Aztec Domestic Water System, NM
Lead detected, under the action levels
Latest 90th-percentile lead: 0.7 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.
About Aztec Domestic Water System
Aztec Domestic Water System serves about 9,673 people through 3,246 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 San Juan County, New Mexico. EPA system ID: NM3509824; phone on file: 505-334-7611. They can tell you what your service line is made of and whether they pay to replace it.
Every lead result on file
Against the period ending 2025 (1.1 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Aztec Domestic Water System is 3.6 ppb across 5 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 0.7 ppb |
| 2025 | 1.1 ppb |
| 2022 | 1.3 ppb |
| 2019 | 1.9 ppb |
| 2016 | 3.6 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. Aztec Domestic Water System's 0.7 ppb sits at the 32nd percentile in New Mexico and the 47th nationally (higher means more lead).
Nearby utilities
13 other systems share San Juan County; 6 of them have a higher latest lead result than Aztec Domestic Water System. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Farmington Water System | 47,655 | 2.2 ppb |
| Bloomfield Water Supply System | 9,536 | 2 ppb |
| Lee Hammond Water | 8,817 | 0.83 ppb |
| Lower Valley Water Users Association | 8,683 | 0.5 ppb |
| Morningstar Water System | 5,694 | 0.55 ppb |
| Northstar Mdwca | 3,784 | 0 (not detected) |
| Flora Vista Mutual Domestic | 3,726 | 0 (not detected) |
| Upper La Plata Water Users Association | 2,265 | 0.6 ppb |
| Southside Mutual Domestic Water | 1,609 | 5 ppb |
| Blanco Mdwca | 1,148 | 0.69 ppb |
Next steps for Aztec, NM
Test your own tap with a certified lab first-draw sample; Aztec, 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 Aztec Domestic Water System 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. What a 90th-percentile result does and does not tell you: how to read a lead result. The action level is dropping - the 10 ppb rule from 2027.