Grayhawk Water, MO
Lead detected, under the action levels
Latest 90th-percentile lead: 1.41 ppb (monitoring period 2022-2024). 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.
Grayhawk Water at a glance
Grayhawk Water serves about 750 people through 314 service connections, which makes it a small system under EPA's size classes. It is privately owned and draws groundwater, in Ste. Genevieve County, Missouri. EPA system ID: MO4010701; phone on file: 573-483-2511. They can tell you what your service line is made of and whether they pay to replace it.
Lead results over time
Against the period ending 2021 (1.82 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Grayhawk Water is 3.83 ppb across 6 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 1.41 ppb |
| 2021 | 1.82 ppb |
| 2021 | 1.82 ppb |
| 2019 | 2.78 ppb |
| 2018 | 2.78 ppb |
| 2016 | 3.83 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. Grayhawk Water's 1.41 ppb sits at the 59th percentile in Missouri and the 63rd nationally (higher means more lead).
Other water systems in Ste. Genevieve County
7 other systems share Ste. Genevieve County; 2 of them have a higher latest lead result than Grayhawk Water. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Ste Genevieve Pws | 4,999 | 0 (not detected) |
| Ste Genevieve County Pwsd 1 Sc | 3,718 | 1.5 ppb |
| Ste Genevieve County Pwsd 1 North | 1,287 | 1.11 ppb |
| Lake Forest Estates | 811 | 1.35 ppb |
| Bloomsdale Pws | 639 | 1.18 ppb |
| Lake Seven Falls Assn Inc | 475 | 1.4 ppb |
| St Mary Pws | 350 | 3.25 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Ste Genevieve, 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 Grayhawk Water 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. What a 90th-percentile result does and does not tell you: how to read a lead result. Systems that went over once often dip back under; here is what that means.