The U.S. Geological Survey collected water-level, spring-flow, and power-consumption data in the Devils Hole area from July 1973 through June 1974. The work for this second annual data report was financed by the National Park Service. The work for the first annual, report (Larson, 1974) was financed jointly by the U.S. Bureau of Sport Fisheries and the U.S. Geological Survey.
Continuous recorders were used to monitor water levels in Devils Hole, two observation wells, and the flow from four springs. Also, monthly readings were made on two wells to help define a general trend of ground-water levels. Also, monthly meter readings of six electrically powered irrigation wells provided a record of power consumption, which in turn is a measure of the amount of water pumped.
The purpose of the work is to observe the effects of groundwater withdrawals for irrigation on the level in Devils Hole and the flow from the major springs in the area. The pool in Devis Hole, which is a collapsed fault structure, is the only known native habitat of desert pupfish, Cyprinodon diabolis.
