Wyoming Water System, IA
Lead detected, under the action levels
Latest 90th-percentile lead: 2.4 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.
Who runs the water here
Wyoming Water System serves about 523 people through 351 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 Jones County, Iowa. EPA system ID: IA5396039; phone on file: 563-488-3970. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Wyoming Water System's lead record
Against the period ending 2022 (3.2 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Wyoming Water System is 3.2 ppb across 6 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 2.4 ppb |
| 2022 | 3.2 ppb |
| 2021 | 1.3 ppb |
| 2020 | 1.2 ppb |
| 2019 | 1.5 ppb |
| 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. Wyoming Water System's 2.4 ppb sits at the 71st percentile in Iowa and the 77th nationally (higher means more lead).
Neighbouring systems
10 other systems share Jones County; 2 of them have a higher latest lead result than Wyoming Water System. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Anamosa Municipal Water Supply | 4,457 | 1 ppb |
| Monticello Water Supply | 4,040 | 3 ppb |
| Anamosa State Penitentiary | 1,230 | 0 (not detected) |
| Olin Water Supply | 651 | 3.1 ppb |
| Oxford Junction Water Supply | 424 | 0.9 ppb |
| Martelle Water Works | 249 | 0 (not detected) |
| Onslow Water Supply | 201 | 0.6 ppb |
| Center Junction (Eiruss) | 100 | 0 (not detected) |
| Morley Municipal Water Supply | 98 | 0 (not detected) |
| Bacon Addition | 81 | 2 ppb |
Next steps for Wyoming, IA
Test your own tap with a certified lab first-draw sample; Wyoming, 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 Wyoming Water System 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. Size matters more than most people expect: small vs large water systems.