Delaware Co Rwd #10, OK
Lead detected, under the action levels
Latest 90th-percentile lead: 1.2 ppb (monitoring period 2025-2027). 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.
Who runs the water here
Delaware Co Rwd #10 serves about 1,295 people through 589 service connections, which makes it a small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Delaware County, Oklahoma. EPA system ID: OK6002158; phone on file: 918-791-9100. 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 down 3.7 ppb from 4.9 ppb in the period ending 2024. The highest 90th-percentile result EPA holds for Delaware Co Rwd #10 is 4.9 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2027 | 1.2 ppb |
| 2024 | 4.9 ppb |
| 2021 | 0 (not detected) |
| 2018 | 0 (not detected) |
Against other Oklahoma systems
Of the 870 Oklahoma systems with a lead result, the median latest reading is 0.81 ppb; 6 are over 15 ppb right now and 66 have gone over at some point. Delaware Co Rwd #10's 1.2 ppb sits at the 58th percentile in Oklahoma and the 59th nationally (higher means more lead).
Nearby utilities
25 other systems share Delaware County; 8 of them have a higher latest lead result than Delaware Co Rwd #10. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Grove Municipal Services Auth. | 7,311 | 9.3 ppb |
| Grand Lake Pwa | 2,800 | 3.1 ppb |
| Jay | 2,482 | 0 (not detected) |
| Ketchum Pwa Delaware Co System | 1,805 | 2.3 ppb |
| South Delaware Co Regional Water Auth. | 1,500 | 1.8 ppb |
| West Siloam Springs | 877 | 1.4 ppb |
| Colcord Pwa | 819 | 0 (not detected) |
| Kansas Public Works Authority | 802 | 0 (not detected) |
| Delaware Co Rwd # 12 | 785 | 0 (not detected) |
| Delaware Co Rwsg&Swm District 11 | 750 | 2.5 ppb |
Next steps for Afton, OK
Test your own tap with a certified lab first-draw sample; Afton, OK 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 Delaware Co Rwd #10 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. Size matters more than most people expect: small vs large water systems.