Irwin Municipal Supply, IA
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (monitoring period 2022-2024). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. The latest 90th-percentile result was reported as 0 (not detected at the lab's limit). That says the sampled homes were low, not that your home has no lead service line. Check your utility's service line inventory for your address.
Irwin Municipal Supply at a glance
Irwin Municipal Supply serves about 313 people through 177 service connections, which makes it a very small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Shelby County, Iowa. EPA system ID: IA8340099; phone on file: 712-782-3332. They can tell you what your service line is made of and whether they pay to replace it.
Every lead result on file
That is down 2 ppb from 2 ppb in the period ending 2021. The highest 90th-percentile result EPA holds for Irwin Municipal Supply is 2 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 0 (not detected) |
| 2021 | 2 ppb |
| 2018 | 1 ppb |
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. Irwin Municipal Supply's reported as 0 (not detected) sits at the 15th percentile in Iowa and the 19th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Other water systems in Shelby County
7 other systems share Shelby County; 2 of them have a higher latest lead result than Irwin Municipal Supply. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Harlan Municipal Utilities | 5,067 | 1 ppb |
| Shelby Water Supply | 727 | 0 (not detected) |
| Elk Horn Muni Water Works | 631 | 0 (not detected) |
| Earling Water Supply | 397 | 0 (not detected) |
| Defiance Water Department | 250 | 1.8 ppb |
| Panama Water Works | 235 | 0 (not detected) |
| Portsmouth Water Supply | 189 | 0 (not detected) |
Next steps for Irwin, IA
Look up your address in Irwin Municipal Supply's service line inventory. If it says lead, galvanized or unknown, test your tap. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Irwin Municipal 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. A zero today does not rule out a jump later - the rules are tightening in 2027.