WSP01646

• File Number: 8273.100.40
• Description: Colorado River Basin Salinity Control - Federal Agency Reports - BOR
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 2/1/1989
• Title: Salinity Update - Special Edition February 1989
• Water Supply Pro - Doc Type: Report/Study

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High salinity concentrations
result from two general processes:
salt loading and salt concentration,
Salt loading Increases the amount of
salt added to a given amount of
water, and salt concentration
decreases the amount of dilution
water available for a given amount
of salt,

Specifically, salt loading in the
Colorado River system results in the
addition of mineral salts from
natural and manmade Sources, Salt
concentration results in the rise in
salinity through beneficial
consumptive use of waters and
associated streamflow d(", "letions in
the Basin that concentrate the salt
burden into a lesser volume of
water, Generally, the application of
irrigation water results in increased
salt loading because of salt leaching
and the concentrating effects of
consumptive use, The total salt
concentration in the river fluctuates
annually with the overall Basin
water supply,

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050

000

850

800

750

700

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850

600
1985 1990

The Colorado'River, at Its H
headwaters in the'mountalns of
north-central Colorado, has a
salinity (dissolved'mlnerals)
concentration of only about
50 mg/L (mlUigrams per liter), me
salinity concentrations
progressively Increase as the river,:
flows downstream,as a result of
water diversion.. evaporation from _
reservoirs, and salt,contrlbutions,
from a variety of sources, Recent
record-high flows have flushed an4,
filled the major reswvoirs, resultlnf
in significantly lower salinity levels:
at Imperial Dam - from an annual;
average of 826 mg/L In 1982 to '
621 mg/L (provlslol1a1) in 1987,
Without control measures, however;
the concentration is projected to
increase, following the overall rlsinlf'
trend shown in figure 2, possibly
reaching a level of 966 mg/L' at
Imperial Dam by about 2010,

.. The current projection is from 1988
Evaluation ofSallnity Control Programs
in the Colorado River Basin.

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1995 2000 2005 2010 2016 2020
Va""

Figure 2, - Salinity projections with and without further COntrols 10/88,