New Mexico Must Become a Catcher of Rain

This op-ed by Justin Zorn, author and Senior Adviser for the Center for Economic and Policy Research, and Erin English, Senior Engineer and Practice Leader at Biohabitats, originally appeared in the Santa Fe New Mexican on July 7th, 2024. It is republished here with permission.

Residents of Las Vegas, N.M., are facing a nightmarish contradiction: massive flooding from rainfall and an unprecedented water shortage that triggered the shutdown of nonessential businesses, crippling the local economy and forcing and the cancellation of Fourth of July fiestas. Over the past week, there’s been water everywhere — but hardly a drop to drink.

While the extreme situation in Las Vegas is due to a “cascading event” caused by lingering scars of the 2022 Hermits Peak/Calf Canyon Fire, it illustrates a broader reality that all of us New Mexicans face. In an age of megadroughts, dangerous decimation of groundwater and wildfires in our watersheds, we need to improve our ability to harness and decentralize water. We should invest in the capacity to collect and store far more of what falls from the sky.

The peoples of our region have been harvesting rainwater since ancient times. Today, the essential technology is straightforward: Collect rainwater from rooftops — on homes, warehouses, factories — and send it down gutters into tanks, where it can be filtered and used for domestic purposes, commercial uses, landscaping or industrial processes.

Yet recent research shows why rainwater harvesting — at scale — could be a key solution to the water crisis. Collecting even a small fraction of a percent of rainwater in an area can buffer water shortages for household uses while simultaneously recharging groundwater. It can contribute vital redundancy for communities like Las Vegas where centralized water supplies are increasingly at risk from catastrophic forest fire, drought and shortages.

The strategy can help reduce stormwater runoff and avoid the carbon emission associated with pumping water through utility lines. The advent of technologies including UV-based filtration make it possible to use harvested rainwater for purposes beyond just toilets or outdoor irrigation.

Rainwater is having a moment. Companies including Apple, Ford and Toyota have recently built major facilities that feature rainwater harvesting. Cities including Tucson, Ariz., and Austin, Texas, have touted their incentives for homes and businesses or their investment in municipal infrastructure. “Living Buildings” are becoming net zero water by harvesting 100% of their water needs from rain.

Large underground rainwater harvesting cisterns were installed as a retrofit to the Domenici Federal Courthouse in Albuquerque, NM to harvest rooftop runoff for irrigation at this SITES(R) certified pilot project.

For decades, Santa Fe has been a leader in reducing water usage. The city has reduced per capita average use by nearly 50% since 1995. Santa Fe offers rebates for the purchase of rainwater-harvesting equipment — an important policy. But we can go much further.

An estimated 5 billion gallons of rainwater fall upon the city of Santa Fe in the average year. Collecting and storing just a tiny portion of this amount could radically change our relationship with water and carry forward our leadership with water innovation in the Southwest.

Santa Fe’s city government should take first steps that could lead the way for other municipalities like Las Vegas as well as the state government. City facilities — especially new construction and the largest buildings — should be equipped with rainwater harvesting systems. While this involves some upfront investment and training for operators, installations will pay for themselves in time given current water rates.

The city should work with private developers to employ more impactful incentives for rainwater harvesting. The redevelopment of the midtown campus is a prime opportunity to combine economic investments with ecological enrichment. Working to install rainwater collection systems across the campus could create a high desert oasis and water hub — a hot spot for both business and biodiversity.

Santa Fe should work with state government to create new means for financing rainwater harvesting — particularly for large industrial or agricultural users. Because a 50,000-square-foot roof can generally collect up to 31,000 gallons of water from a single inch of rain, the owners of major warehouses and other large facilities can harness economies of scale. Data centers, such as Meta’s Los Lunas facility, consume huge amounts of water for cooling and could especially benefit from large-scale rainwater collection.

Even in an era of scarce and unpredictable precipitation, and with watersheds increasingly impacted by wildfire, New Mexico can increase its water security — and perhaps even enable abundance. Rainwater harvesting is an ancient and straightforward technology. But, often, the best solutions are the simplest.