| Table 5. – Computed seepage rates from Crater Lake 1 |
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1 Precipitation is that observed at Crater Lake Weather Station. Runoff includes precipitation and is computed as 1,386 acre-feet per inch of precipitation. Volume change is computed from observed change in stage and constant lake area of 13,140 acres. Annual evaporation toss is assumed constant as 23 inches (25,180 acre-It) per year. Lake level is partly estimated because of lack of data in winter and spring periods.
| TABLE 6.-Computation of annual evaporation loss from Crater Lake |
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| TABLE 7.-Altitude of water surface in Crater Lake, 1878-1963 |
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