WSP00180

• File Number: 8271.300
• Description: Colorado River Basin Salinity Control Program - General Information and Publications-Reports
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 3/1/1981
• Title: Feasibility of Financial Incentives to Reuse Low Quality Waters in the Colorado River Basin
• Water Supply Pro - Doc Type: Report/Study

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However, other strategies for salt load reduction may increase
consumptive uses, reducing the amount of water available for downstream
use. The most relevant example is consumptive industrial reuse wherein
heavy salt concentrations are not returned to the river while the waters
containing the salt are lost rather than being returned to the stream.
The extent of the net water loss will, naturally, depend on the extent
to which the heavily saline waters being reused substitute for evapora-
tive losses of higher quality water.

As long as the reused waters have a salinity concentration higher
than the river at the point of their return flow, consumptive reuse will
reduce the concentrations there and at some downstream points. Farther
downstream, if the river's salinity concentration increases to a level
greater than that of the water consumptively reused, the reuse will
cause an increase in downstream concentration of river salinity.
Whether or not the immediate beneficial effects of reuse on salinity
will offset the downstream losses from reduced water availability de-
pends on both the existing salinity levels (i.e., where we are on the
salinity-loss function) and on the marginal value (shadow price) of
water quantity.

Since both reduced concentration and water quantity loss (or
gain) are relevant, we will present estimates of the values related to
each. Regarding the benefits from concentration reduction, irrigation,
domestic, and industrial uses are all affected (although much more is
known about the effects on irrigated agriculture than about the other
activities). For each of these activities, the valuation of a reduction
in concentration is approached in a reverse fashion: by estimating the
damages from increases in the concentration.

The applicable measure of losses depends on how the affected
parties will respond to the increase. Each party has a variety of
possible responses, including doing nothing and accepting the consequent
losses; changing irrigation (or other water application) practices in
ways that reduce damages more than increasing costs; changing cropping
patterns; changing sources of water; treating the water, etc. The value \
of damages associated_J1i--E.!L..!.~_.mo.!i..L?:,g'!{,,!!,t;ageous response is the value
tObe used_Cis thedi.rect benefit from a sa1.liiTtyconc:entrat1on ,reductio:':,.

We now review the important studies in the literature of salin-
ity damage and water value, leading up to the presentation of our best
current estimates of net benefits from salinity reduction.

Irrigation. Major concern over water quality in the Lower Colo-
rado River was first shown in the "Conference in the Matter of Pollution
of the Interstate Water of the Colorado River and Its Tributaries" held
in January, 1960 under the joint sponsorship of the riparian states and
the Federal Water Pollution Control Administration. The Colorado River

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