provided by Research Papers in Economics
An Economic Evaluation of the
Colorado River Basin Salinity
Control Program
Richard L. Gardner and Robert A. Young
Dissolved salts (salinity) adversely affect numerous urban and agriculatural users of Colorado
River water in California and Arizona. Congress in 1974 authorized a major salinity control
program. Studies of general economic benefits from salinity abatement and the cost per unit
of salinity reduction expected from specific proposed projects have been developed by the
responsible federal agencies, but no project-by-project evaluation has been published. We find
a conceptual basis for a substantial downward revision of prospective economic benefits of
salinity abatement. Revised benefits are compared with estimated costs, and only for five of
the nineteen projects do economic benefits appear to exceed costs.
Salinity (dissolved solids) in the Colo-
rado River adversely affects over 12 mil-
lion people and one million irrigated acres.
Large quantities of dissolved salts enter
the river from natural sources, including
salt springs, and from the surface runoff
from the sedimentary geologic formations
common throughout the basin. Man’s ac-
tivities, particularly crop irrigation caus-
ing saline return flows, add to the natural
salt load. Water use and evaporation from
storage reservoirs concentrates existing
salts into a smaller volume of water. The
U.S. Environmental Protection Agency
(1971) attributes 37 percent of the total
salt load to diffuse irrigation return flows,
Richard L. Gardner, formerly at Colorado State Uni-
versity, is an economist with the executive office of
the Governor, State of Idaho, Boise. Robert A. Young
is a Professor of Agricultural and Natural Resource
Economics, Colorado State University, Fort Collins.
This article derives from Richard L. Gardner’s doc-
toral dissertation, which was supported by a grant
from Resources for the Future, Inc. We wish to thank
Frank Robinson (University of California) and Keith
Mayberry of the Imperial County Extension staff for
assistance with the Agricultural Model, and Roger
Mann, William Martin, Thomas Miller and two
anonymous reviewers for their suggestions on earlier
drafts. The authors are responsible for the policy
conclusions and any remaining errors.
Western Journal of Agricultural Economics, 10(1): 1-12
© 1985 by the Western Agricultural Economics Association
primarily from Upper Basin sources, while
55 percent is assigned to natural surface
runoff and groundwater flows. Most of the
balance arises from reservoir evaporation,
as industrial and municipal contributions
are negligible.
The Colorado River Basin Salinity Con-
trol Act of 1974 authorized construction
of works, mostly to be in the Upper Basin,
to control the salinity of waters delivered
to users in the United States and Mexico.
This act was in response to rising concerns
in Mexico and in the Lower Basin states
of California, Arizona and Nevada. How-
ever, in the intervening decade, expected
increases in salinity have failed to materi-
alize, and forecasts of future salinity levels
have repeatedly been lowered. These re-
visions preceded or were independent of
the large drops in observed salinity levels
which followed the extremely high river
flows in 1983 and 1984.
The U.S. Bureau of Reclamation (USBR)
was given the lead role in implementing
the Colorado River Water Quality Im-
provement Program in Title II of the bill.
Four units were authorized for construc-
tion and twelve for investigation. The Im-
provement Program employs a number of
technologies to reduce salt pickup from