Largest rivers in Idaho by average flow
Active USGS stream gauges in Idaho, ranked by average flow. The Snake River at McDuff Rapids at China Garden ID gauge leads with 26,827 cfs.
| Rank | Name | Average flow |
|---|---|---|
| 1 | Snake River at McDuff Rapids at China Garden ID | 26,827 cfs |
| 2 | Pend Oreille River at Newport WA | 24,551 cfs |
| 3 | Clark Fork River below Cabinet Gorge Dam ID | 20,585 cfs |
| 4 | Snake River at Weiser ID | 16,987 cfs |
| 5 | Kootenai River Bel Moyie River near Bonners Ferry ID | 14,686 cfs |
| 6 | Clearwater River at Spalding ID | 14,301 cfs |
| 7 | Kootenai River at Porthill ID | 14,066 cfs |
| 8 | Clearwater River near Peck ID | 13,682 cfs |
| 9 | Kootenai River at Leonia, ID | 13,378 cfs |
| 10 | Snake River at Nyssa OR | 12,062 cfs |
| 11 | Salmon River at White Bird ID | 10,589 cfs |
| 12 | Snake River near Murphy ID | 10,273 cfs |
| 13 | Snake River at King Hill ID | 10,153 cfs |
| 14 | Snake River at Neeley ID | 7,323 cfs |
| 15 | Snake River near Heise ID | 6,847 cfs |
| 16 | Snake River near Irwin ID | 6,322 cfs |
| 17 | Snake River near Minidoka Id at Howells Ferry | 6,282 cfs |
| 18 | Spokane River near Post Falls, ID | 5,972 cfs |
| 19 | Snake River near Menan ID | 5,792 cfs |
| 20 | Snake River above Eagle Rock near Idaho Falls ID | 5,739 cfs |
| 21 | Snake River near Shelley ID | 5,713 cfs |
| 22 | Spokane River below Blackwell near Coeur D Alene ID | 5,475 cfs |
| 23 | Snake River near Blackfoot ID | 4,531 cfs |
| 24 | Snake River near Buhl ID | 4,517 cfs |
| 25 | Snake River at Blackfoot ID | 4,385 cfs |
| 26 | Snake River at Lorenzo ID | 3,963 cfs |
| 27 | Selway River near Lowell ID | 3,470 cfs |
| 28 | North Fork Clearwater River near Canyon Ranger Station ID | 3,173 cfs |
| 29 | Payette River near Horseshoe Bend ID | 3,065 cfs |
| 30 | Snake River near Twin Falls ID | 3,009 cfs |
How the Average flow figures spread in Idaho
- The ranking covers the 187 gauges in Idaho that have a recorded average flow in this dataset.
- The highest is Snake River at McDuff Rapids at China Garden ID at 26,827 cfs; the lowest is Big Timber Creek Abv Mouth at Leadore ID at 5.6 cfs.
- The median average flow is 299 cfs.
- The gap between #1 Snake River at McDuff Rapids at China Garden ID and #2 Pend Oreille River at Newport WA is 2,276 cfs.
- The page table lists the top 30.
Data: U.S. Geological Survey (USGS) (public domain, U.S. federal data).· Updated 2026-11-02 · Text generated from the data and checked against it.
Live values are provisional USGS data. Measurements only, not a safety assessment — for flood warnings see the National Weather Service.