Grinell Estates Hoa, 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.
Who runs the water here
Grinell Estates Hoa serves about 48 people through 20 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Missoula County, Montana. EPA system ID: MT0003261; phone on file: 406-626-5698. 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 2019 (0 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Grinell Estates Hoa is 2 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 1 ppb |
| 2019 | 0 (not detected) |
| 2016 | 2 ppb |
How Grinell Estates Hoa 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. Grinell Estates Hoa's 1 ppb sits at the 44th percentile in Montana and the 50th nationally (higher means more lead).
Other water systems in Missoula County
80 other systems share Missoula County; 23 of them have a higher latest lead result than Grinell Estates Hoa. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Missoula Water | 68,200 | 2 ppb |
| Lolo Water And Sewer Dist | 3,315 | 2 ppb |
| Seeley Lake Water District | 1,575 | 4 ppb |
| El Mar Estates Msla Co Water | 1,350 | 1 ppb |
| Westview Mobile Home Park | 947 | 1 ppb |
| Phantom Hills Water System | 810 | 3 ppb |
| Travois Village Mobile Park | 702 | 2 ppb |
| Wye Area Water System | 512 | 1 ppb |
| Grant Creek Water Users Association Inc | 380 | 0 (not detected) |
| Katoonah Lodges | 258 | 3 ppb |
Your move
Test your own tap with a certified lab first-draw sample; Frenchtown, 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 Grinell Estates Hoa 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.