US Army Corps of Engineers

Lower Granite Dam & Lake

June 2026

Day of MonthTotal Generation MWhAverage Generation MWStation Use MWhInflow kcfsTotal Outflow kcfsGeneration Flow kcfsSpill kcfsMidnight Reservoir ElevationAverage Forebay ElevationAverage Tailwater ElevationAverage Head feetMidnight Lewiston Gage ft
1 67.30 66.50 12.10 53.70 735.53 735.38 633.89 101.49 736.17
2 60.20 60.80 12.10 48.30 735.39 735.41 633.63 101.78 735.93
3 55.70 55.30 12.10 42.80 735.49 735.51 633.61 101.90 736.05
4 51.60 52.60 12.10 40.10 735.19 735.30 633.72 101.58 735.73
5
6
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8
9
10
11
12
13
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30
TOT            
AVG    58.70 58.80 12.10 46.23 735.40 735.40 633.71 101.69 735.97
MAX    67.30 66.50 12.10 53.70 735.53 735.51 633.89 101.90 736.17
MIN    51.60 52.60 12.10 40.10 735.19 735.30 633.61 101.49 735.73