Newcastle, OK
Above the federal action level
Latest 90th-percentile lead: 22.5 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. In the most recent monitoring period, more than 10% of the sampled homes measured above 15 ppb. Use a filter certified to NSF/ANSI 53 for lead for drinking and cooking now, and test your own tap.
Newcastle at a glance
Newcastle serves about 7,900 people through 5,032 service connections, which makes it a medium-sized system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws surface water, in Mcclain County, Oklahoma. EPA system ID: OK2004704; phone on file: 405-387-2690. They can tell you what your service line is made of and whether they pay to replace it.
Newcastle's lead record
That is up 20.1 ppb from 2.4 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Newcastle is 22.5 ppb across 5 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 22.5 ppb over 15 |
| 2025 | 2.4 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. Newcastle's 22.5 ppb sits at the 100th percentile in Oklahoma and the 99th nationally (higher means more lead).
Neighbouring systems
11 other systems share Mcclain County; 0 of them have a higher latest lead result than Newcastle. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Purcell | 6,693 | 0 (not detected) |
| Blanchard | 2,966 | 0 (not detected) |
| Goldsby Water Auth Trust | 2,000 | 0 (not detected) |
| Mcclain Co Rwd # 8 | 1,897 | 6.98 ppb |
| Wayne | 688 | 1.98 ppb |
| Washington | 600 | 4.48 ppb |
| Dibble | 550 | 0 (not detected) |
| Cole | 473 | 0.9 ppb |
| Byars | 275 | 4.87 ppb |
| Mcclain County Rw & Sd #9 | 250 | 0 (not detected) |
Next steps for Newcastle, OK
Use a filter certified to NSF/ANSI 53 for lead on the tap you drink and cook from, now, before you test. Then test your own tap. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Newcastle 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.