Bonneville Dam & Lake on Columbia River

October 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	Project Average Tailwater	2nd Powerhouse Total MWh	2nd Powerhouse Flow kcfs
1	7241	302	96	84.70	74.70	60.00	2.30	75.40	74.90	7.70	67.20	7.70	6883	57.00
2	7762	323	96	81.50	78.50	63.80	2.30	75.60	75.50	7.90	67.60	7.90	7646	62.90
3	7499	312	96	69.40	76.40	61.70	2.30	75.00	75.30	7.70	67.60	7.60	7399	60.90
4	8058	336	96	84.50	81.50	66.80	2.30	75.40	75.00	8.00	67.00	7.90	7754	64.40
5				84.60	84.60	69.90	2.30	75.30	75.00	8.30	66.70	8.30		64.70
6				91.20	92.20	77.50	2.30	75.20	74.90	8.90	66.00	8.90		66.50
7				99.80	100.80	86.10	2.30	75.10	74.90	9.60	65.30	9.60		65.80
8				105.90	102.90	88.10	2.40	75.40	75.00	9.90	65.10	10.10		69.80
9				88.60	88.60	73.80	2.40	75.60	75.40	9.10	66.30	9.30		65.60
10				84.00	85.00	70.20	2.40	75.40	75.30	8.80	66.50	8.90		65.20
11				81.40	79.40	64.60	2.40	75.50	75.30	8.60	66.70	8.50		64.60
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TOT	30560		384
AVG	7640	318	96	86.87	85.87	71.14	2.34	75.35	75.14	8.59	66.55	8.61	7420	64.31

MAX	8058			105.90	102.90	88.10	2.40	75.60	75.50	9.90	67.60	10.10	7754	69.80
MIN	7241			69.40	74.70	60.00	2.30	75.00	74.90	7.70	65.10	7.60	6883	57.00