AZ vs. CA:04 California Exhibits, Vol. IV; Nos. 151-192

page 49

THE ALL-AMERICAN CA2TAL. 49 of Imperial Canal to the Laguna Dam. Such a canal extension, barring accidents, which are only a remote contingency, would be useful in assuring to the Imperial Irrigation District an adequate supply of desilted water so long as there is a full supply of water in the river. As an upper section of an all-American canal it would be in use for several years during which the canal westerly from Pilot Knob is under construction, and during that time its water would be available and would in part be required to develop power which is required on the construction work. This canal extension may be made either before or after the Yuma project power development is ready for execution. Or, it is possible that it will not be made until after the Yuma power canal is in use. This latter contingency is, however, so improbable that it will be be given no special consideration at this time. When the all-American canal is completed its water will be carried westerly from Pilot Knob on as high a grade line as possible, and there will be no fall in this canal available for power at Pilot Knob. The power station at Pilot Knob may be regarded as a temporary station to be used until the canal is completed. It will furnish the power required during canal construction. Its machinery may in whole or in part be later transferred to the mesa power station No. 1, where the available fall is practically the same as that which can be made available at Pilot Knob. The Pilot Knob power station will be located near Pilot Knob at a point from which a tailrace can conveniently be connected with the present Imperial Canal below the Rockwood gate. In the canal, a short distance below the power offtake, there will be a set of regulating gates of the Stoney type and provision will be made for by-passing any water not required for power to the Imperial Canal, so that this canal may be fully supplied with water even when the water is not needed on the turbines of the power house. Any surplus water in the canal in excess of the power house and Imperial Canal requirements will be discharged through the waste gates located near Araz. At the Pilot Knob power station there will be made available for power development, upon completion of the canal down to this point, the full head of water required by the Imperial Canal, or in round numbers about 6,000 to 7,000 second-feet. It is proposed to make the first installation of turbines adequate to use up to 3,000 second-feet of this canal flow. It is estimated that this will make about 9,000 water horsepower available for use in generating electricity whenever the flow in the canal is in excess of 3,000 second-feet. This should make in excess of 5,000 horsepower available for transmission by electricity to places of use and not less than about 4,000 horsepower when the demand for water by Imperial Irrigation District is at a 149799-20------4