Delta Water Supply, IA
Lead detected, under the action levels
Latest 90th-percentile lead: 3.4 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
Delta Water Supply serves about 264 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 groundwater, in Keokuk County, Iowa. EPA system ID: IA5417026; phone on file: 641-660-3667. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Delta Water Supply's lead record
That is up 3.4 ppb from 0 ppb in the period ending 2022. The highest 90th-percentile result EPA holds for Delta Water Supply is 3.4 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 3.4 ppb |
| 2022 | 0 (not detected) |
| 2019 | 0 (not detected) |
| 2016 | 2.6 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. Delta Water Supply's 3.4 ppb sits at the 78th percentile in Iowa and the 85th nationally (higher means more lead).
Neighbouring systems
9 other systems share Keokuk County; 1 of them has a higher latest lead result than Delta Water Supply. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Sigourney Muni Water Works | 2,004 | 1.84 ppb |
| Keota Water Dept | 897 | 0 (not detected) |
| Hedrick Water Supply | 728 | 0 (not detected) |
| What Cheer Water Supply | 646 | 2.1 ppb |
| Richland Water Supply | 542 | 2 ppb |
| Keswick Water System | 252 | 6 ppb |
| South English Water Supply | 238 | 1 ppb |
| Harper Water Supply | 118 | 0 (not detected) |
| Webster Municipal Water Works | 96 | 2 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Sigourney, 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 Delta 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. Why sampled homes are the worst-case ones is in the guide to reading the number. The action level is dropping - the 10 ppb rule from 2027.