Bonneville Dam & Lake on Columbia River

March 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	18081	753	96	185.20	186.20	176.80	1.20	73.10	73.50	16.50	57.00	16.30	10632	104.80
2	18244	760	96	189.30	190.30	181.20	1.30	73.00	73.20	16.80	56.40	16.60	10776	108.00
3	17318	722	96	186.20	178.20	169.10	1.30	73.90	73.20	16.10	57.10	15.90	10507	103.50
4	17519	730	96	180.20	176.20	167.00	1.30	74.30	74.20	15.90	58.30	15.80	10424	100.40
5				180.50	181.50	172.40	1.30	74.20	74.10	16.20	57.90	16.00		114.30
6				180.90	173.90	164.60	1.40	74.90	74.50	15.70	58.80	15.60		90.30
7				178.20	175.20	166.10	1.30	75.10	75.00	15.60	59.40	15.50		97.90
8				186.50	187.50	178.20	1.30	75.00	74.90	16.40	58.50	16.20		104.00
9				201.80	195.80	184.90	1.40	75.70	75.70	16.90	58.80	16.80		107.50
10				185.00	193.00	181.70	1.40	75.00	75.20	16.70	58.50	16.60		105.20
11								73.70
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TOT	71162		384
AVG	17790	741	96	185.38	183.78	174.20	1.32	74.35	74.35	16.28	58.07	16.13	10585	103.59

MAX	18244			201.80	195.80	184.90	1.40	75.70	75.70	16.90	59.40	16.80	10776	114.30
MIN	17318			178.20	173.90	164.60	1.20	73.00	73.20	15.60	56.40	15.50	10424	90.30