Foss, OK
Exceeded the action level in the past
Latest 90th-percentile lead: reported as 0 (not detected) (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. The latest result is under the action level, but this system has gone over 15 ppb before. Lead comes from pipes, not the source water, so a home with a lead service line can still be exposed. Test your own tap.
Foss at a glance
Foss serves about 127 people through 90 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 surface water, in Washita County, Oklahoma. EPA system ID: OK2007508; phone on file: 580-592-4513. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Foss's lead record
Against the period ending 2025 (0 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Foss is 42.5 ppb across 13 monitoring periods, 2 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 0 (not detected) |
| 2025 | 0 (not detected) |
| 2025 | 16.5 ppb over 15 |
| 2024 | 13.9 ppb over 10 |
| 2023 | 0 (not detected) |
| 2022 | 0 (not detected) |
| 2021 | 0 (not detected) |
| 2021 | 0 (not detected) |
| 2020 | 0 (not detected) |
| 2020 | 0 (not detected) |
| 2019 | 0 (not detected) |
| 2019 | 42.5 ppb over 15 |
| 2016 | 0 (not detected) |
How Foss compares
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. Foss's reported as 0 (not detected) sits at the 5th percentile in Oklahoma and the 11th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Neighbouring systems
9 other systems share Washita County; 3 of them have a higher latest lead result than Foss. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| New Cordell Utility Authority | 2,903 | 0 (not detected) |
| Burns Flat Pws | 2,057 | 0 (not detected) |
| Washita Co Rwd #2 | 1,032 | 3.87 ppb |
| Sentinel Pws | 859 | 0.64 ppb |
| Dill City | 526 | 5.1 ppb |
| Canute | 524 | 0 (not detected) |
| Corn Pwa | 500 | 0 (not detected) |
| Rocky | 202 | 0 (not detected) |
| Bessie | 190 | 0 (not detected) |
What to do in your house
Test your own tap with a certified lab first-draw sample; Foss, 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 Foss 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. More in what a past exceedance means today.