McNary Dam & Lake Wallula

September 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
1	10549	440	120	102.20	96.00	82.50	8.80	338.03	337.91	264.25	73.66
2	9335	389	120	106.10	95.40	72.10	18.60	338.56	338.59	264.56	74.03
3	9038	377	120	99.80	92.80	69.50	18.60	338.93	338.88	264.68	74.20
4	8405	350	120	86.70		64.60		338.86	338.97	264.80	74.17
5				76.80	74.40	59.90	9.70	338.99	338.90	264.57	74.33
6				74.20	80.00	70.30	5.00	338.67	338.83	265.11	73.72
7				69.60	66.00	59.70	1.60	338.85	338.77	265.10	73.67
8				76.60	76.60	70.30	1.70	338.88	338.85	265.32	73.53
9				75.50	78.70	69.00	5.00	338.68	338.93	265.29	73.64
10				82.70	83.30	73.90	4.70	338.66	338.69	265.81	72.88
11				67.90	69.70	55.80	9.20	338.57	338.57	265.54	73.03
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TOT	37327		480
AVG	9332	389	120	83.46	81.29	67.96	8.29	338.70	338.72	265.00	73.71

MAX	10549			106.10	96.00	82.50	18.60	338.99	338.97	265.81	74.33
MIN	8405			67.90	66.00	55.80	1.60	338.03	337.91	264.25	72.88