Coal Basin Dwua, NM
Exceeded the action level in the past
Latest 90th-percentile lead: 10 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. 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.
About Coal Basin Dwua
Coal Basin Dwua serves about 116 people through 34 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 groundwater, in Mckinley County, New Mexico. EPA system ID: NM3508217; phone on file: 505-870-1951. They can tell you what your service line is made of and whether they pay to replace it.
Every lead result on file
That is up 7 ppb from 3 ppb in the period ending 2024. The highest 90th-percentile result EPA holds for Coal Basin Dwua is 46 ppb across 9 monitoring periods, 3 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 10 ppb |
| 2024 | 3 ppb |
| 2023 | 3 ppb |
| 2023 | 6 ppb |
| 2022 | 46 ppb over 15 |
| 2021 | 46 ppb over 15 |
| 2021 | 46 ppb over 15 |
| 2018 | 4 ppb |
| 2018 | 4 ppb |
Against other New Mexico systems
Of the 504 New Mexico systems with a lead result, the median latest reading is 1.4 ppb; 14 are over 15 ppb right now and 46 have gone over at some point. Coal Basin Dwua's 10 ppb sits at the 94th percentile in New Mexico and the 97th nationally (higher means more lead).
Nearby utilities
14 other systems share Mckinley County; 1 of them has a higher latest lead result than Coal Basin Dwua. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Gallup Water System | 20,880 | 0 (not detected) |
| Gamerco Water & Sanitation | 1,744 | 8.3 ppb |
| Thoreau Water & Sanitation District | 1,173 | 1.2 ppb |
| Ramah Water & Sanitation District | 517 | 1.5 ppb |
| Yah Ta Hey W & Sd | 435 | 1.4 ppb |
| Whispering Cedars Water Association | 425 | 2 ppb |
| White Cliffs Mdwua | 323 | 2 ppb |
| Top Of The World Water Association Corp | 177 | 0 (not detected) |
| Bluewater Lake Mdwca | 135 | 5.3 ppb |
| D & S Trailer Ranch | 109 | 0 (not detected) |
Next steps for Gallup, NM
Test your own tap with a certified lab first-draw sample; Gallup, NM 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 Coal Basin Dwua 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. Why an old exceedance still matters: over the limit before, under it now.