. Army’s largest basic training installation, sits on Columbia’s eastern edge. Like virtually every military installation in the country, Fort Jackson used AFFF firefighting foam for training and emergencies. PFAS contamination has been detected in groundwater on and near the base.
The Army has been conducting investigation under the CERCLA framework. Some monitoring wells near Fort Jackson have shown PFAS levels above the EPA’s 4 ppt MCL for PFOA and PFOS. The extent of off-base migration is still being determined.
Columbia’s municipal water supply comes from surface sources (Lake Murray, Broad River) rather than local groundwater, so the Fort Jackson contamination doesn’t directly affect city water. But private well users in the Richland County areas east and southeast of the base should test for PFAS.
Aging Infrastructure
Columbia’s water and sewer infrastructure includes pipes dating back to the early 1900s. The city has experienced water main breaks, sewer overflows, and service disruptions — common problems in Southern cities that grew rapidly in the mid-20th century and then underinvested in maintenance.
Lead service lines exist in older neighborhoods, particularly in areas developed before 1950. Columbia Water has been working through its lead service line inventory and replacement program. The city uses corrosion control treatment to minimize lead leaching, and recent testing has shown 90th percentile lead levels below the EPA action level.
The sewer system has been under scrutiny. SC DHEC has issued enforcement actions related to sewer overflows, and the city has been investing in sewer rehabilitation. While sewer issues don’t directly affect drinking water, they indicate the overall condition of the underground infrastructure.
Lake Murray Water Quality
Lake Murray is a valued recreational resource and drinking water source. The lake’s water quality is monitored by the SC Department of Health and Environmental Control and generally meets standards, but development pressure around the shoreline has raised concerns about nutrient loading and stormwater runoff.
Algal blooms can occur in Lake Murray during warm months, particularly in coves with limited circulation. While the treatment plant can handle the taste and odor compounds produced by algae, blooms indicate nutrient enrichment that should be managed through watershed protection.
The lake also has legacy contamination from the now-closed Congaree River floodplain industrial sites upstream. Monitoring continues to ensure these don’t affect drinking water quality.
What Residents Can Do
- Prepare for floods. Keep emergency water supplies on hand. After major rain events, follow any boil water advisories immediately.
- Test for lead. Homes built before 1986 in older Columbia neighborhoods should test. Contact Columbia Water for information.
- Filter for taste and DBPs. Activated carbon handles the seasonal taste changes that come with surface water sources.
- Private well owners near Fort Jackson: Test for PFAS, bacteria, and nitrates. Don’t assume your well is clean because your neighbor’s is — contamination plumes are irregular.
- Conserve during droughts. Lake Murray’s level drops during dry periods, which can concentrate contaminants and stress the treatment system.
If you’re concerned about your water quality, a certified water treatment professional can test your water and advise on the best treatment approach.
See also our coverage of Charleston water quality and Chattanooga water quality.
Sources: Columbia Water, SC DHEC, EPA SDWIS, US Army Environmental Command, USGS