Global change and water availability and quality: Challenges ahead

The US is in the midst of a continental scale, multiyear water resources experiment. What are we doing? We are expanding population at two to three times the national growth rate, particularly where water stress is already great. We are expanding irrigated agriculture from the west to the east, where increased competition for water has urban, agricultural, and environmental interests at odds, and increasingly, in court. This experiment and related challenges will continue and likely intensify as nonclimatic and climatic factors, such as predicted rising temperature and changes in the distribution of precipitation in time and space, continue to develop.