December 28, 2015--University of Colorado scientists say reservoir evaporation a concern (Durango Herald)

 A focus should be placed on measuring and reducing reservoir evaporation in an effort to meet Colorado’s growing water supply demands, according to a study by the University of Colorado Boulder. The report, unveiled on Monday, focused on conservation, a popular theme touted by water managers across Colorado. The conservation push is featured in a statewide plan finalized in November that aims to map the future of water in the state. Supply shortfalls are expected by 2050 or sooner in the state, with results that could lead to agricultural dry-up and fish and wildlife extinction, as well as increased demands and pressure on municipalities. Colorado’s Water Plan calls for achieving 400,000 acre-feet of municipal and industrial water conservation by 2050. The CU Boulder study states that water managers should focus on addressing reservoir evaporation as part of their efforts. “Evaporation of water from open reservoirs in the arid Western U.S. cannot be neglected any more, especially with the possibility of precipitation decreases occurring as a result of a changing climate,” said Associate Professor Katja Friedrich, a faculty member in the Department of Atmospheric and Oceanic Sciences. “We need to try to plan for both short-term needs and to make sure we have enough water over the coming decades.” The state can’t rely on groundwater alone, as the natural rate that water enters an aquifer is low. Groundwater is considered a nonrenewable resource. “While groundwater storage has its advantages, such as lack of evaporation, it also has its challenges, including slow recharge rates and challenges associated with controlling the recharged water, retrieving the water and delivering the water to the customer,” Colorado’s Water Plan states. Climate projections show Colorado warming by an additional 2.5 degrees to 5 degrees by mid-century, with temperatures in summer increasing more than those in winter. Warming temperatures drive evaporation, which could result in an earlier runoff, a longer irrigation season and a decrease in annual stream flow. To view the full article visit the Durango Herald.