Shelby County, Tennessee: drinking water report. Shelby County – Memphis – serves about 930,000 residents from one of the most enviable water sources in
Shelby County – Memphis – serves about 930,000 residents from one of the most enviable water sources in the country: the Memphis Sand Aquifer. This deep, confined aquifer produces naturally clean, soft water that requires minimal treatment. Memphis Light, Gas and Water (MLGW) operates over 160 wells drawing from the aquifer, and the water is so clean that it is typically only chlorinated before distribution – no filtration plant needed.
The Memphis Sand Aquifer sits 350 to 1,100 feet below the surface, protected by thick clay layers that filter out most surface contamination. For decades, this made Memphis water among the cleanest in any major US city. But that protection is not absolute. A 2019 University of Memphis study found that the clay layer has gaps – particularly near the Davis wellfield in south Memphis – that allow surface contamination to reach the aquifer faster than previously believed.
UCMR5 data shows low-level PFAS detections in the MLGW system. The Millington Naval facility and former Defense Depot Memphis are potential PFAS sources. According to the Tennessee Department of Environment and Conservation's 2024 monitoring data, PFAS levels in the MLGW system remained below proposed federal MCLs, but the discovery of clay layer breaches has increased concern about long-term aquifer vulnerability.
Memphis water starts with a major advantage – a deep, naturally filtered source. But complacency based on the aquifer's reputation may mask emerging risks from PFAS and aquifer vulnerability.
Check your water for current monitoring data. Even in Memphis, a basic activated carbon filter improves any remaining chlorine taste. For PFAS, reverse osmosis adds a layer of protection. Our water filter guide covers options. Pull your detailed report, and visit our Tennessee page for statewide context.
Drinking water is one exposure route. These federal datasets also cover Shelby County, TN.
The EPA places Shelby County, TN in Zone 3 - the EPA's lowest-risk category, with a predicted average indoor radon level below 2 pCi/L. Zone maps predict an area's radon potential from geology and existing indoor readings; they say nothing about a specific house. Testing is the only way to know your own level.
56% of homes in Shelby County, TN were built before 1980, and 12% before 1950. Residential lead paint was banned in 1978, so housing age is the strongest available proxy for lead-paint exposure. This describes the county's housing stock, not any one home.
Modelled annual fine-particle pollution (PM2.5) in Shelby County, TN averages 8.7 µg/m³, within the EPA's annual standard of 9 µg/m³. These are CDC modelled county estimates rather than readings from a specific monitor.
How radon zones work · Air quality by county · Lead exposure guide