Hollow Rock Water Dept, TN
Lead detected, under the action levels
Latest 90th-percentile lead: 0.4 ppb (monitoring period 2026-2028). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. Lead was measured in sampled homes but the 90th percentile is under both action levels. EPA's health goal for lead is zero, so test your own tap if your home was built before 1986 or anyone in it is pregnant or a young child.
Who runs the water here
Hollow Rock Water Dept serves about 954 people through 389 service connections, which makes it a small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Carroll County, Tennessee. EPA system ID: TN0000310; phone on file: 731-586-7773. They can tell you what your service line is made of and whether they pay to replace it.
Every lead result on file
Against the period ending 2025 (0.2 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Hollow Rock Water Dept is 1 ppb across 5 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2028 | 0.4 ppb |
| 2025 | 0.2 ppb |
| 2022 | 0.1 ppb |
| 2019 | 0.36 ppb |
| 2016 | 1 ppb |
How Hollow Rock Water Dept compares
Of the 453 Tennessee systems with a lead result, the median latest reading is 1 ppb; 0 are over 15 ppb right now and 10 have gone over at some point. Hollow Rock Water Dept's 0.4 ppb sits at the 8th percentile in Tennessee and the 42nd nationally (higher means more lead).
Neighbouring systems
8 other systems share Carroll County; 3 of them have a higher latest lead result than Hollow Rock Water Dept. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Huntingdon Water Dept | 6,167 | 0.4 ppb |
| Mckenzie Water Dept | 5,464 | 0.2 ppb |
| Bruceton Water System | 1,649 | 0.2 ppb |
| Cedar Grove U.D. | 1,556 | 0.3 ppb |
| South Carroll Utility District | 1,549 | 4 ppb |
| Atwood Water System | 1,299 | 0.6 ppb |
| Trezevant Water System | 955 | 1.3 ppb |
| Mclemoresville Water Dept | 376 | 0.3 ppb |
Your move
Test your own tap with a certified lab first-draw sample; Hollow Rock, TN may offer free or low-cost kits through the utility. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Hollow Rock Water Dept whether it covers that cost before hiring anyone - many utilities now do.
These figures describe homes the utility sampled, not your tap. Only your service line record or a test of your own water answers the question for your house. What a 90th-percentile result does and does not tell you: how to read a lead result. The action level is dropping - the 10 ppb rule from 2027.