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003144 Page 43 2. Effects of increased water demands given current institutions The initial conclusion that flow augmentation produces little change in beneficial water use under current demand conditions immediately raised the question of how that conclusion might change if proposed development projects were to be built, thereby increasing the physical capability to satisfy additional water demands. Water demands projected for the full development scenarios were about 30 percent above those of the current scenario. As shown in Table IV-2, the conclusion is not greatly changed under the full development scenario. Average annual Upper Basin shortages were only about 18,000 acre-feet annually under the full development scenario and were unaffected by increased flows. These shortages are "local" ones, which is to say that they occur at high elevations where they cannot be alleviated by the operation of existing or planned storage and diversion facilities. They are not limitations imposed by the water allocations assigned to the Upper Division states under the Colorado River Compacts, because under the simulated conditions, there were no shortages in the Lee Ferry delivery, so no curtailment of Upper Basin uses was necessary. ~ ~ Lower Division shortages in the full development scenario are substantial. Under baseline runoff conditions they amount to an average of 644,000 acre-feet annually (nearly eight percent of total Lower Division Colorado River water demand). Nearly ninety percent of the shortages are reductions in deliveries to the Metropolitan Water District of Southern California, nearly half of total Colorado River water demand by the district, Which currently uses more than its allotted share because neither CAP nor the Upper Basin are yet able to use their full allocations.