Here’s the scoop. The Bureau of Reclamation (BR) recently published a press release explaining the predictions for the remainder of this, and the next water year. The Bureau’s press release includes all kinds of vital information, but is also not the easiest read. For someone not familiar with the jargon usually included in Bureau of Reclamation releases, it will take at least a few Google searches to figure it out.
The Bureau of Reclamation has, for the 2013-14 water year (ending Sept 30st), made an unprecedented prediction regarding total output from Glen Canyon Dam. This is such an exceptional move in that it is the first time since dam operation began that minimum output has been lowered to a point below 8.23maf (million acre feet). This output downgrade is following the new guidelines outlined in the 2007 Colorado River Interim Guidelines for Lower Basin Shortages and Coordinated Operating for Lake Powell and Lake Mead. The Interim Guidelines were signed by the Secretary of the Interior following extensive research and consultation with the seven affected states in response to rising concerns about water supply shortages due to the ongoing drought.
The severity of the situation is best defined in the raw numbers. According to the Bureau’s latest numbers, at the end of the 2012-13 water year total basin storage will be at 29maf, which is 49% of capacity. The situation at Lake Powell is similar; it will end the water year at 10.4maf, only 43% of capacity. Total inflow into Powell this year was only 4.33maf, or 40% of the 1981-2010 average.
So what do these numbers add up to? Well, according to the 2007 Interim Guidelines, if the elevation of Lake Powell falls below 3575 ft. at the close of the water year (September 30th), which it is predicted to do this year, then the Bureau must shift operations from the upper elevation balancing operating tier that they have been on up till now to the mid-elevation tier in the following year.
What this means to water users in the lower basin is that total output will be lower than total allocation for Arizona, Nevada, and California. Though no shortages are predicted in 2014 or 2015, Terry Fulp, Lower Colorado Regional Director for the Bureau of Reclamation, the first significant chances for reduced delivery to the lower states are in 2016 if input does not significantly rise before then.
What does this mean for river runners in Grand Canyon next year? Well, we can probably expect more low water months like this September and October to become more and more the norm. Next year may be a great opportunity to see the river at a low level that we rarely get to see it at, the rapids will feel and look much different offering a transformed kind of whitewater experience. Whether the downgraded water situation ends up looking like a fluke or a long-term trend, it is safe to say that river runners will be getting to know the low water runs through Grand Canyon.
Most of the information provided could be found at: http://www.usbr.gov/uc/water/crsp/cs/gcd.html
Director Fulp’s quote along with the Bureau’s most recent press release could be found here: http://www.usbr.gov/newsroom/newsrelease/detail.cfm?RecordID=44245