Doon Water Supply, IA
Lead detected, under the action levels
Latest 90th-percentile lead: 4 ppb (monitoring period 2021-2023). 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 Doon Water Supply
Doon Water Supply serves about 619 people through 240 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 Lyon County, Iowa. EPA system ID: IA6015047; phone on file: 712-470-5913. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Lead results over time
That is up 4 ppb from 0 ppb in the period ending 2020. The highest 90th-percentile result EPA holds for Doon Water Supply is 4 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2023 | 4 ppb |
| 2020 | 0 (not detected) |
| 2017 | 0 (not detected) |
Against other Iowa systems
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. Doon Water Supply's 4 ppb sits at the 84th percentile in Iowa and the 87th nationally (higher means more lead).
Nearby utilities
11 other systems share Lyon County; 2 of them have a higher latest lead result than Doon Water Supply. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Rock Rapids Municipal Water Works | 2,611 | 1.5 ppb |
| Lyon-Sioux Rws-Doon | 1,765 | 4 ppb |
| Lyon-Sioux Rws-Big Sioux | 1,530 | 4 ppb |
| Lyon-Sioux Rws-Rock Rapids | 1,187 | 2 ppb |
| George Water Supply | 1,082 | 2 ppb |
| Inwood Water Supply | 928 | 2.1 ppb |
| Larchwood Water Supply | 926 | 2.4 ppb |
| Lyon-Sioux Rws-Boyden | 605 | 5.3 ppb |
| Little Rock Water Supply | 441 | 9.1 ppb |
| Lester Water Supply | 296 | 2.2 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Doon, 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 Doon Water Supply 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. Systems that went over once often dip back under; here is what that means.