Oakland Water Works, MO
Lead detected, under the action levels
Latest 90th-percentile lead: 3.1 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.
About Oakland Water Works
Oakland Water Works serves about 750 people through 284 service connections, which makes it a small system under EPA's size classes. It is privately owned and draws groundwater, in Adams County, Missouri. EPA system ID: MS0010007; phone on file: 314-736-4743. 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 3 ppb from 6.1 ppb in the period ending 2022. The highest 90th-percentile result EPA holds for Oakland Water Works is 6.1 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 3.1 ppb |
| 2022 | 6.1 ppb |
| 2019 | 2.6 ppb |
| 2017 | 4.1 ppb |
Against other Missouri systems
Of the 1,674 Missouri systems with a lead result, the median latest reading is 1.04 ppb; 2 are over 15 ppb right now and 74 have gone over at some point. Oakland Water Works's 3.1 ppb sits at the 83rd percentile in Missouri and the 83rd nationally (higher means more lead).
Next steps for Des Peres, MO
Test your own tap with a certified lab first-draw sample; Des Peres, MO 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 Oakland Water Works 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.