Here’s a striking graph distributed this week at the U.S. Bureau of Reclamation’s 2014 Colorado River Annual Operating Plan consultation meeting in Las Vegas:
That’s annual unregulated* inflow into Lake Powell on the Colorado River. A couple of things worth noting:
- 2012 and 2013 are two of only four years since Glen Canyon Dam was completed with inflows less than 5 million acre feet
- Only three of the 14 years from 2000 to the present have had above average inflows into Lake Powell
- Three of the four lowest years on record have occurred during the current drought
This data isn’t new, it was just striking to me to see this graphical representation.
* “unregulated inflow” involves an estimate of what the natural inflow into Lake Powell would have been absent upstream dams and diversions