WSP03067

• File Number: 8276.856
• Description: Salinity Control Inventory Lower Gunnison Basin - Colorado River Salinity Control Program
• State: CO
• Basin: Colorado Mainstem
• Water Division: 4
• Date: 9/1/1976
• Title: On-Farm Salinity Control Investigation and Plan of Work
• Water Supply Pro - Doc Type: Report/Study

ON-FARM SALINITY CONTROL INVESTIGATIONS
for
THE LOWER GUNNISON BASIN UNIT

PLAN OF WORK
March 1976

I. INTRODUCTION

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Ultimately, salinity becomes a major problem in any large irrigation
system. In areas with highly saline soils, such as the lower portion of
the Uncompahgre Project in west central Colorado, sal inity has been a
problem since project water was first del ivered (by the U.S. Bureau of
Reclamation) in 1908. The irrigated land in the Uncompahgre Project is
within the Lower Gunnison Basin Unit, and when irrigated, the areas with
highly saline soils and subsoils are the large contributors of sa! ins
return flows. The Lower Gunnison has been designated as an irrigation
source control unit under Title II - Measures Upstream from Imperial Dac,
of Public Law 93-320 (88 Stat. 266) Colorado River Salinity Control Act,
In recent years the Lower Colorado River has developed salt loadings
that adversely affect irrigated crop production and other downstream
uses. This problem is especially severe for water del ivered to Mexico
where salt concentrations average 1,160 parts per million (ppm).

Recognition of the water qual ity problem in the region has caused a
number of studies to be made since about 1960. The Colorado River Basin
Water Qual ity Control Project was establ ished in 1960 by the Division of
Water Supply and Pollution Control, U.S. Public Health Service (prede-
cessor to the Federal Water Qual ity Administration.) This study resulted
in a series of reports on "The Mineral Qual ity Problem in the Colorado
River Basin" by the Environmental Protection Agency (1971). The occur-
rence of sal inity in the Colorado River is also documented by the U.S.
Bureau of Reclamation (1972 and 1974) Status Reports - Colorado River
Water Qual ity Improvement Program, and U.S. Geological Survey Profes-
sional Paper 441, "Water Resources of the Upper Colorado River Basin -
Technical Report," by lorns and others (1965).

This Plan of Work outl ines the plan for Soil Conservation Service inves-
tigations of the potential for USDA programs to reduce salt loadings to
the Colorado River Basin. The specific investigations will be conducted
under the Memorandum of Understanding between the Department of the
,Interior and the Department of Agriculture, effective November 27, 1974,
which was entered into under the authority of the Interdepartmental Work
Service Act of March 4, 1915 (38 Stat. 1084), as amended; the Economy
Act of June 30, 1932 (31 U.S.C. Sec. 686); and the Colorado River Basin

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