OCR Text |
Show -19- ing the dam. These costs have been compared wtih the increase in output, in the following table: Increase in raise of water surface From 557 to From 575 to __________________________________________575 feet__________582 feet Increase in construction cost............ $ 3,134,000 $ 1,258,000 Increase in annual cost: Interest and amortization ........ 145, 893 58, 545 Operation and maintenance.............................................................. Depreciation ................................ 1,355 529 Total..................................... 147, 248 59, 074 Increase in anual power output, kilowatt-hours............................ 269, 000, 000 79, 000, 000 Cost per kilowatt-hour for the increased output ¦¦......................_______0. 00055_______0. 00076 The above table indicates a fast-mounting cost for the increased energy obtainable with a raise in height of dam, but with such costs still well below the cost with the 550-foot or 557-foot dam, even though the height be increased to 582 feet. INTERFERENCE WITH BRIDGE CANYON SITE At the head of the Boulder Canyon Reservoir lies the Bridge Canyon dam site, considered the most desirable of the sites on that section of the river. River level there is at elevation 1,207 feet, with 10,000 second-feet flowing. The extent of interference by Boulder Canyon is presented in the following table: With 1938 With 1988 develop- develop-______________________________________ment______ment 557-FOOT DAM AT BOULDER CANYON Maximum water level at Boulder1...................... 1,204 1,204 575-FOOT DAM AT BOULDER CANYON Maximum water level at Boulder...................... 1,222 1,222 Maximum encroachment ..........................feet.... 16 16 Greatest encroachment, 1897-1929............do...... 3 10 Time encroached, 1897-1929............per cent.... 0.3 13 582-FOOT DAM AT BOULDER CANYON Maximum water level at Boulder...................... 1,229 1,229 Maximum encroachment ..........................feet.... 23 23 Greatest encroachment, 1897-1929............do...... 8 15 Time encroached, 1897-1929..............per cent....________8_______25 interference negligible, limited to backwater effect at high flood. |
Source |
Original book: [State of Arizona, complainant v. State of California, Palo Verde Irrigation District, Coachella Valley County Water District, Metropolitan Water District of Southern California, City of Los Angeles, California, City of San Diego, California, and County of San Diego, California, defendants, United States of America, State of Nevada, State of New Mexico, State of Utah, interveners] : California exhibits. |