Armstrong Water Supply, IA
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.
About Armstrong Water Supply
Armstrong Water Supply serves about 918 people through 489 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 Emmet County, Iowa. EPA system ID: IA3203066; phone on file: 712-864-3535. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Every lead result on file
Against the period ending 2021 (0 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Armstrong Water Supply is 2 ppb across 7 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 1 ppb |
| 2021 | 0 (not detected) |
| 2020 | 0 (not detected) |
| 2019 | 0 (not detected) |
| 2019 | 2 ppb |
| 2018 | 0 (not detected) |
| 2018 | 0 (not detected) |
Where this result ranks
Of the 1,066 Iowa systems with a lead result, the median latest reading is 1.4 ppb; 4 are over 15 ppb right now and 36 have gone over at some point. Armstrong Water Supply's 1 ppb sits at the 43rd percentile in Iowa and the 53rd nationally (higher means more lead).
Other water systems in Emmet County
6 other systems share Emmet County; 3 of them have a higher latest lead result than Armstrong Water Supply. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Estherville Water Treatment Plant | 5,974 | 2 ppb |
| Ringsted Water Supply | 365 | 3 ppb |
| Wallingford Municipal Waterworks | 170 | 1 ppb |
| Droessler'S Water | 158 | 7.7 ppb |
| Dolliver Muni Water Supply | 65 | 0 (not detected) |
| Oak Shores | 55 | 0 (not detected) |
Your move
Test your own tap with a certified lab first-draw sample; Armstrong, IA 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 Armstrong Water Supply whether it covers that cost before hiring anyone - many utilities now do. Its latest copper 90th percentile is 1400 ppb (copper action level 1,300 ppb).
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. Systems that went over once often dip back under; here is what that means.