Jamaica Water Supply, IA
Exceeded the action level in the past
Latest 90th-percentile lead: 4 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. The latest result is under the action level, but this system has gone over 15 ppb before. Lead comes from pipes, not the source water, so a home with a lead service line can still be exposed. Test your own tap.
About Jamaica Water Supply
Jamaica Water Supply serves about 195 people through 125 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 surface water, in Guthrie County, Iowa. EPA system ID: IA3949000; phone on file: 515-201-9147. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Jamaica Water Supply's lead record
That is down 3 ppb from 7 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Jamaica Water Supply is 290 ppb across 12 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 4 ppb |
| 2025 | 7 ppb |
| 2025 | 290 ppb over 15 |
| 2022 | 0 (not detected) |
| 2021 | 4.4 ppb |
| 2020 | 2.3 ppb |
| 2020 | 2.3 ppb |
| 2019 | 2.8 ppb |
| 2019 | 3.8 ppb |
| 2018 | 3 ppb |
| 2018 | 2.7 ppb |
| 2017 | 3.6 ppb |
How Jamaica Water Supply compares
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. Jamaica Water Supply's 4 ppb sits at the 83rd percentile in Iowa and the 87th nationally (higher means more lead).
Neighbouring systems
6 other systems share Guthrie County; 1 of them has a higher latest lead result than Jamaica Water Supply. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Lake Panorama Water Company | 2,900 | 0 (not detected) |
| Guthrie Center Muni Water Work | 1,593 | 4.8 ppb |
| Panora Water Works | 1,142 | 2 ppb |
| Bayard Water Supply | 405 | 0.3 ppb |
| Casey Water Supply | 387 | 1 ppb |
| Yale Water Supply | 267 | 2 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Jamaica, 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 Jamaica 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. Why sampled homes are the worst-case ones is in the guide to reading the number. Why an old exceedance still matters: over the limit before, under it now.