Water Quality · New Mexico
Best Water Quality Counties in New Mexico 2026
Ranked by EPA drinking water health violations.
Top 10 — Water Quality in New Mexico
Score reflects water quality only — not overall county quality.
All New Mexico Counties — Water Quality Rankings
32 counties ranked by water quality score. Overall Score shown for context.
| # | County | Water Quality Score | Overall Score |
|---|---|---|---|
| 1 | De Baca County, NM | 86 | 58.6 |
| 2 | Los Alamos County, NM | 86 | 68.5 |
| 3 | Chaves County, NM | 58.1 | 36.1 |
| 4 | Bernalillo County, NM | 43.4 | 27.6 |
| 5 | Curry County, NM | 41.1 | 33.5 |
| 6 | Eddy County, NM | 36.6 | 36 |
| 7 | Quay County, NM | 31.3 | 53.3 |
| 8 | Roosevelt County, NM | 24.8 | 41.9 |
| 9 | San Juan County, NM | 24.3 | 33.2 |
| 10 | Luna County, NM | 23.9 | 59 |
| 11 | Lea County, NM | 23 | 36.1 |
| 12 | Santa Fe County, NM | 22.7 | 35.3 |
| 13 | Lincoln County, NM | 20.2 | 58.3 |
| 14 | Harding County, NM | 20 | 71.2 |
| 15 | Sandoval County, NM | 18.1 | 50.1 |
| 16 | Grant County, NM | 17.9 | 61.5 |
| 17 | Otero County, NM | 15.8 | 44.4 |
| 18 | Valencia County, NM | 14.2 | 31.9 |
| 19 | McKinley County, NM | 13.3 | 29.2 |
| 20 | Socorro County, NM | 12.2 | 54.4 |
| 21 | Cibola County, NM | 12.1 | 52.9 |
| 22 | Taos County, NM | 10.1 | 48.2 |
| 23 | Sierra County, NM | 7.4 | 53.1 |
| 24 | Union County, NM | 7 | 60.8 |
| 25 | Guadalupe County, NM | 5.3 | 60.1 |
| 26 | Rio Arriba County, NM | 4.4 | 60.6 |
| 27 | San Miguel County, NM | 4 | 45.9 |
| 28 | Torrance County, NM | 3.3 | 42.1 |
| 29 | Mora County, NM | 2.5 | 63.5 |
| 30 | Colfax County, NM | 2 | 54.4 |
| 31 | Hidalgo County, NM | 1.9 | 54.1 |
| 32 | Catron County, NM | 1.1 | 64 |