A subtle wisp of smoke against a clear August sky marked the beginning of a significant wildfire in New Mexico’s Sangre de Cristo Mountains, igniting near the village of Cundiyó and rapidly spreading through drought-parched canyons feeding the Río Frijoles. This vital watershed, alongside the Río en Medio, flows into Santa Cruz Lake, a reservoir that sustains the Santa Cruz River, further augmented by the Río Quemado. For centuries, an intricate network of approximately 30 hand-dug channels, known as acequias, has channeled this water to small family farms across historic communities. Collectively owned and managed by around 3,000 parciantes, or members, these acequias, predating the Santa Cruz Dam by generations, are recognized as distinct political subdivisions of New Mexico, governed by commissions and overseen by dedicated mayordomos responsible for water distribution and infrastructure maintenance.

The Frijoles Fire’s trajectory, with over half of the Río Frijoles watershed directly in its path, immediately placed the health of this delicate ecosystem and the future of its agricultural irrigation at serious risk. Ron Gallegos, chair of the Santa Cruz Irrigation District, which manages water for downstream irrigators, expressed the palpable anxiety: "Once it started, I was just waiting for a call, a text, a message from somebody to see if they could pump water from the lake." His anticipation was soon realized as U.S. Forest Service aircraft began drawing water from Santa Cruz Lake to combat the blaze and deploying fire retardant to curb its spread. Gallegos’ district received a contract for its water use, a modest compensation of one cent per gallon, totaling around $8,500 for approximately 850,000 gallons. Despite the relatively small volume, the imperative to protect the watershed, which supports the livelihoods of some 3,000 people, made the effort feel profoundly worthwhile.

As of early October, with the Frijoles Fire approximately 90% contained nearly two months after its ignition, initial assessments suggested that much of the burn occurred at a low intensity, potentially mitigating long-term environmental damage. However, the specter of post-fire flooding looms large, threatening to increase sediment runoff into Santa Cruz Lake. Local communities are voicing concerns about the potential impact of this sediment and the fire retardant on the water quality they depend upon for agriculture and daily life.

Even before the Frijoles Fire, the region’s irrigation system faced escalating challenges due to the erratic weather patterns characterized by extreme shifts between prolonged drought and intense rainfall in recent years. This year’s severe lack of snowfall and consistently high temperatures drastically reduced natural runoff, leading to critically low water levels. Hydrogeologist and geochemist Steve Finch described the situation as potentially "the worst on record," noting that a nearby U.S. Geological Survey gauge registered a mere 4 cubic feet per second throughout the summer, a stark contrast to the normal flow of 20 to 30 cubic feet per second. These diminished and warmer water levels contributed to an early-season algae bloom, transforming the lake into a murky green expanse with an unpleasant odor.

Joel Esquibel, who operates and maintains the Santa Cruz Dam, a role inherited from his father, meticulously monitors the lake’s water levels. His concern grew as the fire advanced, noting that the water had not been this low since a dredging operation in the late 1980s. Fortunately, by the end of September, the moisture from Hurricane Polo brought a welcome 15-foot rise in the lake’s level.

However, the threat of excessive water also carries significant risks. A historic flood in 2025 devastated acequia infrastructure, causing a complete halt to irrigation as communities painstakingly rebuilt headgates and cleared months’ worth of debris and silt, a process that incurred hundreds of thousands of dollars in costs. The torrential rains in September 2025, which replenished the lake, also carried Frijoles Fire debris and silt into the reservoir. Finch expressed apprehension that this influx will reduce the reservoir’s storage capacity, estimating that Santa Cruz Lake has already accumulated approximately 1,000 acre-feet of silt over the past century, representing about a quarter of its total capacity. The exact amount of silt deposited by the post-fire rains remains undetermined, but Finch anticipates that the reservoir will eventually require further dredging to restore its storage capabilities.

The potential environmental impact of fire retardants used in firefighting efforts also came under scrutiny. On August 4th, the same day the Frijoles Fire began, New Mexico Representative Teresa Leger Fernández, a Democrat, formally requested that the Government Accountability Office investigate the prevalence and potential effects of toxic metals in fire retardants employed by the U.S. Forest Service and the Department of the Interior. While acknowledging the "essential, lifesaving support" of aerial firefighting, the letter, co-signed by eight other members of Congress, highlighted recent reports raising concerns about the safety of commonly used retardants.

In response, U.S. Forest Service spokesperson Claudia Brookshire stated that all fire retardants used by the agency are categorized by the Environmental Protection Agency as "practically non-toxic" to mammals and aquatic species. She emphasized that the Forest Service strictly prohibits retardant drops within waterways and designated avoidance areas for cultural resources or protected species. While fire retardants are primarily composed of two forms of phosphate, widely utilized in fertilizers, independent investigations in California have detected arsenic, cadmium, chromium, and lead in samples collected after several major wildfires.

Further compounding these concerns, independent analysis conducted three years after the massive Hermit’s Peak/Calf Canyon Fire, which scorched over 340,000 acres of northern New Mexico forestland, revealed the presence of heavy metals in private well water. A 2026 report attributed these findings to both naturally occurring ores and the effects of burnt structures and fire suppressants. The Forest Service reported that approximately 453,000 gallons of retardant were deployed on the Frijoles Fire, a significant amount but less than a quarter of the 1,600,000 gallons used on the much larger Hermit’s Peak/Calf Canyon Fire, which spanned approximately 16,000 acres, less than 5% of the size of the Hermit’s Peak blaze.

When questioned at a public meeting in early September about the presence of heavy metals in the retardant used on the Frijoles Fire, Lawrence Lujan, a deputy district ranger for the Santa Fe National Forest, directed inquiries to the manufacturer. Zak Bollenbacher, president of Perimeter Solutions’ Americas Retardants business, the retardant’s manufacturer, clarified via email that no heavy metals are intentionally added to PHOS-CHEK formulations, and any trace amounts are naturally occurring within the raw materials. He added that the phosphate undergoes multiple purification processes to reduce heavy metal levels below fertilizer grade.

PHOS-CHEK, a brand of firefighting foam developed by Monsanto in the late 1960s, has been widely used for decades. While most of its ingredients are disclosed in material safety data sheets, a portion remains proprietary as trade secrets. This opacity prompted a research team from the University of Southern California to investigate the presence of heavy metals in retardants, analyzing data from fires between 2009 and 2021. Their 2024 findings indicated that one product, Phos-Chek LC95W, previously used for ground applications and phased out by the Forest Service in 2024, contained heavy metal levels significantly exceeding EPA drinking water standards. The agency confirmed that a formulation within the same Phos-Chek line, identical in composition but colored red and applied aerially, was used on the Hermit’s Peak/Calf Canyon blaze. Phos-Chek MVP-Fx, another retardant utilized on the Hermit’s Peak fire and, according to Bollenbacher, deployed to help contain the Frijoles Fire, was also employed in recent major California fires. Subsequent analysis by the USC team detected toxic heavy metals in this product. Lead researcher Daniel McCurry noted that the team did not analyze Phos-Chek 259-Fx, another retardant used on the Frijoles Fire, due to a lack of manufacturer-provided samples.

On the ground, the acequia parciantes anxiously await the long-term consequences. The entire lake has taken on a dark, ash-like hue, and concerns regarding water quality persist. With no further water releases scheduled for the remainder of the year, the accumulated debris and silt will have the winter months to settle. This offers a potential reprieve, as the debris is less likely to be distributed into the acequias in the immediate future.