WSP10624

• File Number: 8271.300
• Description: Colorado River Basin Salinity Control Program - General Information and Publications-Reports
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 8/1/1981
• Title: Role of Sediment in Non-Point Source Salt Loading Within the Upper Colorado River Basin
• Water Supply Pro - Doc Type: Report/Study

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5. Movement of sediment and solutes in streams;

6. Preliminary estimation of diffuse, non-agricultural salt

loading, and

7, Preliminary identification of areas where management and

treatment practices will reduce salt loading.

1.2 Salinity Problem

The Colorado River Basin spans from Wyoming, Colorado and Utah

down to Arizona and California with a drainage area of more than

200,000 square miles, At the headwaters the average salinity (concen-

tration of solutes, or the misnomer total dissolved solids) in the

Colorado River is less than 50 mg/l, This progressively increases

downstream until, at Imperial Dam, the modified condition is 865 mg/l

(Maletic, 1973). Salinity values refer to the concentration of

solutes and are reported in milligrams per liter (mg/l). This weight

per volume unit of concentration is nearly equivalent to 'parts per

million (ppm) up to concentrations of 7000 mg/l, "Present unmodified

condition" refers to conditions during 1941-1968 modified to reflect

all upstream existing projects in operation for the full period,

Projection of future salinity levels without a control program

suggests that values of 1250 mg/l or more will occur at Imperial Dam

by the year 2000. One projection used in the Lower Colorado Region

Comprehensive Framework Study (based on a U,S. Water Resource Council

study) foresees such a level being reached by 1980, The salinity

problem is especially severe due. to the importance of this region

of the nation for energy development, which almost unavoidable will

result in increased salinity levels (Coos, 1973; Schmehl and McCaslin,

1973).

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