The desert presents an extreme challenge for survival, where water is a profoundly scarce resource. Understanding how to locate and utilize water is fundamental for anyone navigating these arid landscapes.
Natural Ground and Surface Sources
Identifying natural water sources in desert environments often involves observing the landscape and animal behavior. Ephemeral pools, which form after rainfall, can be temporary sources, particularly in depressions or sandy washes. Riverbeds prone to flash flooding can also hold water beneath the surface even when dry. Digging in such locations, especially at the bends of washes, may reveal shallow groundwater.
Oases represent consistent water sources, often indicated by lush vegetation in an otherwise barren expanse. Trees like mesquite and acacia, with deep root systems, can signal underground water. Animal tracks converging towards an area can also lead to hidden water points, as wildlife congregates around these sources. Underground reservoirs, or aquifers, store water between sand grains or within porous rock formations, providing a sustained supply even during prolonged dry periods.
Collecting Atmospheric Moisture
Beyond ground sources, atmospheric moisture offers another avenue for water collection, albeit often in smaller quantities. Dew collection is a straightforward method, particularly effective in areas with cool nights following hot days. An absorbent cloth, such as a t-shirt, can wipe dew from plants or surfaces and then be wrung into a container. Spreading a clean plastic sheet flat on the ground or elevated slightly also allows dew to condense on its surface overnight for morning collection.
Solar stills harness the sun’s energy to extract water from soil or vegetation through condensation. To construct one, dig a pit approximately four feet wide and three feet deep, placing a container in a smaller hole at its center. Cover the pit with a clear plastic sheet, anchored at the edges with rocks, and use a small weight in the center to create a cone shape. This directs condensed vapor into the container, yielding a few hundred milliliters to a liter of water in 24 hours. Rare rainfall can also be captured using tarpaulins, plastic sheets, or rain-soaked clothing wrung into containers.
Water from Desert Plants
Certain desert plants have adapted to store water within their tissues, offering a potential source. Cacti, with thick stems and fleshy pads, are designed for water retention. The saguaro cactus can store hundreds of gallons in its trunk, and prickly pear cacti have water-filled pads. Succulents like agave and aloe vera also possess fleshy leaves that act as water reservoirs.
Extracting water from these plants requires careful handling due to spines. For prickly pear, cut the pads and squish or wring the inner flesh to release liquid. However, consuming water directly from many cacti, such as saguaro or most barrel cacti, is not advisable. Their fluid contains high alkali levels and can induce vomiting, diarrhea, or temporary paralysis. The fishhook barrel cactus is one of the few non-toxic barrel varieties that can provide emergency water, though its liquid is not pure. Avoid plants with milky sap, as this often indicates toxicity.
Making Found Water Safe
Any water acquired in the desert should be treated to ensure it is safe for consumption. Untreated water can harbor various pathogens, including bacteria, viruses, and parasites, leading to illnesses like giardiasis and cryptosporidiosis. These can cause severe symptoms such as chronic diarrhea, abdominal cramps, and nausea.
Boiling water for at least one minute kills most harmful microorganisms. Filtration can remove larger sediments and particles from cloudy water, using layers of cloth, sand, or charcoal. However, filtration alone does not eliminate microscopic pathogens, requiring further purification. Chemical purification tablets, often containing chlorine dioxide, are another option, and ultraviolet light devices can also neutralize pathogens in clear water.