Mercer Pws, MO
Above the new 10 ppb level coming in 2027
Latest 90th-percentile lead: 13.66 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. 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.
About Mercer Pws
Mercer Pws serves about 318 people through 181 service connections, which makes it a very small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Mercer County, Missouri. EPA system ID: MO2010515; phone on file: 660-382-4210. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Lead results over time
That is up 13.66 ppb from 0 ppb in the period ending 2022. The highest 90th-percentile result EPA holds for Mercer Pws is 13.66 ppb across 7 monitoring periods, none of them over 15 ppb (1 over 10 ppb).
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 13.66 ppb over 10 |
| 2022 | 0 (not detected) |
| 2022 | 0 (not detected) |
| 2019 | 0 (not detected) |
| 2019 | 0 (not detected) |
| 2016 | 0 (not detected) |
| 2016 | 0 (not detected) |
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. Mercer Pws's 13.66 ppb sits at the 100th percentile in Missouri and the 98th nationally (higher means more lead).
Neighbouring systems
1 other system shares Mercer County; 0 of them have a higher latest lead result than Mercer Pws. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Princeton Pws | 1,283 | 0 (not detected) |
What to do in your house
Test your own tap with a certified lab first-draw sample; Mercer, 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 Mercer Pws 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. See what changes at 10 ppb in 2027.