John Day & Lake Umatilla

September 2026

Day of Month	Total Generation MWh	Average Generation MW	Station Use MWh	Inflow kcfs	Total Outflow kcfs	Generation Flow kcfs	Spill kcfs	Midnight Reservoir Elevation	Average Forebay Elevation	Average Tailwater Elevation	Average Head feet
1	13100	546	41	97.70	87.80	71.60	15.00	263.62	263.28	160.44	102.84
2	14871	620	41	101.70	86.50	80.50	4.80	264.21	264.12	160.47	103.65
3	15236	635	42	95.70	85.20	82.40	1.60	264.62	264.44	160.90	103.54
4	16333	681	41	91.00	91.00	88.20	1.60	264.62		160.96
5	12890	537	40	71.90	71.90	69.10	1.60	264.62	264.60	160.39	104.21
6				79.40	68.90	66.10	1.60	265.02	264.97	160.30	104.67
7				67.50	65.00	62.10	1.60	265.12	265.02	160.60	104.42
8				79.40	74.20	71.50	1.60	265.32	265.26	160.66	104.60
9				72.70	75.40	72.40	1.60	265.22	265.15	160.62	104.53
10				83.30	78.10	75.40	1.60	265.42	265.37	160.66	104.71
11				72.70	67.40	64.60	1.60	265.62	265.58	160.24	105.34
12				66.80	69.40	66.80	1.60	265.52	265.51	160.33	105.18
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TOT	72431		205
AVG	14486	604	41	81.65	76.73	72.56	2.98	264.91	264.85	160.55	104.34

MAX	16333			101.70	91.00	88.20	15.00	265.62	265.58	160.96	105.34
MIN	12890			66.80	65.00	62.10	1.60	263.62	263.28	160.24	102.84