SWS 2007 Lecture 11: Lecture 11

• School: University of Florida
• Department: Soil and Water Sciences
• Course: SWS 2007
• Professor: Bonczek, James Lee

Document Summary

But, 80% of worldwide water withdrawals are from surface water. However, surface water is subject to a number of stresses that threaten its abundance, quality, and biological health. Local, on demand availability, drought resistance, good quality. The number of groundwater withdrawal structures more than quadrupled in the last 50 years. Percent of total water use from groundwater sources. Saudi arabia and libya, use 77% of the estimated total water extraction of non- renewable groundwater. Much of new groundwater development here and worldwide is to supply irrigated agriculture. Over exploitation of renewable and non-renewable groundwater, withdrawals exceed recharge creating deficits in the aquifer. 21 million wells, 65% of irrigation water, 85% of drinking water, annual water table declines exceeding 13 feet have been documented in some areas. It is estimated that 60% of groundwater sources will be in critical state of degradation within the next twenty years.