Grand Coulee Dam

September 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	Banks Lake Elev
1	72.40	72.60	72.50	0.10	1276.70	1276.78	958.13	318.65	1564.46
2	73.60	66.60	66.60	0.10	1276.70	1276.64	957.35	319.29	1564.87
3	73.40	51.00	50.90	0.10	1277.00	1276.76	956.25	320.51	1565.20
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TOT
AVG	73.13	63.40	63.33	0.10	1276.80	1276.73	957.24	319.48	1564.84

MAX	73.60	72.60	72.50	0.10	1277.00	1276.78	958.13	320.51	1565.20
MIN	72.40	51.00	50.90	0.10	1276.70	1276.64	956.25	318.65	1564.46