Rockport Colony, MT
Lead detected, under the action levels
Latest 90th-percentile lead: 2 ppb (monitoring period 2024-2026). 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.
Rockport Colony at a glance
Rockport Colony serves about 92 people through 10 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Teton County, Montana. EPA system ID: MT0001778; phone on file: 406-469-2247. They can tell you what your service line is made of and whether they pay to replace it.
Every lead result on file
That is up 2 ppb from 0 ppb in the period ending 2019. The highest 90th-percentile result EPA holds for Rockport Colony is 2 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 2 ppb |
| 2019 | 0 (not detected) |
| 2017 | 0 (not detected) |
Against other Montana systems
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. Rockport Colony's 2 ppb sits at the 67th percentile in Montana and the 70th nationally (higher means more lead).
Other water systems in Teton County
8 other systems share Teton County; 4 of them have a higher latest lead result than Rockport Colony. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Choteau City Of | 1,691 | 4 ppb |
| Fairfield Town Of | 718 | 1 ppb |
| Tri County Water District | 470 | 1 ppb |
| Dutton Town Of | 338 | 27 ppb |
| Power Teton County Water Dist | 205 | 5 ppb |
| New Rockport Colony Inc | 160 | 0 (not detected) |
| Bynum - Teton Co W & S District | 100 | 3 ppb |
| Miller Colony | 84 | 1 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Pendroy, 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 Rockport Colony 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. The action level is dropping - the 10 ppb rule from 2027.