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				119.00	117.00	31.10	73.50	76.10	76.00	11.10	64.90	11.00		31.10
4				122.00	125.00	31.10	81.50	75.80	75.60	11.50	64.10	11.40		31.10
5				124.00	124.00	30.80	80.80	75.70	75.50	11.40	64.10	11.40		30.80
6				129.90	129.90	33.10	84.40	75.70	75.20	11.90	63.30	11.90		26.50
7				127.50	125.50	33.80	79.30	76.00	75.60	11.60	64.00	11.70		19.40
8				123.80	123.80	31.00	80.40	75.80	75.60	11.70	63.90	11.70		31.00
9				123.00	122.00	31.10	78.50	76.10	75.60	11.70	63.90	11.60		31.10
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TOT	7109		192
AVG	3554	148	96	123.57	123.68	31.62	79.66	75.91	75.62	11.57	64.06	11.54	3554	29.29

MAX	3583			129.90	129.90	33.80	84.40	76.10	76.00	11.90	64.90	11.90	3583	31.50
MIN	3526			119.00	117.00	30.80	73.50	75.70	75.20	11.10	63.30	11.00	3526	19.40