Each summer, a number of people in our deserts die of dehydration and heat stroke, unable to find a source of water before being overtaken by death. Access to water has always been a problem in desert regions, one reason why the sources of water in such places as Hueco Tanks have been visited for thousands of years.
One fairly recent development is the use of a plastic sheet and
container as an emergency kit. In a sunny spot, a small pit is dug into the soil on the
floor of an arroyo or other feature that might harbor water too scanty to pool. A cup
is placed on the floor of the pit and the plastic draped over the pit opening and
weighted down on the edges. A pebble is placed in the center of the plastic, insuring
that the plastic dips to a low point over the cup. If all goes well, the heat of the
sun in the "greenhouse" evaporates the soil moisture which condenses on the
underside of the plastic, dripping into the cup.
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.