USGS Streamgage 12322000
Kootenai River at Porthill, ID
Kootenai River at Porthill, ID is USGS streamgage 12322000 in Idaho, monitoring river discharge in hydrologic subbasin 17010104. It drains a watershed of about 13,700 square miles. Discharge records at this site go back to 1894. Typical flow runs near 11,087.1 cfs in July and 12,786.7 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- Idaho
- Drainage area
- 13,700 sq mi
- Gauge elevation
- 1,766 ft
- Subbasin (HUC-8)
- 17010104
- Coordinates
- 48.99639, -116.5075
- USGS site number
- 12322000
- Records begin
- 1894-01-01 (132 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 13 years of data), averaged within each month. These describe the historical normal range — they are not a forecast and not today's reading.
| Month | Low p10 | Typical p50 | High p90 | Range |
|---|---|---|---|---|
| January | 4,967.7 | 6,571 | 22,125.8 | |
| February | 4,983.6 | 7,248.6 | 20,021.4 | |
| March | 5,713.5 | 9,414.2 | 25,977.4 | |
| April | 8,287 | 12,786.7 | 36,070 | |
| May | 18,658.1 | 29,435.5 | 41,745.2 | |
| June | 13,180.3 | 20,473.3 | 34,850 | |
| July | 8,011.6 | 11,087.1 | 19,919.4 | |
| August | 7,373.2 | 9,043.5 | 11,793.5 | |
| September | 6,505 | 7,646.7 | 9,715 | |
| October | 4,534.2 | 5,117.7 | 8,697.1 | |
| November | 5,498 | 13,550 | 23,860 | |
| December | 8,554.5 | 21,146.5 | 30,083.9 |
All values in cubic feet per second (cfs).