US Army Corps of Engineers

McNary Dam & Lake Wallula

June 2026

Day of MonthTotal Generation MWhAverage Generation MWStation Use MWhInflow kcfsTotal Outflow kcfsGeneration Flow kcfsSpill kcfsMidnight Reservoir ElevationAverage Forebay ElevationAverage Tailwater ElevationAverage Head feet
1 224.50 216.20 53.00 158.50 338.05 337.71 266.25 71.46
2 229.50 236.10 53.20 178.20 337.70 337.75 266.31 71.44
3 245.80 241.30 53.20 183.40 337.94 337.74 266.43 71.31
4 247.50 215.90 53.80 157.40 339.66 338.81 266.14 72.67
5
6
7
8
9
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11
12
13
14
15
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17
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22
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30
TOT           
AVG    236.82 227.37 53.30 169.38 338.34 338.00 266.28 71.72
MAX    247.50 241.30 53.80 183.40 339.66 338.81 266.43 72.67
MIN    224.50 215.90 53.00 157.40 337.70 337.71 266.14 71.31