De Soto Water Supply, IA
Lead detected, under the action levels
Latest 90th-percentile lead: 0.5 ppb (monitoring period 2025-2025). 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.
De Soto Water Supply at a glance
De Soto Water Supply serves about 960 people through 445 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 Dallas County, Iowa. EPA system ID: IA2529035; phone on file: 515-834-2233. They can tell you what your service line is made of and whether they pay to replace it.
De Soto Water Supply's lead record
Against the period ending 2023 (0 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for De Soto Water Supply is 4.5 ppb across 5 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 0.5 ppb |
| 2023 | 0 (not detected) |
| 2022 | 2.1 ppb |
| 2021 | 2.8 ppb |
| 2018 | 4.5 ppb |
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. De Soto Water Supply's 0.5 ppb sits at the 33rd percentile in Iowa and the 43rd nationally (higher means more lead).
Neighbouring systems
18 other systems share Dallas County; 6 of them have a higher latest lead result than De Soto Water Supply. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Waukee Water Supply | 31,823 | 0 (not detected) |
| Xenia Rwd (Des Moines) | 12,860 | 1.74 ppb |
| Perry Municipal Water Works | 7,836 | 1 ppb |
| Adel Municipal Water Works | 6,461 | 0 (not detected) |
| Xenia Rwd (Woodward) | 3,465 | 0.7 ppb |
| Dallas Center Water Supply | 1,901 | 0 (not detected) |
| Granger Muni Water Supply | 1,654 | 0 (not detected) |
| Woodward Water Supply | 1,346 | 4 ppb |
| Van Meter Municipal Water Work | 1,074 | 0 (not detected) |
| Midwest Country Estates | 820 | 0 (not detected) |
Next steps for Adel, IA
Test your own tap with a certified lab first-draw sample; Adel, 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 De Soto 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. 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.