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M co en .... C- o concerning temperature objectives for the Colorado River are: 1. Give consideration to the effects of such temper- ature objectives on all existing beneficial uses rather than to the single purpose of providing optimum temperatures for fish. Z. Gather more temperature data and give more weight to historical stream temperatures. 3. Adopt a more flexible definition of recommend- ed temperature than "recommended tempera- tures refer to mean daily temperatures..." 4. Establish objectives that would allow existing agricultural projects on the Colorado River in the Lake Havasu to Mexico section of the river to continue their present operations. 5. Initiate discussions with Arizona in order to ar- rive at identical thermal objectives for each state. 6. Delay action on establishment of a temperature policy until more complete studies are made, conferences held between all interested parties, and full consideration given to the future effects of establishing a temperature policy. The SWRCB took no action but suggested that the Department of Fish and Game and all other concerned parties hold meetings to consider the effects upon all other beneficial uses and draft recommendations that are compatible with the beneficial uses of the State's waters. The Board's staff worked closely with the Colorado River water contractors, the Colorado River Basin Regional Water Q!!al- ity Control Board, and the Attorney General for the purpose of drafting satisfactory tem- perature standards. The objectives originally proposed by the Regional Board were revised and adopted at a meeting on April 24, 1969. Significant changes and additions to the ob- jectives made by the Regional Board are as follows: 1. Abandoned the proposal of the Department of Fish and Game that absolute maximum tempera- tures be established for each month, and estab- lished an allowable temperature rise above his- torical (most recent) temperatures for each month. Z. Added language to require that temperature readings be made after a return flow is thorough- ly mixed with the river's flow. 3. Added language to state that engineering judg- ment would be applied in analyzing temperature data to determine if a forced rise is occurring. 40 4. Modified controlling language to state that only discharges from controllable sources would be subject to modifications or shutdown, if a forced temperature rise occurs. (This qualification means that irrigation return flows would not be subject to shutdown.) In August the SWRCB heard testimony on, and considered, temperature standards for the Colorado River, but took no action on the matter. New Mexico Statement on Salinity In September 1969 New Mexico presented a statement to the Water Resources Council which included comments on salinity. New Mexico pointed out that the Upper Basin states ratified the Colorado River Compact, thus permitting the Lower Basin states to develop. Under the Compa~t, the Upper Basin states are also entitled to develop at their own rate and use their allocation of wa- ter, thereby reducing the flow to the Lower Basin. A necessary consequence of such use is the degradation of the quality of the water flowing to the Lower Basin because con- sumptive use concentrates all of the salt load of the river in the remaining flow and thus increases the concentration of dissolved sol- ids in the portion left for use in the Lower Basin. The statement also declared that, since Upper Basin development has not been as rapid as that of the Lower Basin, the Lower Basin has been able to use a water supply which is better in both quantity and quality than it is ultimately entitled to. Therefore, it would be extremely inequitable to inhibit federal assistance in the development of Upper Basin water projects by charging these projects with the mitigation of Lower Basin salinity. Consequently, New Mexico believes that under the Compact the Lower Basin must accept lower quality water as the Upper Basin develops. California Conference on Colorado River Salinity A conference was called by the State Water Resources Control Board and held in Palm Springs, California, on September 17,