Bonneville Dam & Lake on Columbia River

August 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	3526	147	96	120.70	122.70	31.10	79.20	76.00	75.70	11.60	64.10	11.60	3526	31.10
2	3583	149	96	122.20	123.20	31.50	79.30	76.00	75.80	11.60	64.20	11.60	3583	31.50
3	3577	149	96	119.00	117.00	31.10	73.50	76.10	76.00	11.10	64.90	11.00	3577	31.10
4	3530	147	96	122.00	125.00	31.10	81.50	75.80	75.60	11.50	64.10	11.40	3530	31.10
5	3508	146	96	124.00	124.00	30.80	80.80	75.70	75.50	11.40	64.10	11.40	3508	30.80
6	3730	155	96	129.90	129.90	33.10	84.40	75.70	75.20	11.90	63.30	11.90	2960	26.50
7	3853	161	96	127.50	125.50	33.80	79.30	76.00	75.60	11.60	64.00	11.70	2169	19.40
8	3511	146	96	123.80	123.80	31.00	80.40	75.80	75.60	11.70	63.90	11.70	3513	31.00
9	3521	147	96	123.00	122.00	31.10	78.50	76.10	75.60	11.70	63.90	11.60	3521	31.10
10				114.20	119.20	31.20	75.60	75.60	75.60	11.50	64.10	11.40		31.20
11				116.70	118.70	31.10	75.20	75.30	75.20	11.40	63.80	11.40		31.10
12				117.00	109.00	31.80	64.80	76.20	75.40	10.90	64.50	10.80		31.80
13				113.10	113.10	31.80	68.90	76.20	76.00	11.10	64.90	11.10		31.80
14				111.10	114.10	31.60	70.10	75.90	75.90	11.30	64.60	11.30		31.60
15				119.20	114.20	31.60	70.20	76.50	75.70	11.30	64.40	11.20		31.60
16				111.60	118.60	31.90	74.30	75.70	75.80	11.50	64.30	11.50		31.90
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TOT	32339		864
AVG	3593	150	96	119.69	120.00	31.60	76.00	75.91	75.64	11.44	64.19	11.41	3321	30.29

MAX	3853			129.90	129.90	33.80	84.40	76.50	76.00	11.90	64.90	11.90	3583	31.90
MIN	3508			111.10	109.00	30.80	64.80	75.30	75.20	10.90	63.30	10.80	2169	19.40