4001

• UCREFRP Catalog Number: 4001
• Author: U.S. Bureau of Reclamation.
• Title: Colorado River System Consumptive Uses and Losses Report 1976-1980.
• USFW Year: 1981.
• USFW - Doc Type: Washington, D.C.
• Copyright Material: NO

Grand Junction, Montrose, and
Glenwood Springs are the principal
towns in Colorado. Moab is the only
major community in Utah.
Mineral production is the predomi-
nant industry. This area is the
Nation's chief source of molybdenum and
is a major source of vanadium, uranium,
lead, zinc, coal, and gilsonite.
In the Upper Main Stem reporting
area, as in that of the Green River,
agriculture centers around production
of livestock which feeds on irrigated
lands to complement the large areas of
rangeland. There is somewhat more
diversification of crops in the Upper
Main Stem, however, with some major
land areas devoted to corn, beans,
potatoes, table vegetables, and
fruit. This diversification is made
possible by climatic and topographic
conditions which create favorable air
drainage and minimize frost damage.
Irrigation consumptive use accounts
for over half the water use in the
Upper Main Stem reporting area. In an
average year about 550,000 acres of
land are irrigated. A considerable
amount (almost one-third of the total
basin use) of water is exported to
serve agricultural and municipal needs
on the eastern slope of the Continental
Divide in Colorado.
San Juan-Colorado: The San Juan
reporting area is drained by the
Colorado River and its tributaries
below the mouth of the Green River and
above Lee Ferry, Arizona. The largest
of the tributary streams is the San
Juan River which heads on the western
slope of the Continental Divide in
southwestern Colorado. Principal
tributaries of the San Juan River
are the Navajo, Los Pinos, Animas, and
La Plata Rivers. The other main
tributaries in the basin are the
Dirty Devil, Escalante, and Paria
Rivers which drain a portion of the
eastern- slope of the Wasatch Plateau
in Utah. The reporting area includes
about 38,600 square miles in portions
of Utah, New Mexico, Arizona, and
Colorado.
The largest towns are Durango and
Cortez in Colorado; Monticello and
Blanding in Utah; and Farmington in New
Mexico. Page, near Glen Canyon Dam, is
the only community of significant size
in Arizona. Most of the remaining
Arizona portion is in the Navajo Indian
Reservation.
Mining and agriculture form the
economic base for the San Juan-Colorado
reporting area. The agricultural
development is similar to that of the
Upper Main Stem with most of the
cropland devoted to livestock feeds but
with production of diversified market
crops on lands with favorable air
drainage. The main market crops are
fruit, vegetables, and dry beans.
Oil, natural gas, and coal are the
most important minerals produced.
Thermal elecric power production is
increasingly important to the economy
of the area.
Irrigation accounts for the largest
use of water, nearly 80 percent of the
San Juan reporting area use. About
250,000 acres of land are irrigated in
an average year.
Lower Colorado River Basin
Mainstream below Lee Ferry, Arizona-
California-Nevada: The Colorado River
has a length of over 700 miles and a
drainage area of 132,300 square miles
within the Lower Colorado River system
in the United States. The river flows
from Lee Ferry to the headwaters of
Lake Mead through the spectacular
canyons of northern Arizona, including
the Grand Canyon. Diversions are made
at Lake Mead to the rapidly expanding
North Las Vegas-Las Vegas-Henderson-
Boulder City area for municipal and
industrial purposes. The river below
Lake Mead courses through canyons and
broad alluvial valleys interspersed
with bordering groups of mountains.
Lakes Mohave and Havasu provide flood
control and regulatory storage below
Lake Mead. Lake Havasu also provides a
forebay for pumped export to the
Metropolitan Water District of Southern
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