BY PAUL E GRAMS, JOHN C. SCHMIDT, SCOTT A. WRIGHT, DAVID J. TOPPING, THEODORE S. MELIS, AND DAVID M. RUBIN
In 1963, the U.S. Department of the Interior’s Bureau of Reclamation finished building Glen Canyon Dam on the Colorado River in northern Arizona, 25 kilometers upstream from Grand Canyon National Park. The dam impounded 300 kilometers of the Colorado River, creating Lake Powell, the nation’s second largest reservoir...