According to the U.S. Bureau of Reclamation’s new Consumptive Uses and Losses Report (pdf), consumptive use of Colorado River water in the states of the upper basin (Colorado, New Mexico, Utah, Wyoming and a sliver of Arizona) reached 4.281 million acre feet in 2011, the highest on record.

The previous high was 4.245 million acre feet in 1994. (Source: The Colorado River Documents 2008, page 2-15 up through 2008, consumptive use reports for the rest).

The state of Colorado also had its biggest Colorado River water use year ever at 2.495 million acre feet in 2011.