Hardin Subdivision, MT
Lead detected, under the action levels
Latest 90th-percentile lead: 1 ppb (monitoring period 2023-2025). 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.
Hardin Subdivision at a glance
Hardin Subdivision serves about 28 people through 11 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Gallatin County, Montana. EPA system ID: MT0004263; phone on file: 406-579-7851. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Lead results over time
Against the period ending 2022 (1.17 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Hardin Subdivision is 2 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 1 ppb |
| 2022 | 1.17 ppb |
| 2019 | 2 ppb |
| 2016 | 0 (not detected) |
How Hardin Subdivision compares
Of the 753 Montana systems with a lead result, the median latest reading is 1 ppb; 5 are over 15 ppb right now and 28 have gone over at some point. Hardin Subdivision's 1 ppb sits at the 42nd percentile in Montana and the 50th nationally (higher means more lead).
Other water systems in Gallatin County
59 other systems share Gallatin County; 23 of them have a higher latest lead result than Hardin Subdivision. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Bozeman City Of | 56,000 | 1.6 ppb |
| Belgrade City Of | 10,460 | 1.79 ppb |
| West Yellowstone Town Of | 9,899 | 1.25 ppb |
| North Star Zoot Water | 4,323 | 3 ppb |
| River Rock County Water And Sewer Dist | 4,200 | 2.81 ppb |
| Rae Water And Sewer Dist 313 | 2,325 | 2.08 ppb |
| Three Forks City Of | 1,900 | 2 ppb |
| Manhattan Town Of | 1,800 | 2 ppb |
| Valley Grove Subdivision | 825 | 2.04 ppb |
| Landmark Subdivision | 750 | 0 (not detected) |
Next steps for Bozeman, MT
Test your own tap with a certified lab first-draw sample; Bozeman, MT 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 Hardin Subdivision 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. Why sampled homes are the worst-case ones is in the guide to reading the number. Systems that went over once often dip back under; here is what that means.