With Lake Mead ending 2019 at elevation 1090.49 feet above sea level – up 9 feet for the year – it’s worth visiting the Bureau of Reclamation’s classic “structural deficit” slide and seeing how it compares to 2019’s real world data. First, a reminder of where the oft-quoted “1.2 million acre foot structural deficit” comes from:
Now, let’s compare that to 2019 data, and to a “what if” scenario:
|Structural deficit slide||2019||2019 with an 8.23 release|
Look, no structural deficit this year!
Well, sorta. In order for Lake Mead to rise that much (the biggest one-year rise since the monster runoff of 2011), we needed
- reduced lower basin use (it’s the lowest it’s been since 1986, and in the case of California since 1950) and
- the release of 9 million acre feet from Lake Powell – above the Law of the River-mandated 8.23 million acre feet and
- a good year on the Colorado’s tributaries between Lake Powell and Lake Mead (they added ~1.1 million acre feet, above the recent average of ~800,000 acre feet)
Absent all that bonus water, the Lower Basin, despite its lowest use since 1986, would still have a deficit to deal with.