Boone County Pwsd 9, MO
Lead detected, under the action levels
Latest 90th-percentile lead: 3.79 ppb (monitoring period 2024-2026). 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.
Boone County Pwsd 9 at a glance
Boone County Pwsd 9 serves about 15,035 people through 6,412 service connections, which makes it a large system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Boone County, Missouri. EPA system ID: MO3024058; phone on file: 573-474-9521. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Lead results over time
That is up 1.01 ppb from 2.78 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Boone County Pwsd 9 is 7.98 ppb across 8 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 3.79 ppb |
| 2025 | 2.78 ppb |
| 2023 | 2.78 ppb |
| 2022 | 3.48 ppb |
| 2020 | 3.48 ppb |
| 2019 | 7.98 ppb |
| 2017 | 7.98 ppb |
| 2016 | 5 ppb |
How Boone County Pwsd 9 compares
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. Boone County Pwsd 9's 3.79 ppb sits at the 86th percentile in Missouri and the 86th nationally (higher means more lead).
Nearby utilities
11 other systems share Boone County; 1 of them has a higher latest lead result than Boone County Pwsd 9. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| City Of Columbia Utilities | 126,254 | 2.1 ppb |
| University Of Missouri Columbia | 40,000 | 2.01 ppb |
| Boone County Cons Pwsd 1 | 24,700 | 3.48 ppb |
| Boone County Pwsd 4 | 6,455 | 2.49 ppb |
| Ashland Pws | 4,999 | 2.84 ppb |
| Boone County Pwsd 10 | 4,963 | 2.41 ppb |
| Centralia Pws | 4,027 | 1.32 ppb |
| Hallsville Pws | 1,732 | 1.81 ppb |
| Sturgeon Pws | 945 | 1.59 ppb |
| Kuhle H20 | 450 | 0 (not detected) |
What to do in your house
Test your own tap with a certified lab first-draw sample; Columbia, 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 Boone County Pwsd 9 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.