Filer Water Works, ID
Lead detected, under the action levels
Latest 90th-percentile lead: 2.77 ppb (monitoring period 2026-2026). 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.
Who runs the water here
Filer Water Works serves about 2,858 people through 975 service connections, which makes it a small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Twin Falls County, Idaho. EPA system ID: ID5420021; phone on file: 208-326-5001. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Every lead result on file
That is up 2.77 ppb from 0 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Filer Water Works is 4 ppb across 11 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 2.77 ppb |
| 2025 | 0 (not detected) |
| 2025 | 3 ppb |
| 2024 | 4 ppb |
| 2024 | 0 (not detected) |
| 2023 | 0 (not detected) |
| 2023 | 3 ppb |
| 2022 | 3 ppb |
| 2022 | 0 (not detected) |
| 2019 | 3 ppb |
| 2016 | 3 ppb |
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. Filer Water Works's 2.77 ppb sits at the 75th percentile in Idaho and the 79th nationally (higher means more lead).
Neighbouring systems
12 other systems share Twin Falls County; 1 of them has a higher latest lead result than Filer Water Works. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Twin Falls City Of | 56,121 | 0 (not detected) |
| Kimberly City Of | 5,359 | 0 (not detected) |
| Buhl City Of | 4,518 | 0 (not detected) |
| Hansen City Of | 1,200 | 0 (not detected) |
| Castleford City Of | 275 | 0 (not detected) |
| Kanaka Rapids Ranch Water System Inc | 240 | 0 (not detected) |
| Hollister City Of | 220 | 1 ppb |
| Rock Ledge Estates | 150 | 0 (not detected) |
| Meander Point Subd | 140 | 0 (not detected) |
| Murtaugh City Of | 130 | 0 (not detected) |
What to do in your house
Test your own tap with a certified lab first-draw sample; Filer, 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 Filer Water Works 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. The action level is dropping - the 10 ppb rule from 2027.