The UC Merced Evaporative Demand Drought Index (EDDI) points to drying over the Colorado River Basin over the next four weeks. EDDI is a new experimental tool that offers potential for tracking quickly emerging drought conditions by analyzing the evaporative demand of the atmosphere. It combines how moist things are with how hot and dry …

Continue reading ‘A dry forecast for the Colorado River Basin. A note on policy implications.’ »

Over the past year, the question of how to account for evaporation and system losses in the Lower Colorado River Basin has become a hot political and policy topic. With the recent Lower Basin water use reduction scheme, we seem to have set the question aside for now. But it’s not going away. My Science …

Continue reading ‘Historical Perspective on the Accounting for Evaporation and System Losses in the Lower Colorado River Basin’ »

By Eric Kuhn and John Fleck On Saturday, April 1st, 1922, at 9:00 AM in Denver’s iconic Brown Palace Hotel, Chairman Herbert Hoover opened the 9th meeting of the Colorado River Commission. The official meeting lasted only 30 minutes. The commission took only one action of consequence. It asked its members to submit to Executive …

Continue reading ‘Carpenter’s Last Stand for Complete State Sovereignty – 100 Years Ago at the Compact Negotiations’ »

Eric Kuhn: One hundred years ago, we had some flexibility because the river was not very well-used. Today, not a drop of the Colorado River reaches the Gulf of California, so we don’t have that luxury. The way I look at it is: we legally allocated water based on an assumption that this river system …

Continue reading ‘Eric Kuhn on less water’ »

By Eric Kuhn and John Fleck The Colorado Commissions’ 8th Meeting Wednesday, March 15th, 1922, Phoenix, Arizona After a six-week break from the disappointing series of negotiating meetings that ended on January 31st  in Washington, D.C., the commissioners from the seven U.S. Colorado River Basin states and the federal government reconvened for the group’s 8th …

Continue reading ‘Getting Acquainted with the Colorado River Basin: 100 years ago in compact negotiations’ »

Our friends at the University of Arizona Press have kindly printed a bunch of new copies of our book Science Be Dammed, this time in paperback so it’s cheaper! Eric and I did a fun Q&A with Abby Mogollon at the press to accompany this second launch: Q: Why did you embark on this project? …

Continue reading ‘Now out in paperback (and perhaps timely given the chaos?): Science Be Dammed – How Ignoring Inconvenient Science Drained the Colorado River’ »

Preparing for climate change on the Colorado River is hard. But we will make it harder, and narrow the scope of our options for dealing with it, if we don’t incorporate realistic flow reduction scenarios in our planning efforts. That’s the thrust of an editorial Brad Udall and I have in this week’s issue of …

Continue reading ‘Taking climate change seriously on the Colorado River: a practical step’ »

The conventional simplification of the Colorado River Compact’s water allocation scheme is that it set aside 7.5 million acre feet of water use for the “exclusive beneficial consumptive use” of the states of the Lower Basin – Nevada, Arizona, and California. In the 21st century, the official accounting shows the Lower Basin states using an …

Continue reading ‘The question of reservoir evaporation – How much water are the Lower Colorado River Basin states really using?’ »