US Army Corps of Engineers

Wanapum Dam & Lake

January 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 18542 773 18 142.40 139.50 138.10 0.00 569.03 567.94 492.15 75.79
2 19502 813 18 149.60 144.40 143.00 0.00 569.75 569.26 492.43 76.83
3 19740 822 17 146.50 147.20 145.80 0.00 569.65 569.32 492.79 76.53
4 18362 765 17 128.20 134.90 133.50 0.00 568.73 569.51 492.24 77.27
5 17429 726 17 133.40 130.40 129.00 0.00 569.13 567.86 491.73 76.13
6 19269 803 17 156.20 142.40 140.90 0.10 571.02 569.80 492.53 77.27
7 21176 882 17 167.20 167.80 156.70 9.80 570.94 570.90 493.86 77.04
8 20614 859 18 164.30 165.10 152.10 11.60 570.83 570.96 493.76 77.20
9 21440 893 17 154.30 161.70 160.30 0.00 569.81 570.19 493.44 76.75
10 19663 819 17 153.60 145.60 144.20 0.00 570.90 570.07 492.75 77.32
11 20646 860 17 154.50 151.70 150.30 0.00 571.28 570.99 493.20 77.79
12 20998 875 17 158.50 159.80 154.10 4.30 571.10 571.02 493.63 77.39
13 21876 912 18 163.10 164.90 162.10 1.40 570.86 570.84 493.65 77.19
14 20557 857 21 157.20 155.20 151.30 2.50 571.13 570.80 493.25 77.55
15 22225 926 21 164.60 169.70 164.80 3.50 570.42 570.92 493.97 76.95
16 22565 940 22 171.70 172.10 170.70 0.00 570.38 570.07 493.96 76.11
17 21502 896 23 165.60 160.20 158.80 0.00 571.12 570.71 493.55 77.16
18 22359 932 22 166.70 168.00 166.60 0.00 570.93 570.79 493.88 76.91
19 22496 937 22 168.20 169.50 168.10 0.00 570.76 570.77 493.94 76.83
20 21573 899 23 162.80 160.30 158.90 0.00 571.10 570.89 493.54 77.35
21 21932 914 22 163.80 163.20 161.80 0.00 571.17 571.02 493.71 77.31
22 152.40 156.50 155.10 0.00 570.62 570.82 493.35 77.47
23 147.80 150.30 148.90 0.00 570.27 570.16 492.81 77.35
24 157.20 150.60 149.20 0.00 571.17 570.67 492.83 77.84
25 158.10 159.20 157.80 0.00 571.03 570.95 493.41 77.54
26 162.40 175.80 174.30 0.00 569.19 570.05 494.29 75.76
27 155.60 158.10 156.70 0.00 568.84 568.66 493.25 75.41
28 139.50 151.80 150.40 0.10 567.12 567.77 493.08 74.69
29
30
31
TOT434466  401        
AVG 20689 862 19 155.91 156.28 153.70 1.19 570.30 570.13 493.25 76.88
MAX 22565   171.70 175.80 174.30 11.60 571.28 571.02 494.29 77.84
MIN 17429   128.20 130.40 129.00 0.00 567.12 567.77 491.73 74.69
BUILDING STRONG®