Sandbars—from small nooks and crannies to some the size of football fields—were formed by an artificial flood unleashed on the Grand Canyon. On a couple of big sandbars there were already beaver tracks, bighorn sheep tracks.

Whatever benefits come from this year’s flood will be eroded within 18 months because additional floods are needed every year to 18 months, but no other high-flow releases are scheduled until after 2012.

Read (National Geographic)