The Colorado River Basin (CRB) supplies water to around 40 million people living in Colorado, New Mexico, Wyoming, Utah, Arizona, California, and Nevada. The Colorado River’s flow has decreased by 20 percent since 2000, due to a 23-year drought, rising temperatures, and desertification. Average temperatures are projected to rise between 3.5 and 9.5 degrees by 2100, which will magnify the 1.2 million acre-feet of water that evaporates annually. Higher temperatures are already decreasing the density of the winter snowpacks that feed the river, which then increases evaporation as the water moves towards lower basin states, creating a vicious cycle. Thus, the shifting climate is forcing the U.S. to consider how drought multiplies threats not only to individual states, but also to national security, including military bases.
The GAO estimates that more than 100 military bases globally are under threat from water scarcity. Drought is exacerbated by higher-than-average temperatures, which increases electricity demands for things like air conditioning and also increases the risk of wildfires, which have already caused damage to military bases and electrical grids. Moreover, higher temperatures hamper training time and operations on bases, which can also impact military readiness down the road. Similarly, drought and water scarcity have other cascading effects that present a series of challenges for the critical training facilities that the military operates in the CRB, from rising energy and food costs to land subsidence.
Military base ecosystems are tethered in important ways to the surrounding social and natural ecosystems to supply their needs and carry out their missions. Drought stresses parts of the U.S. power grid that rely on hydropower and damages infrastructure. Decreasing river flow reduces the output of electricity from dams such as the Glen Canyon and Hoover dams. As these dams approach their dead-pool zones, their contribution of energy to the surrounding community’s electrical grid decreases too. Indeed, military bases rely on civilian electrical grids, which are already regarded as a security risk; however, as relatively cheap hydro-power becomes scarce, the grid typically replaces it with more expensive and emission-intensive natural gas alternatives.
Similar to electrical grids, military bases source dairy and produce regionally through subsistence supply chains. In the southwest, the water needed to support these industries is becoming scarcer. Drought and warming temperatures may reduce the alfalfa hay acreage used to feed cows, which drives up consumer prices and, over time, can increase the price of certain goods supplied to bases. While small when compared to the military’s massive budget, this could compound the estimated millions of dollars wasted on food for dining services at bases.
Moreover, companies such as Stern Produce, which supplies bases across Arizona, contract local farms that compete for water with large-scale agricultural companies in the region. For example, Fondomonte, a subsidiary of the Saudi Arabian dairy company Almarai, grows alfalfa to feed dairy cows halfway across the world. Agriculture is responsible for close to 80 percent of the water syphoned off from the Colorado River, and as the river dwindles, it becomes harder for surrounding communities to meet increasing demand.
Farms and cities are turning to their groundwater supplies, but heavy reliance on groundwater has its own repercussions. Depleted aquifers cause land subsidence, or sunken earth, that can cause cracks and fissures. Subsidence can disrupt surrounding agricultural land and damage infrastructure, and has already cracked roads and disrupted utility lines. Furthermore, there is major subsidence around Luke Air Force Base in Arizona, called the West Valley Feature. On top of this, lower groundwater tables increase the concentration of chemicals that seep into the ground. Research has identified that much of the soil and water surrounding military bases is contaminated with per- and polyfluorinated substances (PFAS). PFAS are spread in several ways, but on military bases, they are most commonly spread through the use of firefighting foam. These chemicals are particularly dangerous in higher concentrations, without proper treatment. Although, fortunately, this widespread issue has received national attention through President Biden’s plan to combat PFAS pollution, which also reduces the costs of treatment.
The reliance of military bases on civilian power grids, vulnerable subsistence supply chains, and increasingly scarce water resources makes them more vulnerable to drought. While it is difficult to know the exact costs of drought on these bases because evaluation of military infrastructure’s water security risk has only recently been established, to “build enduring advantages,” planning for the far-reaching implications that events such as drought have on military bases is necessary.