7832

• UCREFRP Catalog Number: 7832
• Author: U.S. Bureau of Reclamation.
• Title: A Pilot For Long-Term Monitoring Of Resources On The Colorado River In The Grand Canyon Using Geographic Information Systems.
• USFW Year: 1995.
• USFW - Doc Type: \
• Copyright Material: NO

POST--DAM (196-5 -1983)
100 DESERT 1
OLD HIGH
WATER ZONE
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NEW HIGH WATER ZONE ,
Z
60
g
Q FLUCTUATION ZONE
5 4

40 TALUS
POST-DMI HIGH
WATER UNE
20

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-l PRE^DAIJ SLLT/SAND TERRACES - .-RIVER.SANp:;:..... RNER

200 150 100 50 Q
FEET
Figure 1. - GCES/GIS post-dam study area profile.
Site No. 5 is located from river mile 60 to 72, and includes 1 mile of the Little Colorado River
upstream from the mouth. The confluence of the Colorado and Little Colorado rivers occurs at
about river mile 61.5. The Little Colorado flows from the east and merges with the southward
flowing Colorado. The pilot site is bounded by the Navajo Indian reservation to the northeast
and by Grand Canyon National Park on the west and southeast. A map of site No. 5
representing the 1990 base data and resource study sites can be found on figure 3 at the back
of this report.
GCES Base Map Production
A GIS was determined to be necessary in 1989 for archival and analysis of the data being
generated through the GCES. A base map product of the scale and accuracy required for
detailed GIS analysis of the monitoring sites was not available. The initial effort requires the
development of a base map product specifically for the GCES special studies and monitoring
sites. A photogrammetric product was established to develop both a hard copy and a digital
base map product for each of the monitoring and special study sites.
Specific technologies were used in the development of the large-scale topographic base map
products used in the GCES/GIS mapping effort. A horizontal and vertical control network was
established within each monitoring site through conventional survey methods. Aerial
photography was collected for photogrammetric data. The GCES program established the
control network and used the aerial photography to develop the topographic and orthophoto
base map products. The various technological components involved in the development of the
base map products are shown on figure 4.
4