1. Previously I provided plots and threads of Lakes Mead and Powell contents separately. This short thread deals with the combined contents of both reservoirs and projections out to Aug 2023. The combined contents provides a complete view of the problem. #coriver #ClimateCrisis 
2. This shows the combined contents back to 1935 when only Mead existed. In 1963 Lake Powell begins to fill. By 1983 the two are totally full -- even over full for a bit as Lake Powell had temp plywood boards installed to prevent downstream flooding.
3. By next year the combined contents will be below 30%, less than some years when only Mead existed before 1963. And the minimum probable projections put the contents around 20% (10 maf total) in 2023.
4. This is the same data, only starts in 1999. (Sharp-eyed readers will note that I re-normed the % full to 49.5 maf=100% from prior versions.)
5. Since 2000, with the exception of 2011, the system has either gone down, or stayed the same during the 22-year period. (And note that 2012-2013 quickly wiped out 2011 gains.)
6. There are 3 notable periods when major storage declines happened: 2000-2004, 2012-2013, and now 2020-2021. Declines are due to a combination of low flows and demands that exceed those low flows.
7. We are now entering a period where our risk of emptying these two reservoirs is much higher simply because we have less stored water -- somewhere between 15 maf today and perhaps 10 maf by 2023.
8. I shouldn't have to say it but I will:
Emptying reservoirs upon which Phoenix, Tucson, Los Angeles, San Diego and Las Vegas depend is not an option. Many acres of nationally important irrigated ag rely on this water, too.
Emptying reservoirs upon which Phoenix, Tucson, Los Angeles, San Diego and Las Vegas depend is not an option. Many acres of nationally important irrigated ag rely on this water, too.
9. Mitigating this risk of additional declines are the plans put in place to reduce demands by up to 1.4 maf/year thru the 2007 Interim Guidelines and the 2019 DCP. But Mead has to lose about another ~ 3maf for the full demand reductions to occur.
10. If these demand reductions plans are the equivalent of a parachute, there are legitimate questions about (a) the size of the parachute and (b) why are we deploying it so close to the ground given all that has transpired over the last 22 years. END
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