Mo American Mexico, MO
Lead detected, under the action levels
Latest 90th-percentile lead: 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.
Mo American Mexico at a glance
Mo American Mexico serves about 13,000 people through 4,999 service connections, which makes it a large system under EPA's size classes. It is privately owned and draws groundwater, in Audrain County, Missouri. EPA system ID: MO2010519; phone on file: 636-263-7370. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Lead results over time
Against the period ending 2022 (0 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Mo American Mexico is 2 ppb across 7 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 1 ppb |
| 2022 | 0 (not detected) |
| 2022 | 0 (not detected) |
| 2019 | 0 (not detected) |
| 2019 | 0 (not detected) |
| 2016 | 2 ppb |
| 2016 | 2 ppb |
Where this result ranks
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. Mo American Mexico's 1 ppb sits at the 49th percentile in Missouri and the 55th nationally (higher means more lead).
Other water systems in Audrain County
5 other systems share Audrain County; 3 of them have a higher latest lead result than Mo American Mexico. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Audrain County Consolidated Pwsd 2 | 4,062 | 1.76 ppb |
| Vandalia Pws | 3,140 | 0 (not detected) |
| Martinsburg Pws | 559 | 1.6 ppb |
| Laddonia Pws | 511 | 0 (not detected) |
| Farber Pws | 450 | 3.8 ppb |
Next steps for Cottleville, MO
Test your own tap with a certified lab first-draw sample; Cottleville, 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 Mo American Mexico 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.