Well Water in Placitas, New Mexico
Sandoval County · Population ~5,000 · Aquifer: Northern Sandia Basin / Various Fractured Rock
Hardness: Moderate to Very Hard (varies significantly)
Placitas sits north of Albuquerque in Sandoval County, at the northern end of the Sandia Basin. Most residents depend on private wells, though some are served by the Placitas Trails Water Cooperative. Water quality here varies enormously — even between neighboring properties — because the fractured rock geology creates highly localized aquifer conditions.
Arsenic: The Primary Concern
Arsenic is the major water quality issue in Placitas, driven by the area's volcanic geology. The Jemez Mountains volcanic complex to the north is the source — rocks in that system can contain several hundred parts per million of arsenic, which leaches into groundwater over geological time.
Arsenic has been detected not only in private wells but even in the Placitas Trails Water Cooperative supply. When even the community system has arsenic detections, private well owners should assume they need to test.
See our comprehensive arsenic guide for health effects, testing, and treatment details.
Aquifer Depletion
Aquifer levels in the Placitas area are reaching what hydrogeologists describe as "dangerously low levels." The northern Sandia Basin has limited recharge — most water entering the aquifer fell as rain or snow decades or centuries ago.
As the aquifer depletes, two things happen: wells go dry, and the water that remains becomes more concentrated with minerals and contaminants. Placitas is experiencing both.
The Variability Problem
One of the most frustrating aspects of Placitas water is how much it varies from well to well. Your neighbor's water can be completely different from yours — different hardness, different arsenic levels, different everything. This is because the fractured rock geology creates isolated pockets of groundwater with very different characteristics.
The practical implication: you cannot rely on your neighbor's test results. Every well needs its own testing.
Common issues beyond arsenic include hardness, iron (rust staining), manganese (black staining), and high total dissolved solids.
What Placitas Residents Should Do
Test comprehensively: arsenic, uranium, fluoride, iron, manganese, hardness, TDS, bacteria, nitrates, pH, and conductivity. Given the arsenic geology, test for arsenic at least once, and retest if your well depth or pump settings change.
Be aware of the seasonal arsenic cycle — winter concentrations can be higher than summer due to reduced pumping allowing deep, high-arsenic water to rise.
For treatment options and local companies familiar with Placitas water, see our resources page.
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 Placitas area, but the only way to know what's in your water is to test it.
Sources
- USGS — Northern Sandia Basin Groundwater Studies
- NM Bureau of Geology — Jemez Mountains Volcanic Arsenic Sources
- Placitas Trails Water Cooperative — Water Quality Reports
- NMED — Private Well Arsenic Monitoring Data