US Army Corps of Engineers

McNary Dam & Lake Wallula

April 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 22640 943 120 225.10 224.10 186.80 34.60 339.40 339.25 268.56 70.69
2 21994 916 120 201.60 206.60 179.20 24.70 339.13 339.39 268.36 71.03
3 22653 944 120 193.80 202.40 184.90 14.80 338.72 338.80 268.26 70.54
4 22625 943 120 201.00 197.50 184.70 10.10 338.91 338.76 268.24 70.52
5 22620 943 120 191.30 196.70 184.50 9.50 338.53 338.79 268.20 70.59
6 21247 885 102 181.60 184.80 172.90 9.20 338.40 338.44 267.75 70.69
7 167.30 173.80 161.90 9.10 338.07 338.40 267.42 70.98
8 167.80 174.10 162.80 8.60 337.64 337.87 267.22 70.65
9 184.90 171.50 160.20 8.50 338.43 337.83 267.28 70.55
10 187.80 175.50 52.30 120.50 339.08 338.63 266.20 72.43
11 194.00 195.70 51.60 141.40 339.03 339.26 266.53 72.73
12 200.70 204.10 52.10 149.30 338.77 338.86 266.58 72.28
13 210.50 207.50 52.20 152.50 339.02 338.94 266.89 72.05
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TOT133779  702        
AVG 22296 929 117 192.88 193.41 137.39 53.29 338.70 338.71 267.50 71.21
MAX 22653   225.10 224.10 186.80 152.50 339.40 339.39 268.56 72.73
MIN 21247   167.30 171.50 51.60 8.50 337.64 337.83 266.20 70.52