Is Tennessee Tap Water Safe to Drink?
Water quality data for 20 cities across Tennessee. Find your city below.
Water quality in Tennessee varies significantly from city to city. Across 20 cities we track, hardness ranges from 15 PPM in Johnson City to 180 PPM in Collierville, with a statewide average of 96 PPM. 8 of 20 cities have hard water above 120 PPM where a water softener provides measurable benefits.
2 Tennessee cities have forever chemicals (PFAS) above the EPA's 2024 limit of 4 parts per trillion: Smyrna (52.32 ppt), Jackson (33.8 ppt). A reverse osmosis system or NSF P473-certified filter can reduce PFAS to safe levels.
Complete Tennessee Guide
Statewide water quality overview, costs, and treatment recommendations.
Well Water in Tennessee
Testing, treatment, and common issues for private wells.
Hardest Water Rankings
Tennessee cities ranked by water hardness level.
City Comparisons
Collierville vs Johnson City
Side-by-side water quality comparison.
Collierville vs Murfreesboro
Side-by-side water quality comparison.
Murfreesboro vs Franklin
Side-by-side water quality comparison.
Tennessee Cities by Water Hardness
| City | Hardness (PPM) | Level | PFAS (ppt) | Source |
|---|---|---|---|---|
| Collierville | 180 | Very Hard | 0 | Memphis Sand Aquifer |
| Murfreesboro | 161 | Hard | 21.4 | Percy Priest Reservoir |
| Franklin | 161 | Hard | 5.6 | Harpeth River |
| Clarksville | 140 | Hard | 0 | Cumberland River |
| Cookeville | 140 | Hard | 0 | Center Hill Lake & Falling Water Riv |
| Brentwood | 135 | Hard | 0 | Cumberland River (Metro Water) |
| Columbia | 120 | Hard | 3.2 | Duck River |
| Old Hickory | 120 | Hard | 0 | Old Hickory Lake (Cumberland River) |
| Smyrna | 115 | Moderately Hard | 52.32 | Percy Priest Reservoir |
| Nashville | 110 | Moderately Hard | 0 | Cumberland River |
| Hendersonville | 105 | Moderately Hard | 0 | Old Hickory Lake |
| Knoxville | 90 | Moderately Hard | 3.7 | Tennessee River + Fort Loudoun Lake |
| Chattanooga | 82 | Moderately Hard | 13.18 | Tennessee River |
| Jackson | 57 | Slightly Hard | 33.8 | South Fork Forked Deer River |
| Knoxville West | 55 | Slightly Hard | 3.7 | Fort Loudoun Lake |
| Germantown | 35 | Slightly Hard | 0 | Memphis Sand Aquifer |
| Chattanooga Downtown | 35 | Slightly Hard | 13.18 | Tennessee River |
| Memphis | 33 | Slightly Hard | 0 | Memphis Sand Aquifer |
| Maryville | 25 | Slightly Hard | 0 | Abrams Creek + Fort Loudoun |
| Johnson City | 15 | Soft | 0 | Watauga Lake, Boone Lake |