Twelve Oaks Water System, MO
Lead detected, under the action levels
Latest 90th-percentile lead: 0.4 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.
Twelve Oaks Water System at a glance
Twelve Oaks Water System serves about 314 people through 119 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Lafayette County, Missouri. EPA system ID: MS0360069; phone on file: 314-736-4743. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Every lead result on file
Against the period ending 2022 (0.3 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Twelve Oaks Water System is 0.5 ppb across 7 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 0.4 ppb |
| 2022 | 0.3 ppb |
| 2019 | 0 (not detected) |
| 2018 | 0 (not detected) |
| 2017 | 0 (not detected) |
| 2016 | 0.5 ppb |
| 2016 | 0.4 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. Twelve Oaks Water System's 0.4 ppb sits at the 40th percentile in Missouri and the 42nd nationally (higher means more lead).
Nearby utilities
13 other systems share Lafayette County; 4 of them have a higher latest lead result than Twelve Oaks Water System. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Lafayette County Pwsd 1 | 8,250 | 0 (not detected) |
| Odessa Pws | 5,202 | 3.33 ppb |
| Higginsville Pws | 4,800 | 0 (not detected) |
| Lexington Pws | 4,729 | 2.02 ppb |
| Concordia Pws | 2,500 | 0 (not detected) |
| Wellsgate | 1,447 | 0 (not detected) |
| Waverly Pws | 900 | 4.73 ppb |
| Wellington Pws | 812 | 0 (not detected) |
| Alma Pws | 500 | 0 (not detected) |
| Lake Lafayette Pws | 327 | 0 (not detected) |
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 Twelve Oaks Water System 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. Systems that went over once often dip back under; here is what that means.