Mile 14.7, Glen Canyon Dam, Downstream View from River Left (Stake 2638b)

View Larger Image
23 December 1889
While the Brown-Stanton expedition would eventually switch from an instrument survey to a purely photographic survey of the canyons of the Colorado River in order to save time, at this point, they were still conducting an instrument survey. Three members of the expedition, with plane table and stadia rod, are visible in the center foreground. Shrubs, likely Mormon tea and saltbrush, grow upon the slope in the foreground, while the river’s edge is barren.
Photo credit: Franklin A. Nims, 57-RS-236, courtesy of The National Archives

View Larger Image
29 October 1992
A century later, the presence of Glen Canyon Dam, which is just upstream, affects this view and all others downstream that show the river corridor. Large power poles dominate the skyline, a small power line crosses in the midground, and riparian vegetation, mostly netleaf hackberry and non-native tamarisk, has become established along the river corridor now protected from large floods. The shrubs growing along the slopes include Mormon tea, sand sagebrush, grizzlybear pricklypear, and non-native Russian thistle. A small area of biological soil crust is apparent at lower left.
Photo credit: Robert H. Webb

View Larger Image
20 April 2011
The netleaf hackberry have increased in both stature and number of individuals in the ensuing two decades, and the tamarisk visible along the opposite bank has increased as well. Many of the Mormon tea persist, while some of the four-wing saltbush and sand sagebrush have died, as has the grizzlybear pricklypear. The biological soil crust is still present albeit subdued, and the large boulder in the center foreground has rotated.
Photo credit: Robert H. Webb