Page 93


Page 93
Colorado River problem
Is Part Of,8
Full text
398 WEYMOUTH ON THE COLORADO RIVER PROBLEM the lower river, having in mind at all times the paramount importance of irrigation and flood control. Some of the results of these studies are embodied in this discussion. The section of the river through the Park has been disregarded, because of public aversion to its development, while the part above the Park is so far distant from large power markets that its development will not be economical until the entire power possibilities below the Park become fully utilized. The more important factors involved in the proper development of the entire section below the Park in the order of importance are, as follows: 1.—Adequate storage capacity for irrigation and flood control with a minimum of evaporation loss. 2.—Construction cost. 3.—Maximum power output with maximum flexibility. 4.—Minimum destruction of developed and undeveloped property. Adequate Storage Capacity for Irrigation and Flood Control.—This factor is by far the most important, as the use of water for irrigation must take precedence over that for power in the Colorado River Basin. The object of the development should be first, the protection of present irrigated lands from the ever-present dangers of inundation and water shortage and thereafter the provision of adequate storage capacity to permit the utmost development of the water resources of the Colorado River Basin. Other waters cannot be substituted to irrigate lands in the Colorado River Basin, but other sources can provide power. Under present conditions less than 1,000,000 acre-ft. of active storage are required to insure an adequate irrigation supply for the Lower Colorado areas. With further development throughout the Basin, this volume will soon increase rapidly. In the writer's report of February, 1924, it was estimated that 25,000,000 acre-ft. would ultimately be required for this purpose alone if up-stream developments did not create material hold-over storage. Undoubtedly, considerable storage of this type will materialize, but it is believed that 15,000,000 acre-ft. of storage will be required for this purpose on the lower river. The present silt inflow at Boulder Canyon is estimated at 80,000 acre-ft. annually. It will gradually decrease as up-stream reservoirs are constructed. To prevent the encroachment by silt on the storage needed for irrigation purposes for a long period of years, an additional capacity of 5,000,000 acre-ft. is needed. Floods should be limited to not more than 40,000 sec-ft. at Yuma, as discharges of more than 50,000 sec-ft. are difficult of control and seriously endanger the present levees. The uncertainties attending any change in the regimen of a stream like the Colorado River dictate that ample provision should be made to meet contingencies. Under present conditions, such control will require 8,000,000 acre-ft. of storage, decreasing to 5,000,000 acre-ft. when the up-stream development becomes considerable. From the foregoing it will be seen that a total capacity of 25,000,000 acre-ft. should be provided to meet future conditions. That such a capacity

Cite this Item

When linking to this object, please use the following URL:,1700



Subscribe to recent comments

There are no comments yet. Be the first to comment below!