For more than a century of development, Colorado River governance has lived under a
tension between individual communities’ desires to use more water and the collective
need to balance basin-scale supply and use for the benefit of the region as a whole.
Incentives favoring individual communities at the expense of the collective good have
brought us to the edge of the current crisis.
The latest project from our little Colorado River working group takes a deep dive into the arcane rules governing what Arizona State University’s Kathryn Sorensen has dubbed “assigned water” – water that results of conservation efforts, set aside in the Colorado River Basin’s reservoir storage accounts for the future use of whoever did the conserving. Sort of.
While most of of the attention right now is focused on the top line conflict among the basin states, there remains a need to get the down-in-the-weeds details right.
Originally developed as a tool called “Intentionally Created Surplus” in the 2007 Colorado River operating guidelines (who names these things?), Assigned Water has become a critical tool for managing water use reductions in a way that helps ensure reliability for the water users to whom the tool is available. It’s extremely valuable, but is not without its drawbacks – crowding out conservation efforts that might benefit the basin as a whole, inadvertently shifting system water that again might benefit the basin as a whole into an individual water agency’s savings account, and delaying shortage declarations that might have enforced deeper cuts, sooner.
First a Thank You, and a large debt of gratitude for the efforts of Colorado River Working group. Terrific deep dive into the intended and un-intended results of creating “assigned water”. The background details make is very easy to see the recommendations as logical. Well done.
The one area that might still need work is the Assigned Water Opportunities in the Upper Division. Since the amount of water used in trans-basin diversions prior to the Compact are not considered in the upper basin states usage, I worry that this might be an opportunity create a surplus “assigned” water from water that is no longer even in the Colorado river basin. For example CO river water that has been diverted out of the the basin to the eastern slope of Colorado, could be conserved and create assigned water in the CO River basin.
The amount water involved in dozens of trans-basin diversions in Upper basin states is enough to make a material difference to the rest of the CO river basin. So, it’s a concern even though most upper basin are not currently working on programs that would create assigned water. They do have the opportunity to conserve their trans-basin diversions water, and it seems fair that those savings should go to the basin as a whole.
Just a thought.
Glad to hear some consideration being given to evaporative losses.
As a recent article in another place pointed out that a lot of the current problem in Iran is a result of building dams in areas that can’t fill or support such pools of water so they ended up depleting their groundwater and evaporating it away. Had they left well enough alone (pun somewhat intended) they’d have wetlands and groundwater.
All the cries about California not having enough water storage are perhaps things that should be questioned a lot more but at least the California groundwater regulations are being worked on.
I’m not sure how much of New Mexico and Colorado water issues could be helped further along by soaking in more water instead of losing it to evaporation…