Well Water in Los Lunas, New Mexico
Valencia County · Population ~16,000 (Los Lunas); ~77,000 (Valencia County) · Aquifer: Belen Sub-basin
Hardness: 219 PPM (~12.8 gpg) — Hard
Los Lunas and surrounding Valencia County rely entirely on groundwater from the Belen Sub-basin. The public water system has had to install arsenic treatment at all four of its active wells — which tells you something about what private well owners in the same geology are dealing with.
When the Public System Needs Treatment, So Do You
Between 2009 and 2010, the Los Lunas public water system was required to install arsenic treatment at all four active production wells. The same geology that puts arsenic in the public supply puts it in private wells — but private wells don't come with treatment infrastructure.
If you're on a private well in the Los Lunas / Valencia County area, you are drawing from the same Belen Sub-basin aquifer and facing the same arsenic geology. The difference is that nobody is treating your water for you.
Water Quality Issues
Beyond arsenic, Los Lunas and Valencia County wells face:
- Mercury — detected in area groundwater
- E. coli / bacteria — a concern particularly for shallower wells
- Sediment — affects well performance and water clarity
- Hardness — averaging 219 PPM (~12.8 grains per gallon), classified as "hard"
The Belen Sub-basin is an all-groundwater system — there's no surface water treatment plant blending the supply. What the aquifer produces is what you get.
What to Test For
Given the documented arsenic treatment requirements for the public system, every private well in Valencia County should test for arsenic at a minimum. A full panel should include arsenic, bacteria (total coliform and E. coli), nitrates, mercury, hardness, pH, conductivity, and TDS.
See our testing guide for labs and free testing options, and our arsenic guide for what to do if your levels are elevated.
Every well is different. Two wells on the same street can produce completely different water. The data on this page reflects documented conditions in the Los Lunas area, but the only way to know what's in your water is to test it.
Sources
- NMED Drinking Water Bureau — Los Lunas Public Water System Arsenic Compliance
- USGS — Belen Sub-basin Water Quality Data
- Valencia County — Private Well Information