US Army Corps of Engineers

Wanapum Dam & Lake

December 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 14102 588 18 97.50 102.30 100.90 0.00 567.72 568.30 489.96 78.34
2 13674 570 17 97.50 99.50 98.10 0.00 567.43 568.13 489.74 78.39
3 13431 560 18 98.10 98.50 97.10 0.00 567.38 567.07 489.67 77.40
4 13004 542 17 105.60 94.50 93.10 0.00 568.93 567.33 489.29 78.04
5 17784 741 17 135.70 130.30 128.90 0.00 569.68 568.93 491.48 77.45
6 17201 717 16 113.50 126.50 125.10 0.00 567.88 568.65 491.30 77.35
7 14766 615 16 106.50 109.10 107.70 0.00 567.52 567.59 490.70 76.89
8 14424 601 16 115.20 105.50 104.10 0.00 568.87 568.47 490.50 77.97
9 14557 607 17 98.90 105.70 104.30 0.00 567.92 568.88 490.58 78.30
10 11563 482 17 95.40 83.20 81.80 0.00 569.60 568.59 489.50 79.09
11 13985 583 16 105.10 100.20 98.80 0.10 570.27 569.78 490.62 79.16
12 16665 694 16 111.00 119.90 118.40 0.10 569.04 569.95 491.43 78.52
13 16519 688 16 117.10 120.30 118.90 0.00 568.61 569.03 491.19 77.84
14 15665 653 16 118.40 114.00 112.60 0.00 569.21 568.75 490.93 77.82
15 15771 657 16 117.30 113.00 111.60 0.00 569.80 569.67 490.94 78.73
16 18935 789 16 143.30 137.80 136.40 0.00 570.55 570.27 492.30 77.97
17 20378 849 17 151.40 151.30 149.00 0.90 570.58 570.62 492.98 77.64
18 20656 861 17 159.50 155.40 150.20 3.80 571.13 570.98 493.31 77.67
19 121.10 144.00 140.70 1.90 567.98 569.03 492.43 76.60
20 139.70 126.00 124.60 0.00 569.87 569.60 491.55 78.05
21 150.40 152.90 151.50 0.00 569.52 569.78 492.92 76.86
22 159.60 147.90 146.50 0.00 571.12 569.96 492.62 77.34
23 149.60 153.40 152.00 0.00 570.59 570.38 492.98 77.40
24 148.20 145.10 139.20 4.50 571.02 570.59 492.68 77.91
25 136.90 144.70 143.30 0.00 569.96 570.22 492.50 77.72
26
27
28
29
30
31
TOT283080  299        
AVG 15727 655 17 123.70 123.24 121.39 0.45 569.29 569.22 491.36 77.86
MAX 20656   159.60 155.40 152.00 4.50 571.13 570.98 493.31 79.16
MIN 11563   95.40 83.20 81.80 0.00 567.38 567.07 489.29 76.60
BUILDING STRONG®