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.L\:l3~ the greater rights you must acquire in order to offset evaporation. In the folders of the Board there is a study - a hypothetical study - that we worked out over a year ago showing John ~furtin evaporation studies. With a 10,000 foot pool in some years as much as 5/000 feet of evaporation occurs, 50% of the perma- nent pool. Evaporation means a constant replacement of the amount lost. Every year there is a considerable amount of evapora- tion. As you increase the surface area by increased storage you, of course, increase evaporation since evaporation is in direct proportion to the surface area exposed to the elements. I John Martin, for all practical purposes, was in full operation by 1949. All the gates were installed and it was in full operation. We have placed on this chart the histoyy of John ~furtin Reservoir according to its stor- age. The column to the extreme left repre- sents storage in terms of thousands of acre- feet. The column here, just to its right, represents the depth of the water at the face of the dam. For instance, you will note that in the first year of operation there was a capacity of 100,000 acre-feet, a depth of 50 feet at the face of the dam. The black line represents the actual histor- ical storage in John Martin Reservoir. The red line indicates the historic storage if a 10,000 acre-foot pool - permanent pool-=- had been placed on top of the conservation pool. This chart is quite revealing in many respects. Actually, as you can see, through a large part of the history of John tfurtin Reservoir, no permaneht pool was necessary at all because there was sufficient water as indicated by the black line. But we come to some critical years in which John Martin was empty - completely empty. 1952, 1953, 1954, for a short period of 1955, again in 1956, 1957 and then on to 1959. But those were relatively short periods of time during which the reservoir was completely dry, the great- est period being in 1953. I