Figure 16.37
Pre- and post-dam stream hydrograph. This stream hydrograph shows flows in the Colorado River downstream of Glen Canyon Dam in 1942 and 1994. Before the dam was built, stream discharge peaked at over 90,000 ft3/s with the late spring snowmelt (1942 line), creating a major flood event. The 1994 levels represent typical flows after the dam was built. Peak discharge periods, such as the one seen in 1942, were eliminated.