Columbia
Columbia, SC water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
columbia city of (sc4010001)
surface water (rivers/reservoirs) · local government · PWSID SC4010001
Below EPA's 15 ppb lead action level at last testing.
Source: EPA Safe Drinking Water Information System (SDWIS) · 2026 Q1
Columbia is a mid-sized city and the largest in South Carolina, home to roughly 133,803 residents. Columbia's drinking water comes largely from the same regional sources that serve South Carolina: rivers, reservoirs, and coastal aquifers.
As elsewhere in South Carolina, the central challenge is saltwater intrusion. Fast Lowcountry growth around Charleston pressures coastal aquifers and reuse planning.
South Carolina reuses an estimated 7% of its treated wastewater and maintains developing reuse programs; Columbia tracks severe to extreme drought conditions on the U.S. Drought Monitor scale.
Explore the South Carolina profile for statewide context, or dig into the water issues shaping Columbia below.
Richland County water quality
Source: EPA SDWIS · 2026 Q1
At a glance
- Population ~133,803 (largest in South Carolina)
- Primary sources: rivers, reservoirs, and coastal aquifers
- Drought: severe to extreme conditions
- State reuse rate: ~7% of wastewater
Statewide drought history
% of South Carolina in severe+ drought (Extreme (D3) now).
Source: U.S. Drought Monitor
Common questions
Is tap water safe in Columbia?
Columbia's largest water system, COLUMBIA CITY OF (SC4010001), serves about 319,500 people. EPA records show 2 health-based violation(s) since 2016 and a most-recent 90th-percentile lead level of 5 ppb (EPA action level is 15 ppb). Always check your own provider's annual Consumer Confidence Report.
Where does Columbia get its water?
COLUMBIA CITY OF (SC4010001) draws primarily from surface water (rivers/reservoirs), part of South Carolina's supply from rivers, reservoirs, coastal aquifers.
Related water issues
Saltwater Intrusion
As coastal aquifers are over-pumped and seas rise, saltwater pushes inland and contaminates freshwater supplies for cities from Florida to California.
ExploreAging Infrastructure
Much of America's water infrastructure is decades past its design life, leaking trillions of gallons a year and demanding hundreds of billions in reinvestment.
ExploreAgricultural Demand
Agriculture accounts for the majority of consumptive water use in the West, making farm efficiency and water markets central to any supply solution.
Explore