Delaware Co Rwsg&Swm District 11, OK
Lead detected, under the action levels
Latest 90th-percentile lead: 2.5 ppb (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. 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.
Delaware Co Rwsg&Swm District 11 at a glance
Delaware Co Rwsg&Swm District 11 serves about 750 people through 373 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 surface water, in Delaware County, Oklahoma. EPA system ID: OK3002157; phone on file: 918-868-2277. They can tell you what your service line is made of and whether they pay to replace it.
Delaware Co Rwsg&Swm District 11's lead record
That is up 2.5 ppb from 0 ppb in the period ending 2022. The highest 90th-percentile result EPA holds for Delaware Co Rwsg&Swm District 11 is 2.5 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 2.5 ppb |
| 2022 | 0 (not detected) |
| 2019 | 0 (not detected) |
| 2016 | 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 Rwsg&Swm District 11's 2.5 ppb sits at the 80th percentile in Oklahoma and the 77th nationally (higher means more lead).
Other water systems in Delaware County
25 other systems share Delaware County; 4 of them have a higher latest lead result than Delaware Co Rwsg&Swm District 11. 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 |
| Delaware Co Rwd #10 | 1,295 | 1.2 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) |
Your move
Test your own tap with a certified lab first-draw sample; Twin Oaks, 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 Rwsg&Swm District 11 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. Size matters more than most people expect: small vs large water systems.