Lower Granite Dam & Lake

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	Midnight Lewiston Gage ft
1	26.60	26.90	12.50	14.00	735.74	735.82	633.94	101.88	736.30
2	25.90	27.20	13.00	13.60	735.43	735.57	633.82	101.75	735.87
3	24.50	24.30	13.00	10.70	735.49	735.38	633.51	101.87	735.87
4	27.60	27.10	12.70	13.90	735.62	735.61	633.84	101.77	736.01
5	28.40	28.60	12.60	15.40	735.55	735.63	634.25	101.38	735.94
6	29.70	29.70	12.50	16.70	735.55	735.57	634.06	101.51	735.92
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TOT
AVG	27.12	27.30	12.72	14.05	735.56	735.60	633.90	101.69	735.99

MAX	29.70	29.70	13.00	16.70	735.74	735.82	634.25	101.88	736.30
MIN	24.50	24.30	12.50	10.70	735.43	735.38	633.51	101.38	735.87