John Day & Lake Umatilla

August 2026

Day of Month	Inflow kcfs	Total Outflow kcfs	Generation Flow kcfs	Spill kcfs	Midnight Reservoir Elevation	Average Forebay Elevation	Average Tailwater Elevation	Average Head feet
1	131.50	126.50	83.10	42.10	263.62	263.47	160.34	103.13
2	134.20	124.40	78.90	44.10	264.02	263.85	160.35	103.50
3	117.10	122.00	77.60	42.90	263.52	263.91	160.39	103.52
4	118.60	121.10	77.00	42.90	263.72	263.67	159.91	103.76
5	133.70	128.80	84.30	43.00	263.91	263.76	160.18	103.58
6	130.50	132.90	86.70	45.10	263.82	263.90	160.40	103.50
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TOT
AVG	127.60	125.95	81.27	43.35	263.77	263.76	160.26	103.50

MAX	134.20	132.90	86.70	45.10	264.02	263.91	160.40	103.76
MIN	117.10	121.10	77.00	42.10	263.52	263.47	159.91	103.13