In the contentious, yearlong negotiations over how to share the pain of Colorado River shortages, California officials leaned on their state’s status as the basin’s most senior water rights holder — or the last in line to take cuts when supplies run low — to fend off arguments it should bear the brunt of reductions.

The gambit worked, ultimately sparking a compromise in which California will share cuts with Arizona and Nevada over the next three years. The deal means the state will give less than 10 percent of its annual allocation, in line with its original offer.