Well Water in Pinetop-Lakeside / Show Low, Arizona

Navajo County · Population ~15,000 · Aquifer: C Aquifer (Coconino) / Local Volcanics

Hardness: Moderate

The C Aquifer

The C Aquifer (named for the Coconino Sandstone, its primary formation) is a massive regional aquifer system underlying much of northeastern Arizona. It extends roughly from Flagstaff east to the New Mexico border and from the Mogollon Rim north to the Little Colorado River drainage.

The aquifer is primarily in Permian-age sandstones (Coconino and Supai) and is generally reliable, though yields vary by location. The C Aquifer supplies most of the drinking water for communities along the Mogollon Rim and in the White Mountains.

Water quality is generally good, but natural arsenic and fluoride occur at varying levels depending on local geology and depth.

Wildfire and Watershed Impact

The White Mountains have experienced catastrophic wildfires:

• Rodeo-Chedeski Fire (2002) — 468,638 acres burned, the largest Arizona wildfire at the time
• Wallow Fire (2011) — 538,049 acres, surpassing Rodeo-Chedeski as Arizona's largest

Severe wildfire fundamentally changes watershed behavior. Burned soil becomes hydrophobic (water-repellent), increasing runoff and reducing infiltration that would otherwise recharge groundwater. Ash and debris mobilize into waterways, carrying contaminants including heavy metals, nutrients, and polycyclic aromatic hydrocarbons (PAHs).

The long-term effects on groundwater recharge and quality in fire-affected watersheds are still being studied. But the pattern is clear: less water infiltrates to recharge the aquifer, and what does infiltrate may carry fire-derived contaminants.

Water Supply Challenges

Despite being in Arizona's "mountain country," the White Mountains communities face real water supply limitations. The C Aquifer is large but not unlimited, and population growth in the Pinetop-Lakeside and Show Low corridor is steady.

These communities have no CAP allocation — they depend on local groundwater and limited surface water. Conservation measures and careful well management are essential for long-term sustainability.

Testing Recommendations

White Mountains well owners should test for:

• Arsenic and fluoride — naturally occurring in the C Aquifer system
• Bacteria and nitrate — annual basics
• Hardness, TDS, pH — baseline mineral panel

If your well is in an area affected by wildfire, consider testing for heavy metals and turbidity, particularly after heavy rain events that mobilize burned-area runoff. See our testing guide for certified labs.