7068

• UCREFRP Catalog Number: 7068
• Author: Bishop, B. A. and D. B. Porcella.
• Title: Physical and Ecological Aspects of the Upper Colorado River Basin.
• USFW Year: 1980.
• USFW - Doc Type: 17-55
• Copyright Material: YES

38

.

waters, it would also reduce river flows, a situation that must be stud-

ied carefully in terms of fish and wildlife implications.

Recreation. Recreational activities in the Upper Colorado River

Basin have grown steadily over the past several years, as indicated by

figure 4. The major recreational pursuits include boating, fishing. swim-

ming. float trips. camping, off-road vehicle use, hunting. hiking and

touring (particularly visiting the many national parks and monuments).

The increasing intensity of recreational activity within the basin, as

well as the additional human wastes introduced into the aquatic and ter-

restria1 environments, will certainly exert new and increasing stresses

on the fish and wildlife communities of the basin.

Urbanization.

The upper Colorado region is sparsely populated with

an average density of about three persons per square mile. In 1970 there

were only seven towns in the upper region with populations greater than

5.000. Only two of these seven towns had populations greater than 20,000.

Overall, 72 percent of the towns in the Upper Colorado Basin have popu1a-

tions of less than 500. and only 9 percent of the towns had populations

greater than 2,000. Less than 3 percent had populations greater than

5.000. Farmington. New Mexico. is the largest city in the Upper Colorado

Basin with a 1970 population of 21,979. Of the water used for municipal

and industrial purposes, a large proportion is exported for use outside of

the hydrologic basin. Future water developments for municipal supplies

involve further large exports which will deplete downstream flows and

threaten to dewater some high mountain streams. Again. such future proj-

ects have significant implications for fish and wildlife.

39

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1964

1972

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Figure 4. Million Visitor Days of Recreation, Upper Main Stem,
San Juan and Green River Basins

Source: Utah Water Research Laboratory, Colorado River Re~ional
Assessment Study. Report to the National Commission on Water Quality
(Lo~an, Utah, Utah State University, October 1975).