Rock County Rural Water System, MN
Lead detected, under the action levels
Latest 90th-percentile lead: 1 ppb (monitoring period 2026-2026). 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
Rock County Rural Water System serves about 2,919 people through 821 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 surface water, in Rock County, Minnesota. EPA system ID: MN1670007; phone on file: 5072838886. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Lead results over time
Against the period ending 2025 (0 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Rock County Rural Water System is 5 ppb across 10 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 1 ppb |
| 2025 | 0 (not detected) |
| 2025 | 1 ppb |
| 2024 | 1 ppb |
| 2022 | 4 ppb |
| 2021 | 2 ppb |
| 2021 | 2 ppb |
| 2017 | 5 ppb |
| 2016 | 4 ppb |
| 2016 | 4 ppb |
Where this result ranks
Of the 966 Minnesota systems with a lead result, the median latest reading is 0 ppb; 7 are over 15 ppb right now and 48 have gone over at some point. Rock County Rural Water System's 1 ppb sits at the 61st percentile in Minnesota and the 54th nationally (higher means more lead).
Nearby utilities
7 other systems share Rock County; 4 of them have a higher latest lead result than Rock County Rural Water System. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Luverne | 4,946 | 5 ppb |
| Hills | 685 | 0 (not detected) |
| Beaver Creek | 297 | 2 ppb |
| Magnolia | 214 | 0 (not detected) |
| Hardwick | 198 | 3 ppb |
| Steen | 180 | 0 (not detected) |
| Kenneth | 56 | 2 ppb |
Your move
Test your own tap with a certified lab first-draw sample; Luverne, MN 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 Rock County Rural Water System whether it covers that cost before hiring anyone - many utilities now do. Its latest copper 90th percentile is 1610 ppb (copper action level 1,300 ppb).
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. Systems that went over once often dip back under; here is what that means.