Big Mountain Water Company, MT
Exceeded the action level in the past
Latest 90th-percentile lead: 7 ppb (monitoring period 2025-2025). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. The latest result is under the action level, but this system has gone over 15 ppb before. Lead comes from pipes, not the source water, so a home with a lead service line can still be exposed. Test your own tap.
Big Mountain Water Company at a glance
Big Mountain Water Company serves about 2,435 people through 384 service connections, which makes it a small system under EPA's size classes. It is privately owned and draws groundwater, in Flathead County, Montana. EPA system ID: MT0000060; phone on file: 406-862-2905. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Big Mountain Water Company's lead record
That is down 3 ppb from 10 ppb in the period ending 2024. The highest 90th-percentile result EPA holds for Big Mountain Water Company is 56 ppb across 7 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 7 ppb |
| 2024 | 10 ppb |
| 2023 | 4 ppb |
| 2023 | 4 ppb |
| 2022 | 56 ppb over 15 |
| 2019 | 1 ppb |
| 2016 | 3 ppb |
Where this result ranks
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. Big Mountain Water Company's 7 ppb sits at the 96th percentile in Montana and the 95th nationally (higher means more lead).
Neighbouring systems
135 other systems share Flathead County; 8 of them have a higher latest lead result than Big Mountain Water Company. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Kalispell Public Works | 25,000 | 2 ppb |
| Whitefish City Of | 10,418 | 2 ppb |
| Flathead County Water And Sewer | 9,520 | 1 ppb |
| Bigfork County Water And Sewer | 6,100 | 2 ppb |
| Columbia Falls City Of | 4,450 | 4 ppb |
| Lakeside Water System | 1,225 | 3 ppb |
| Hungry Horse Co Water And Sewer District | 1,135 | 0 (not detected) |
| Meadow Lake Co Water And Sewer District | 950 | 0 (not detected) |
| Somers Co Water And Sewer Dist | 765 | 2 ppb |
| Ptarmigan Village Inc | 600 | 10 ppb |
Next steps for Whitefish, MT
Test your own tap with a certified lab first-draw sample; Whitefish, 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 Big Mountain Water Company 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. More in what a past exceedance means today.