US Army Corps of Engineers

John Day & Lake Umatilla

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 40526 1689 50 231.70 232.10 221.10 9.80 265.52 265.52 162.87 102.65
2 36634 1526 53 214.40 209.10 198.30 9.80 265.72 265.46 161.88 103.58
3 36952 1540 52 213.80 211.20 200.10 9.80 265.82 265.86 162.37 103.49
4 35992 1500 49 209.10 206.50 195.20 9.80 265.92 265.95 162.57 103.38
5 36790 1533 48 208.60 211.20 200.00 9.80 265.82 265.91 162.84 103.07
6 35712 1488 46 193.70 204.10 193.10 9.80 265.42 265.67 162.09 103.58
7 33984 1416 44 186.40 194.20 183.50 9.70 265.12 265.08 161.46 103.62
8 30815 1284 44 181.50 176.30 165.20 9.70 265.32 265.25 160.94 104.31
9 31022 1293 44 178.20 178.20 166.60 10.50 265.32 265.48 161.43 104.05
10 12251 510 40 184.20 184.20 64.90 118.00 265.32 265.40 160.35 105.05
11 11306 471 40 199.30 199.30 60.20 137.70 265.32 265.28 160.95 104.33
12 11337 472 40 205.70 216.20 60.60 154.30 264.92 265.16 161.19 103.97
13 11345 473 43 211.30 211.30 60.70 149.30 264.92 264.83 160.89 103.94
14 11300 471 44 222.30 211.90 60.50 150.20 265.32 265.14 161.10 104.04
15 11360 473 46 212.20 212.20 60.70 150.30 265.32 265.20 161.17 104.03
16 11342 473 50 225.20 212.10 60.40 150.50 265.82 265.53 161.17 104.36
17 11479 478 48 232.60 235.30 61.20 172.90 265.72 265.73 161.47 104.26
18 11399 475 47 234.00 241.80 60.70 179.70 265.42 265.59 161.16 104.43
19 11523 480 46 214.20 216.80 61.90 153.70 265.32 265.40 161.37 104.03
20 11521 480 47 221.30 216.10 61.80 153.00 265.52 265.37 160.85 104.52
21 11558 482 46 221.70 221.60 61.70 158.70 265.52 265.52 160.53 104.99
22 11265 469 50 219.80 217.20 60.50 155.50 265.62 265.36 161.59 103.77
23 11322 472 48 251.60 241.10 60.50 179.20 266.02 265.74 161.75 103.99
24 11407 475 50 235.60 259.10 61.10 196.60 265.12 265.37 161.53 103.84
25 11413 476 48 255.50 247.70 60.90 185.40 265.42 265.25 161.08 104.17
26 11522 480 47 249.40 241.50 61.30 179.00 265.72 265.60 161.14 104.46
27 11507 479 46 233.80 239.00 62.00 175.80 265.52 265.64 161.62 104.02
28 11418 476 47 229.80 227.20 61.60 164.50 265.62 265.59 161.59 104.00
29 11421 476 46 225.90 231.10 61.60 168.00 265.42 265.54 161.66 103.88
30 11426 476 46 230.30 238.10 61.60 175.30 265.12 265.28 161.26 104.02
TOT558848  1395        
AVG 18628 776 47 217.77 218.12 100.32 116.54 265.47 265.46 161.46 103.99
MAX 40526   255.50 259.10 221.10 196.60 266.02 265.95 162.87 105.05
MIN 11265   178.20 176.30 60.20 9.70 264.92 264.83 160.35 102.65
BUILDING STRONG®