WSP11033

• File Number: 8272.100.70
• Description: Colorado River Basin Salinity Control Forum
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 6/1/1975
• Author: CRBSCF
• Title: Water Quality Standards for Salinity Including Numeric Criteria and Plan of Implementation for Salinity Control
• Water Supply Pro - Doc Type: Report/Study

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CHAPTER III
SALINITY OF THE RIVER

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The Colorado River Basin covers an area in the United States of

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242,000 square miles, approximately one-twelfth of the conterminous
United States, and 2,000 square miles in Mexico. It extends 1,400
miles from the Continental Divide in the Rocky Mountains to the Gulf

of California. Historically, the river, from both natural causes and

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man's activities, has carried a large dissolved mineral load resulting
in salinity concentrations higher than for most other major rivers.
The Colorado River Basin has a population of about 2.25 million

and through export projects, its water provides either full or

. supplemental supplies to about 12 million people in the Southern

California, Denver, Salt Lake City, Cheyenne, and Albuquerque areas.

With the completion of the Central Arizona Project now underway, the

4t Phoenix and Tucson areas will be served from the lower main stem.

Within the Basin, the regional economy is based on irrigated agriculture,

mining, forestry, manufacturing, oil and gas production and tourism.
. Approximately 2t million acres are irrigated within the Basin, and
hundreds of thousands of acres are also irrigated with water exported

from the Basin. About one-half million people and 425,000 irrigated

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acres in Mexico are served with Colorado River water.

Sources of Salinity
Generally, salinity of the river increases from its headwaters
. to its mouth. This increase is the result of two basic processes --
salt loading (adding salts) and salt concentrating (reducing water
supply). Salt loadinr; results from both natural conditions and

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