A Pulse for Science

Karl Flessa, Professor of Geosciences at the University of Arizona and Co-Chief of the Science Team for the Colorado River Delta Pulse Flow, gets very animated about this natural experiment. “It doesn’t take much to get me started on my favorite topic,” he said to Dos Aguas. His excitement has a solid basis: after decades of studying the decline of this once vibrant delta through its remains, the large Pulse experiment is designed to see if part of it can be rejuvenated – to learn what happens to the land, vegetation and animals when adding a one-time pulse of water. For eight weeks in 2014 the Colorado Delta Pulse Flow project released 107,000 acre feet of water into the dry channel of the Colorado River – a few drops of “back to the future.” Now we have the first report of the results. More…

Colorado Delta Diary

In the 20th century human beings managed to divert and assign ownership to every single drop of water in the Colorado River, leaving nothing for the riverbed and its surrounding delta below Yuma, Arizona. Since 1965 the only flow into these last one hundred miles of the river has been water no one wanted: spring floods too voluminous for the irrigation or diversion canals, groundwater below irrigated fields too salty for good crop growth, urban sewage too contaminated for reuse. Now in the 21st century there are efforts to find new sources of water to rejuvenate some of the Colorado Delta’s former abundance. More…