The three graphs show discharge, temperature, and rainfall
for the Colorado River below the Glen Canyon Dam in
Arizona. Discharge was measured at Phantom Ranch in
the Grand Canyon.
Water releases from Glen Canyon Dam are tied to demand
for electricity produced by the hydroelectric power
plant at the bottom of the dam. Recently, environmental
scientists noted that the lack of natural floods below
the dam was causing beach erosion and changing environments
for native species in the Grand Canyon.
! Examine the graphs to interpret what was happening
on the Colorado River. Use the information to answer
the questions at the bottom of the page.