WSP09412 - Laserfiche WebLink

Home Browse Search

... r; '" ~:l 1'-' i.- Diffuse-source projects will control salt contributions from a larger areal extent than point-source control projects, The basic con- cept is to selectively remove the saline (over 1,500 ppm) low flows from a stream and to bypass the high flows. The low flows would be desalted, evaporated, or otherwise utilized away from the stream, Potential diffuse source-control projects are also shown on Plate 8. Irrigation-source control projects, as in- dicated on Plate 8, would consist of (I) im- provement of irrigation scheduling and man- agement and (2) water systems improvements. The irrigation scheduling and management activities would be aimed at reducing the volume of deep percolation to ground water through saline geologic forma- tions, which would reduce the salt load un- der present conditions, Existing irrigation systems would be studied to identify poten- tial structural measures to reduce losses, in- crease operating efficiency, and further cur- . ., riv . Other studies included in the program will be a mathematical model of the river, eco- nomic evaluations of water quality, an insti- tutional and legal review, and studies of ion exchange process systems. Other existing programs such as the Western V.S, Water Plan Study, the weather modification pro- gram, and the geothermal resources program will provide important additional input to the Colorado River Water Q!!ality Improve- ment Program, Establishment of Water Quality Stondards The State Water Resources Control Board (SWRCB) adopted a temperature control policy for the Colorado, New, and Alamo rivers on January 7, 1971, which was revised on October 13, 1971. The adopted policy con- tained the following language to exclude irri- .gation return flows from control: "Irrigation return waters are not considered elevated temperature wastes for the purposes of this policy." The SWRCB adopted changes to the pol- 28 icy on October 13, 1971, which included a specific numerical temperature maximum in the Colorado River for each month of the year, The revised policy is now being consid- ered by EP A for adoption as. federal water quality standards, Preliminary Californio Interim Water Quality Management Plan Passage of the California Clean Water Bond measure in November 1970, together with associated federal and local funds, has made $1 billion available to the State of Cali- fornia for wastewater treatment programs. Federal guidelines require that fully devel- oped pollution control plans for all regional areas must be approved by state and federal agencies by July I, 1973, to qualify for fund grants. Prior to that date, the award of con- struction grants will be based on interim plans, The interim plans were required by July I, 1971. Two re orts re ared by the Colorado River Basin Region ater uahty Control Board covering the east and west Colorado River Basins were reviewed, The draft of the report for the East Colorado River Basin con- tained the statement: "There shall be no dis- charge of sewage to the Colorado River from the California side regardless of degree of treatment," It was the Board's view that such a statement would be detrimental to Cali- fornia's Colorado River water users because return flow credit in computing consump- tive use would be eliminated. Such a policy would also be costly to implement and a wasteful use of water resources, On May 13, 1971, the Principal Hydraulic Engineer presented the Board's views on the report at a meeting of the Regional Board. The Board recommended that there be no prohibition on the return to the Colorado River of adequately treated waste water and sewage so as to allow California water users to receive full credit for return flows. These recommendations were later incorporated into the revised report, /