Lower Granite Bypass and Spillway Analyses

Data Courtesy of U.S. Army Corps of Engineers, NWD and Pacific States Marine Fisheries Commission

PIT Tag Lower Granite Bypass and Spillway Queries

Lower Granite Bypass and Spillway Juvenile and Adult Daily Summary

Last Update: March 30 2026 07:25:02.

2026 Lower Granite Spillway (GRS) and Bypass (GRJ) Juvenile and Adult Daily Detection Summary
Water and Fish daily averages and totals calculated from hourly timestamps in Pacific Time with daylight savings
Calendar Date	Spill Conditions					Juveniles								Adults
	Outflow (daily avg) kcfs	Spill (daily avg) kcfs	Spill Hours All Bays	Spill Hours Spillbay 1	Percent Spill in Spillbay 1	Chinook		Steelhead		Coho		Sockeye		Chinook		Steelhead		Coho		Sockeye
	Outflow (daily avg) kcfs	Spill (daily avg) kcfs	Spill Hours All Bays	Spill Hours Spillbay 1	Percent Spill in Spillbay 1	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)
Calendar Date	Spill Conditions					Juveniles								Adults
	Outflow (daily avg) kcfs	Spill (daily avg) kcfs	Spill Hours All Bays	Spill Hours Spillbay 1	Percent Spill in Spillbay 1	Chinook		Steelhead		Coho		Sockeye		Chinook		Steelhead		Coho		Sockeye
	Outflow (daily avg) kcfs	Spill (daily avg) kcfs	Spill Hours All Bays	Spill Hours Spillbay 1	Percent Spill in Spillbay 1	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)	Spillway (GRS)	Bypass (GRJ)
YTD Total						826	1377	460	592	24	14					132	32
2026-03-29	72.3	9.6	24	24	100.0	243	325	351	386	21	8					7	4
2026-03-28	76.2	9.0	24	24	100.0	120	299	55	124	3	2					5	3
2026-03-27	84.4	9.1	24	24	100.0	85	184	24	16		2					7	2
2026-03-26	76.3	9.6	24	24	99.9	28	163	5	6		2					4	3
2026-03-25	67.1	8.8	24	24	100.0	81	173	3	6							5	4
2026-03-24	67.7	9.3	24	24	100.2	115	95	10	5							5
2026-03-23	69.9	8.8	24	24	100.0	90	52	3	5							1
2026-03-22	75.9	9.3	24	24	100.0	41	46	4	4							3	1
2026-03-21	60.9	8.7	24	24	100.1	23	18	3	3							13
2026-03-20	61.1	0.0	1	1	22.0		13		8
2026-03-19	62.5	1.4	6	6	100.1		1		3							4
2026-03-18	61.1	0.0	0	0	0.0		2		7								1
2026-03-17	63.2	1.6	5	5	99.5		5	1	7							1	3
2026-03-16	66.6	0.0	0	0	0.0		1	1	2								1
2026-03-15	94.1	2.0	6	5	99.8				5							2	3
2026-03-14	92.3	0.0	0	0	0.0				3								3
2026-03-13	64.9	0.0	0	0	0.0				1
2026-03-12	48.9	2.1	6	5	100.4				1							3	2
2026-03-11	45.7	0.0	0	0	0.0
2026-03-10	39.2	1.9	6	5	100.5											11
2026-03-09	42.6	0.0	0	0	0.0
2026-03-08	38.4	2.0	5	5	100.1											16
2026-03-07	38.8	0.0	0	0	0.0
2026-03-06	40.7	0.0	0	0	0.0
2026-03-05	43.7	1.8	5	5	100.1											8
2026-03-04	34.7	0.0	0	0	0.0
2026-03-03	34.1	1.9	5	4	100.2											8
2026-03-02	34.3	0.0	0	0	0.0
2026-03-01	34.2	2.0	6	5	99.6											29
2026-02-28	42.1	0.0	0	0	0.0
2026-02-27	43.5	0.0	0	0	0.0
2026-02-26	43.3	0.0	0	0	0.0
2026-02-25	34.6	0.0	0	0	0.0
2026-02-24	36.1	0.0	0	0	0.0
2026-02-23	33.2	0.0	0	0	0.0
2026-02-22	27.8	0.0	0	0	0.0
2026-02-21	29.2	0.0	0	0	0.0
2026-02-20	32.0	0.0	0	0	0.0
2026-02-19	36.4	0.0	0	0	0.0
2026-02-18	27.2	0.0	0	0	0.0
2026-02-17	40.7	0.0	0	0	0.0
2026-02-16	30.7	0.0	0	0	0.0
2026-02-15	31.6	0.0	0	0	0.0
2026-02-14	33.7	0.0	0	0	0.0
2026-02-13	28.5	0.0	0	0	0.0
2026-02-12	30.6	0.0	0	0	0.0
2026-02-11	28.1	0.0	0	0	0.0
2026-02-10	31.5	0.0	0	0	0.0
2026-02-09	37.0	0.0	0	0	0.0
2026-02-08	29.7	0.0	0	0	0.0
2026-02-07	32.0	0.0	0	0	0.0
2026-02-06	26.9	0.0	0	0	0.0
2026-02-05	29.2	0.0	0	0	0.0
2026-02-04	26.7	0.0	0	0	0.0
2026-02-03	32.9	0.0	0	0	0.0
2026-02-02	30.8	0.0	0	0	0.0
2026-02-01	30.4	0.0	0	0	0.0
2026-01-31	34.4	0.0	0	0	0.0
2026-01-30	33.0	0.0	0	0	0.0
2026-01-29	30.7	0.0	0	0	0.0
2026-01-28	35.1	0.0	0	0	0.0
2026-01-27	35.1	0.0	0	0	0.0
2026-01-26	30.1	0.0	0	0	0.0
2026-01-25	34.9	0.0	0	0	0.0
2026-01-24	34.7	0.0	0	0	0.0
2026-01-23	35.5	0.0	0	0	0.0
2026-01-22	36.4	0.0	0	0	0.0
2026-01-21	40.9	0.0	0	0	0.0
2026-01-20	39.7	0.0	0	0	0.0
2026-01-19	40.4	0.0	0	0	0.0
2026-01-18	41.8	0.0	0	0	0.0
2026-01-17	41.7	0.0	0	0	0.0
2026-01-16	44.8	0.0	0	0	0.0
2026-01-15	42.6	0.0	0	0	0.0
2026-01-14	43.2	0.0	0	0	0.0
2026-01-13	45.0	0.1	2	2	57.8
2026-01-12	46.9	0.0	0	0	0.0
2026-01-11	43.1	0.0	0	0	0.0
2026-01-10	48.8	0.0	0	0	0.0
2026-01-09	51.2	0.0	0	0	0.0
2026-01-08	51.0	0.0	0	0	0.0
2026-01-07	45.8	0.0	0	0	0.0
2026-01-06	48.9	0.0	0	0	0.0
2026-01-05	51.4	0.0	0	0	0.0
2026-01-04	44.3	0.0	0	0	0.0
2026-01-03	46.7	0.0	0	0	0.0												1
2026-01-02	41.9	0.0	0	0	0.0												1
2026-01-01	40.4	0.0	0	0	0.0

Lower Granite Bypass and Spillway Juvenile Downstream Detections Summary by Species

Last Update: March 30 2026 07:25:02.

2026 Juvenile Chinook Downstream Detections
Fish daily totals calculated from hourly timestamps in Pacific Time with daylight savings
Calendar Date	Spillway and then Downstream, Unique TagIDs Detected							Bypass and then Downstream, Unique TagIDs Detected
Calendar Date	Spillway (GRS)	Little Goose	Lower Monumental	Ice Harbor	McNary	John Day	Bonneville	Bypass (GRJ)	Little Goose	Lower Monumental	Ice Harbor	McNary	John Day	Bonneville
YTD Total	826	48	9	7				1377	51	5	5
2026-03-29	243	22	3					325	22	2	1
2026-03-28	120	4	3	1				299	12	1	1
2026-03-27	85	4	2	4				184	6		1
2026-03-26	28	7	1	1				163	2
2026-03-25	81	5		1				173	6	1	2
2026-03-24	115	3						95	3	1
2026-03-23	90	3						52
2026-03-22	41							46
2026-03-21	23							18
2026-03-20								13
2026-03-19								1
2026-03-18								2
2026-03-17								5
2026-03-16								1

2026 Juvenile Steelhead Downstream Detections
Fish daily totals calculated from hourly timestamps in Pacific Time with daylight savings
Calendar Date	Spillway and then Downstream, Unique TagIDs Detected							Bypass and then Downstream, Unique TagIDs Detected
Calendar Date	Spillway (GRS)	Little Goose	Lower Monumental	Ice Harbor	McNary	John Day	Bonneville	Bypass (GRJ)	Little Goose	Lower Monumental	Ice Harbor	McNary	John Day	Bonneville
YTD Total	460	7	3	1				592	21	18	9
2026-03-29	351		1					386	2		3
2026-03-28	55		1	1				124		2	3
2026-03-27	24	4						16	1	7	1
2026-03-26	5	2						6	1	3	2
2026-03-25	3		1					6	1	2
2026-03-24	10	1						5	3	1
2026-03-23	3							5	6	1
2026-03-22	4							4	1
2026-03-21	3							3	3
2026-03-20								8	2
2026-03-19								3		1
2026-03-18								7
2026-03-17	1							7	1	1
2026-03-16	1							2
2026-03-15								5
2026-03-14								3
2026-03-13								1
2026-03-12								1

2026 Juvenile Coho Downstream Detections
Fish daily totals calculated from hourly timestamps in Pacific Time with daylight savings
Calendar Date	Spillway and then Downstream, Unique TagIDs Detected							Bypass and then Downstream, Unique TagIDs Detected
Calendar Date	Spillway (GRS)	Little Goose	Lower Monumental	Ice Harbor	McNary	John Day	Bonneville	Bypass (GRJ)	Little Goose	Lower Monumental	Ice Harbor	McNary	John Day	Bonneville
YTD Total	24							14
2026-03-29	21							8
2026-03-28	3							2
2026-03-27								2
2026-03-26								2

Query Notes

DART PIT Tag and ESU Metadata & Glossary