Leonards Mhp, MO
Above the new 10 ppb level coming in 2027
Latest 90th-percentile lead: 10.59 ppb (monitoring period 2026-2026). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. Under the current 15 ppb rule this is not an exceedance, but it is above the 10 ppb action level that takes over in Nov 2027. Test your own tap; filter if your result shows lead.
Leonards Mhp at a glance
Leonards Mhp serves about 48 people through 13 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Jefferson County, Missouri. EPA system ID: MO6048100; phone on file: 314-581-7933. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Lead results over time
That is down 187.21 ppb from 197.8 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Leonards Mhp is 197.8 ppb across 9 monitoring periods, 3 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 10.59 ppb over 10 |
| 2025 | 197.8 ppb over 15 |
| 2025 | 56.87 ppb over 15 |
| 2024 | 28.4 ppb over 15 |
| 2022 | 10.8 ppb over 10 |
| 2021 | 10.8 ppb over 10 |
| 2019 | 4.4 ppb |
| 2018 | 4.4 ppb |
| 2016 | 11.4 ppb over 10 |
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. Leonards Mhp's 10.59 ppb sits at the 99th percentile in Missouri and the 97th nationally (higher means more lead).
Nearby utilities
65 other systems share Jefferson County; 1 of them has a higher latest lead result than Leonards Mhp. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Jefferson Co Cons Pwsd C 1 | 37,000 | 0 (not detected) |
| Jefferson County Pwsd 1 | 21,113 | 7.25 ppb |
| Jefferson County Pwsd 3 | 17,000 | 0 (not detected) |
| Jefferson County Pwsd 2 | 16,548 | 0 (not detected) |
| Festus Pws | 13,000 | 0 (not detected) |
| Jefferson County Pwsd 10 | 10,000 | 3.86 ppb |
| Jefferson County Pwsd 5 | 8,000 | 1.13 ppb |
| Jefferson County Pwsd 6 | 7,500 | 2.93 ppb |
| Desoto Pws | 6,400 | 1.46 ppb |
| Jefferson County Pwsd 7 | 6,100 | 1.7 ppb |
Next steps for St. Louis, MO
Test your own tap with a certified lab first-draw sample; St. Louis, 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 Leonards Mhp 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. This system is in the band the 2027 10 ppb rule changes.