Rutheron Mutual Water Association, NM
Above the federal action level
Latest 90th-percentile lead: 16 ppb (monitoring period 2025-2027). 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.
Who runs the water here
Rutheron Mutual Water Association serves about 239 people through 94 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 Rio Arriba County, New Mexico. EPA system ID: NM3502221; phone on file: 505-241-9904. They can tell you what your service line is made of and whether they pay to replace it.
Rutheron Mutual Water Association's lead record
That is up 11.2 ppb from 4.8 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Rutheron Mutual Water Association is 16 ppb across 9 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2027 | 16 ppb over 15 |
| 2025 | 4.8 ppb |
| 2022 | 2.1 ppb |
| 2021 | 1.9 ppb |
| 2018 | 2.8 ppb |
| 2018 | 11 ppb over 10 |
| 2017 | 2.2 ppb |
| 2017 | 2.8 ppb |
| 2016 | 2.55 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. Rutheron Mutual Water Association's 16 ppb sits at the 97th percentile in New Mexico and the 99th nationally (higher means more lead).
Other water systems in Rio Arriba County
40 other systems share Rio Arriba County; 0 of them have a higher latest lead result than Rutheron Mutual Water Association. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Espanola Water System | 12,012 | 0 (not detected) |
| Chama Water System | 1,573 | 9.1 ppb |
| Agua Sana Wua | 1,514 | 0 (not detected) |
| El Rito Regional Water & Waste Water Asn | 1,200 | 4.1 ppb |
| Greater Chimayo Mdwca | 1,050 | 2.3 ppb |
| Alcalde Mdwca | 927 | 0.56 ppb |
| Chamita Mdwca | 902 | 0 (not detected) |
| Truchas Mdwca | 629 | 3.1 ppb |
| Velarde Mdwca | 543 | 4.1 ppb |
| Dixon Mdwca | 500 | 1.5 ppb |
Next steps for Los Ojos, NM
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 Rutheron Mutual Water Association whether it covers that cost before hiring anyone - many utilities now do. Its latest copper 90th percentile is 2300 ppb (copper action level 1,300 ppb).
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.