Bonneville Dam & Lake on Columbia River

July 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	8554	356	96	194.00	189.00	80.60	95.90	75.60	75.20	16.30	58.90	16.30	8206	77.40
2	8091	337	96	188.40	184.40	75.70	96.20	76.00	75.60	16.00	59.60	16.00	7763	72.70
3	6973	291	96	167.10	173.10	64.30	96.30	75.40	75.60	15.40	60.20	15.40	6973	64.30
4	6811	284	96	168.50	171.50	63.40	95.80	75.20	75.10	15.30	59.80	15.30	6811	63.40
5	5262	219	96	160.00	156.00	47.80	95.80	75.50	75.10	14.10	61.00	14.10	5262	47.80
6	7032	293	96	169.30	173.30	64.90	95.90	75.10	75.20	15.00	60.20	15.10	7032	64.90
7	6191	258	96	167.60	164.60	57.10	95.20	75.40	75.30	14.70	60.60	14.70	6191	57.10
8	3614	151	96	139.30	139.30	32.40	94.50	75.30	75.20	13.10	62.10	13.10	3614	32.40
9	3468	144	96	143.60	137.60	30.90	94.30	76.00	75.00	12.60	62.40	12.60	3468	30.90
10	4314	180	96	142.90	145.90	38.50	95.00	75.70	75.80	13.30	62.50	13.30	4314	38.50
11	3524	147	96	138.40	138.40	31.30	94.80	75.60	75.50	12.80	62.70	12.90	3524	31.30
12	3544	148	96	129.00	131.00	31.40	87.20	75.50	75.20	12.40	62.80	12.40	3544	31.40
13	3602	150	96	128.50	129.50	31.90	85.20	75.40	75.00	12.30	62.70	12.30	3602	31.90
14	3597	150	96	136.80	133.80	32.00	89.40	76.00	75.10	12.60	62.50	12.60	3597	32.00
15	3504	146	96	135.90	138.90	31.40	95.10	75.40	75.20	13.10	62.10	13.10	3504	31.40
16	3459	144	96	141.70	137.70	31.00	94.40	75.90	75.10	13.00	62.10	13.00	3459	31.00
17	3559	148	96	119.50	116.50	30.80	73.20	76.10	75.90	11.60	64.30	11.60	3559	30.80
18	3590	150	96	106.90	107.90	30.80	64.70	76.00	76.00	10.80	65.20	10.70	3590	30.80
19	3645	152	96	120.70	119.70	31.50	75.80	76.10	75.80	11.30	64.50	11.30	3645	31.50
20	3558	148	96	129.00	129.00	31.10	85.50	76.10	75.70	11.90	63.80	11.90	3558	31.10
21	3584	149	96	129.30	129.30	31.60	85.40	76.10	75.70	11.90	63.80	11.90	3584	31.60
22	4215	176	96	133.10	139.10	38.00	88.80	75.50	75.40	12.50	62.90	12.50	4215	38.00
23	3500	146	96	132.60	127.60	31.10	84.10	75.90	75.30	11.90	63.40	11.90	3500	31.10
24	4115	171	96	135.90	132.90	36.60	83.90	76.40	75.70	12.10	63.60	12.10	4115	36.60
25	3467	144	96	132.80	136.80	31.00	93.40	75.90	75.60	12.60	63.00	12.70	3467	31.00
26	3480	145	96	120.80	118.80	30.40	76.00	76.10	75.80	11.40	64.40	11.30	3480	30.40
27	3476	145	96	119.40	119.40	30.40	76.70	76.10	75.80	11.40	64.40	11.30	3476	30.40
28	3721	155	96	125.50	124.50	32.80	79.20	76.20	75.70	11.70	64.00	11.60	3721	32.80
29	3689	154	96	131.60	132.60	33.40	86.90	76.30	75.20	12.40	62.80	12.40	3689	33.40
30	3545	148	96	115.00	114.00	31.00	70.60	76.20	75.70	11.10	64.60	11.10	3545	31.00
31	3581	149	96	118.00	118.00	31.20	74.30	76.20	76.10	11.20	64.90	11.20	3581	31.20

TOT	136265		2976
AVG	4396	183	96	139.39	139.04	39.56	87.08	75.81	75.47	12.83	62.64	12.83	4374	39.36

MAX	8554			194.00	189.00	80.60	96.30	76.40	76.10	16.30	65.20	16.30	8206	77.40
MIN	3459			106.90	107.90	30.40	64.70	75.10	75.00	10.80	58.90	10.70	3459	30.40