Slide 4 of 13
Notes:
The period of 1980-90, though, saw reduced pumping rates. Fuel prices shot up in the late 70s and farmers realized that they did not need as much water as they thought to make high profit margins. New technologies also developed such as the LEPA sprinkler (meaning low-energy proficient application) which uses large drops of water that reduce evaporation loss when compared to center pivot sprinklers. In general, there has also been a better awareness of the problem since 1980.
The exact of effect of these changes is unclear. One study showed a system level rise of 0.8 ft. while another showed an average decline of 1 ft. during this period. The changes have certainly helped, but many declines still occurred, particularly in Texas where some areas showed declines of greater than 15 ft.
