Four months ago, the outlook for the Colorado River was so dire that federal projections showed imminent risks of reservoirs dropping to dangerously low levels. But after this winter’s major storms, the river’s depleted reservoirs are set to rise substantially with runoff from the largest snowpack in the watershed since 1997. The heavy snow blanketing the Rocky Mountains offers some limited relief as water managers representing seven states and the federal government continue to weigh options for cutting water use.