US Army Corps of Engineers

Wanapum Dam & Lake

September 2025

Day of MonthTotal Generation MWhAverage Generation MWStation Use MWhInflow kcfsTotal Outflow kcfsGeneration Flow kcfsSpill kcfsMidnight Reservoir ElevationAverage Forebay ElevationAverage Tailwater ElevationAverage Head feet
1 13911 580 19 94.10 101.80 97.70 2.10 569.48 570.32 490.45 79.87
2 11466 478 20 78.80 84.30 80.60 1.70 568.72 568.77 488.87 79.90
3 9507 396 20 71.20 71.60 68.10 1.50 568.67 568.27 488.53 79.74
4 9514 396 19 70.70 71.40 67.80 1.60 568.57 568.57 489.06 79.51
5 7180 299 19 57.10 53.60 50.10 1.50 569.06 568.44 487.71 80.73
6 4400 183 19 33.80 33.40 29.80 1.60 569.11 568.58 486.52 82.06
7 5148 214 19 47.30 41.00 34.60 4.40 569.98 569.57 485.71 83.86
8 7450 310 19 61.30 54.40 50.30 2.10 570.92 570.47 487.38 83.09
9 7341 306 19 50.70 53.70 49.50 2.10 570.52 570.29 487.99 82.30
10 7796 325 20 52.20 58.20 53.10 3.10 569.70 570.03 487.95 82.08
11 8234 343 19 53.70 60.50 56.70 1.80 568.76 569.08 488.11 80.97
12 8205 342 18 56.70 60.80 57.40 1.50 568.18 568.24 488.14 80.10
13 6113 255 19 50.70 45.30 41.90 1.40 568.93 568.05 487.74 80.31
14 5240 218 18 41.30 39.20 35.50 1.70 569.22 568.92 487.27 81.65
15 6931 289 18 52.50 51.20 47.40 1.80 569.40 569.34 487.13 82.21
16 9795 408 21 75.80 73.40 69.50 1.90 569.73 569.66 489.15 80.51
17 11704 488 19 91.80 85.60 81.40 2.20 570.58 570.50 489.79 80.71
18 12490 520 19 92.30 90.80 86.80 1.90 570.79 569.79 489.68 80.11
19 12784 533 19 90.70 93.20 89.20 2.00 570.44 569.99 489.93 80.06
20 10270 428 19 57.00 74.60 70.80 1.80 568.01 569.32 488.92 80.40
21 4735 197 18 38.90 36.00 32.60 1.40 568.41 567.95 487.13 80.82
22 7629 318 17 62.30 56.20 52.60 1.60 569.25 568.64 487.66 80.98
23 8736 364 17 57.50 64.50 61.40 1.40 568.28 568.13 488.00 80.13
24 8699 362 18 64.00 63.60 61.20 1.40 568.34 568.14 488.28 79.86
25 6676 278 18 36.00 48.80 46.60 1.10 566.55 567.07 487.35 79.72
26 6175 257 17 50.30 45.60 43.70 1.00 567.21 566.48 487.45 79.03
27 6197 258 18 61.30 45.40 43.10 1.40 569.42 567.95 487.69 80.26
28 6572 274 17 34.20 48.10 45.00 1.50 567.50 568.37 487.51 80.86
29 7512 313 18 69.10 54.70 51.20 1.60 569.49 568.61 487.52 81.09
30 7286 304 17 50.30 53.70 50.00 1.60 569.02 568.74 487.78 80.96
TOT245696  557        
AVG 8190 341 19 60.12 60.49 56.85 1.79 569.08 568.88 488.08 80.80
MAX 13911   94.10 101.80 97.70 4.40 570.92 570.50 490.45 83.86
MIN 4400   33.80 33.40 29.80 1.00 566.55 566.48 485.71 79.03
BUILDING STRONG®