Risks of 2016 Colorado River shortage declaration pretty much gone, risks of 2017 also shrinking

The Bureau of Reclamation’s latest 24-month study, out this afternoon (pdf), shows continued improvement on the Colorado River system’s big reservoirs as a result of the hella rainy spring and summer, and therefore a continued reduction in the risk of a Lower Basin shortage declaration.

the May precipitation anomalies that bailed out the Colorado

the May precipitation anomalies that bailed out the Colorado

The number to watch is a Lake Mead elevation of 1,075, and the date to watch is January 1. The forecast in the latest 24-month study puts us at 1,082.12 on Jan. 1, 2016. That means that unless something crazy happens, like El Chapo’s tunnel dudes drill a hole in the bottom of Hoover Dam and steal 700,000 acre feet of water, it looks like a 2016 shortage declaration is completely off the table.

For 2017, things are also looking better. The current 24-month forecast puts it at 1,078.13 on Jan. 1, 2017, three feet above the danger line. That’s the midpoint of the forecast, meaning that there’s a better than 50-50 chance we won’t have a shortage in 2017. Three feet is not much, so the risk is clearly non-zero. The Bureau’s been running more sophisticated probability analyses, but I haven’t seen them, so I don’t know what the numbers say.