Despite a last-minute frenzy of deal-making, the federal government announced that it will begin taking “protective actions” on the Colorado River, where a long-running drought has put the water supply for 40 million people at risk. The seven states that use the river had been trying to broker their own solution, a collective water-sharing deal, with a Jan. 31 deadline to get it done. While most states had agreed, California and Arizona couldn’t finalize the agreement in time.