USGS Streamgage 13135520
NF Big Wood River near Sawtooth Nra Hq near Ketchum, ID
NF Big Wood River near Sawtooth Nra Hq near Ketchum, ID is USGS streamgage 13135520 in Idaho, monitoring river discharge in hydrologic subbasin 17040219. It drains a watershed of about 40 square miles. Discharge records at this site go back to 2011. Typical flow runs near 65.6 cfs in July and 38.8 cfs in April, with the higher of the two arriving in July. Rivermatics issues a daily machine-learned flow outlook for this gauge, reaching 14 days ahead.
View live conditions & forecast →
Gauge details
- State
- Idaho
- Drainage area
- 40 sq mi
- Subbasin (HUC-8)
- 17040219
- Coordinates
- 43.78611, -114.41917
- USGS site number
- 13135520
- Records begin
- 2011-04-19 (15 years)
- Rivermatics forecast
- 14-day flow outlook
14-day flow forecast
Based on observations through for NF Big Wood River near Sawtooth Nra Hq near Ketchum, ID. Each day carries a median estimate and the band the model expects the flow to fall within — not a single number to plan against. Forecasts are re-issued daily; see the live screen for the current outlook.
| Date | Low p10 | Expected p50 | High p90 | Range |
|---|---|---|---|---|
| 20.5 | 21.5 | 22.4 | ||
| 20.1 | 21.3 | 22.3 | ||
| 19.7 | 21 | 22.1 | ||
| 19.4 | 20.8 | 22 | ||
| 19.1 | 20.5 | 21.8 | ||
| 19.2 | 20.7 | 22.3 | ||
| 19.1 | 20.7 | 22.4 | ||
| 18.8 | 20.4 | 21.9 | ||
| 18.5 | 20 | 21.5 | ||
| 18.1 | 19.7 | 21.1 | ||
| 17.9 | 19.4 | 20.9 | ||
| 17.7 | 19.2 | 20.8 | ||
| 17.4 | 19 | 20.5 | ||
| 17.2 | 18.8 | 20.3 |
All values in cubic feet per second (cfs). Estimates only — do not use them for navigation or for any safety, rescue, or emergency decision.
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 15 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 | 11.2 | 15 | 19.3 | |
| February | 10.8 | 13.6 | 18.7 | |
| March | 11.9 | 15.5 | 36.6 | |
| April | 19.8 | 38.8 | 97.8 | |
| May | 60.4 | 126.5 | 333.1 | |
| June | 86.8 | 177.2 | 520 | |
| July | 37 | 65.6 | 237.7 | |
| August | 23.6 | 31.7 | 73.7 | |
| September | 18.1 | 23.8 | 40.9 | |
| October | 16.5 | 23 | 33.5 | |
| November | 13.8 | 19.5 | 29.4 | |
| December | 12 | 16.3 | 22.3 |
All values in cubic feet per second (cfs).
Common questions
- When does NF Big Wood River near Sawtooth Nra Hq near Ketchum, ID normally run highest?
- June, on the long-term record. The median daily flow that month is about 177.2 cfs, against 13.6 cfs in February, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for NF Big Wood River near Sawtooth Nra Hq near Ketchum, ID?
- It depends on the month. In January, half of days historically fall near 15 cfs, with the middle 80% of days between 11.2 and 19.3 cfs. The month-by-month table on this page gives the full range.
- How long has NF Big Wood River near Sawtooth Nra Hq near Ketchum, ID been measured?
- Discharge records at USGS site 13135520 begin in 2011, about 15 years, covering roughly 5,588 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Is there a flow forecast for NF Big Wood River near Sawtooth Nra Hq near Ketchum, ID?
- Yes. Rivermatics trains a machine-learned model — a temporal-fusion transformer — on this basin's observed flows, weather, and snowpack, and issues a daily flow outlook reaching 14 days ahead: a median estimate inside a confidence band, not a single number to bet on. Every forecast is scored against days the model never trained on, and that track record is published on the live gauge screen. Open live conditions to see the current outlook.
- Where is NF Big Wood River near Sawtooth Nra Hq near Ketchum, ID?
- The gauge sits at 43.78611, -114.41917, in Idaho, in hydrologic subbasin 17040219, draining roughly 40 square miles.
- Can I use NF Big Wood River near Sawtooth Nra Hq near Ketchum, ID data for flood or safety decisions?
- No. Rivermatics provides estimates, not guarantees, and the readings and forecasts here may be delayed, inaccurate, or wrong. Do not use them for navigation or for any safety, rescue, or emergency decision. Check the National Weather Service and USGS directly, and use your own judgment.