Updated
Memphis drinks rain that fell centuries ago
Most big Southern cities pull water from rivers and reservoirs. Memphis, sitting right beside the Mississippi, doesn't use the river at all. Memphis Light, Gas and Water pumps its entire supply from deep under Shelby County, and the water needs very little treatment.
Layers of the aquifer
The Memphis Sand Aquifer lies under layers of Mississippi River alluvium, loess, terrace deposits and clay. Below it are the deeper Fort Pillow Sand and Coffee Sand aquifers. MLGW's wells draw from depths of 350 to 1,100 feet. On an average day they deliver 120 million gallons to 10 pumping stations around the city. The report describes the sand and clay layers as a natural filter and cites experts who believe the water being drunk today fell as rain more than 2,000 years ago.
Treatment is short: aeration, sand filtration, disinfection, fluoride and corrosion control. MLGW's Water Quality Assurance Laboratory runs about 40,000 tests a year.
2025 results
| Measure | Average | Range |
|---|---|---|
| Hardness | 48 ppm (2.8 gpg) | 14–150 ppm |
| Alkalinity | 57 ppm | 21–158 ppm |
| pH | 7.3 | 6.2–7.9 |
| Sodium | 8.9 ppm | 6.0–14.7 ppm |
| Nitrate (as N) | 0.10 ppm | 0.01–0.32 (limit 10) |
| Fluoride | 0.59 ppm | 0.09–1.16 (limit 4) |
| Total trihalomethanes | 9.36 ppb | 2.06–26.69 (limit 80) |
| HAA5 | 1.29 ppb | 0.01–4.13 (limit 60) |
Disinfection byproducts form when chlorine reacts with organic matter, and deep groundwater carries very little of it. That's why Memphis's trihalomethane average is roughly a tenth of the federal limit, well below what river-fed cities typically report. The low sodium matters too for people on salt-restricted diets.
Fluoride history
MLGW began fluoridating under a City of Memphis ordinance at 1.0 ppm. In 2010 the U.S. Department of Health and Human Services proposed lowering the recommended level to 0.7 mg/L. TennesseeThe 2025 average in Memphis was 0.59 ppm.apos;s environment department made the same recommendation, and in 2013 MLGW lowered its target from 1.0 to 0.7 mg/L. The 2025 average in Memphis was 0.59 ppm.
Lead
Soft water with modest alkalinity can be aggressive toward metal pipes, so MLGW adds phosphate (0.75 ppm average) to coat them. The latest lead round, from 2024, tested 55 homes, most with some lead in their plumbing. No home was above the lead or copper action level. The 90th percentiles were 4.73 ppb for lead and 0.34 ppm for copper. MLGW's advice is to flush the tap for several minutes after water has sat. Showering or running laundry counts. Boiling water doesn't remove lead. For extra protection, see our lead and PFAS filter selector.
Protecting the aquifer
Because Memphis has no second source, the utility asks residents to help protect the aquifer. Its suggestions are to fix leaks, use efficient appliances, take part in river and stream clean-ups, and dispose of chemicals properly so they don't seep into recharge areas. If you're paying for bottled water in Memphis, our filter vs bottled calculator will probably show the money is better spent elsewhere.
Common Memphis questions
Is Memphis water really all groundwater?
Yes. MLGW says Memphis is one of the few cities whose supply comes entirely from groundwater. Wells 350 to 1,100 feet deep tap the Memphis Sand Aquifer, which sits beneath layers of clay, loess and alluvium.
Is Memphis water hard?
No, it's soft. Average hardness in 2025 was 48 ppm (2.8 grains per gallon), though individual samples ranged from 14 to 150 ppm (0.8–8.8 gpg) depending on the well field. Most homes don't need a softener.
Why add phosphate to such clean water?
Soft, low-alkalinity groundwater can slowly dissolve metal plumbing. MLGW adds phosphate (averaging 0.75 ppm in 2025) as a corrosion-control additive to protect pipes and keep lead and copper out of tap water.
How do I get my Memphis water tested for lead?
Call the MLGW water lab at 901-320-3962.
Where these figures come from
Reviewed November 1, 2026 against the sources above. Public water system ID TN0000450 (Memphis Light, Gas and Water (MLGW)). Figures describe the utility's system, not your home's plumbing; a certified lab test tells you what comes out of your tap. Spot an error? Tell us.