Mountain Shadows Hoa Inc., ID
Exceeded the action level in the past
Latest 90th-percentile lead: 4 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.
Mountain Shadows Hoa Inc. at a glance
Mountain Shadows Hoa Inc. serves about 89 people through 81 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Boise County, Idaho. EPA system ID: ID4080100; phone on file: 530-521-4316. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Lead results over time
That is up 2 ppb from 2 ppb in the period ending 2024. The highest 90th-percentile result EPA holds for Mountain Shadows Hoa Inc. is 19 ppb across 12 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 4 ppb |
| 2024 | 2 ppb |
| 2023 | 4 ppb |
| 2022 | 3 ppb |
| 2021 | 3 ppb |
| 2020 | 0 (not detected) |
| 2019 | 0 (not detected) |
| 2019 | 13 ppb over 10 |
| 2018 | 3 ppb |
| 2018 | 3 ppb |
| 2017 | 19 ppb over 15 |
| 2016 | 0 (not detected) |
Against other Idaho systems
Of the 763 Idaho systems with a lead result, the median latest reading is 1 ppb; 3 are over 15 ppb right now and 46 have gone over at some point. Mountain Shadows Hoa Inc.'s 4 ppb sits at the 84th percentile in Idaho and the 87th nationally (higher means more lead).
Nearby utilities
19 other systems share Boise County; 2 of them have a higher latest lead result than Mountain Shadows Hoa Inc.. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Horseshoe Bend Water Supply | 750 | 2 ppb |
| Idaho City Water Dept | 531 | 2 ppb |
| Wilderness Ranch Owners Association Inc | 525 | 4 ppb |
| Terrace Lakes Water Company | 475 | 4 ppb |
| Mountain View Water And Road Assn | 305 | 2 ppb |
| Castle Mountain Creeks Owners Assn | 250 | 1 ppb |
| Duquette Pines Homeowners Association | 163 | 1 ppb |
| Scriver Woods Homeowners Assn | 160 | 0 (not detected) |
| Mores Creek Rim Ranch Water Dist | 140 | 3 ppb |
| Rivers Point Property Owners Assn | 140 | 3 ppb |
Your move
Test your own tap with a certified lab first-draw sample; Garden Valley, ID 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 Mountain Shadows Hoa Inc. 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. The lead result guide covers how utilities pick the homes they sample. Why an old exceedance still matters: over the limit before, under it now.