7387

• UCREFRP Catalog Number: 7387
• Author: U.S. Bureau of Reclamation.
• Title: Glen Canyon Environmental Studies Executive Summaries of Technical Reports.
• USFW Year: 1988.
• USFW - Doc Type: \
• Copyright Material: NO

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Figure 1 (below) is a hydraulic map of House Rock
Rapid, Grand Canyon, Arizona (River Mile [RM] 17).
North is to the left; the water is flowing from left to
right. The channel of the river occupied by pre-dam
discharges extends approximately up to the 925 m
contour level. The channel below the discharge of
5,000 cfs, shown here, cannot be mapped; however, some
fathometer data were obtained to allow estimates of
channel depth below the levels filled by a discharge of
5,000 cfs. The contours were compiled from aerial
photographs flown by the U. S. Bureau of Reclamation
during the Glen Canyon Environmental Studies, with
control points surveyed by the author. The contour
interval is 1 m (solid lines) or 0.5 m (dashed lines).
The hydraulic structure of the water and important
features of the channel bottom are shown by air brush
illustration. The boat on the lower left is 33 ft in
length, and is shown only for scale. Like all of the
major rapids in the Grand Canyon, House Rock Rapid is
formed by constriction of the river channel by debris
from a' side canyon (Rider Canyon enters from the west,
at the bottom of the figure). The area covered by
diagonal pattern is a sandy beach formed by deposits
from the eddy in the lower right corner of the figure.
Diagonal lines in the opposite direction indicate
vegetation.