USGS Streamgage 11395030
SF Feather River below Little Grass Valley Dam, CA
SF Feather River below Little Grass Valley Dam, CA is USGS streamgage 11395030 in California, monitoring river discharge in hydrologic subbasin 18020123. It drains a watershed of about 26 square miles. Discharge records at this site go back to 1927. Typical flow runs near 58.3 cfs in July and 15.3 cfs in April, with the higher of the two arriving in July.
Gauge details
- State
- California
- Drainage area
- 26 sq mi
- Subbasin (HUC-8)
- 18020123
- Coordinates
- 39.72378, -121.02218
- USGS site number
- 11395030
- Records begin
- 1927-10-01 (99 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 98 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 | 5 | 11.6 | 216.7 | |
| February | 4.9 | 13 | 214 | |
| March | 5.7 | 18 | 253.5 | |
| April | 5.9 | 15.3 | 262.1 | |
| May | 8.4 | 61 | 385.2 | |
| June | 7.2 | 22.5 | 253.3 | |
| July | 5.7 | 58.3 | 201.1 | |
| August | 3.1 | 111.5 | 227.9 | |
| September | 2.9 | 124.1 | 331.2 | |
| October | 2.2 | 93.3 | 353.5 | |
| November | 3.7 | 11.7 | 203.5 | |
| December | 4.5 | 10.3 | 196.5 |
All values in cubic feet per second (cfs).
Common questions
- When does SF Feather River below Little Grass Valley Dam, CA normally run highest?
- September, on the long-term record. The median daily flow that month is about 124.1 cfs, against 10.3 cfs in December, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for SF Feather River below Little Grass Valley Dam, CA?
- It depends on the month. In January, half of days historically fall near 11.6 cfs, with the middle 80% of days between 5 and 216.7 cfs. The month-by-month table on this page gives the full range.
- How long has SF Feather River below Little Grass Valley Dam, CA been measured?
- Discharge records at USGS site 11395030 begin in 1927, about 99 years, covering roughly 8,821 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Where is SF Feather River below Little Grass Valley Dam, CA?
- The gauge sits at 39.72378, -121.02218, in California, in hydrologic subbasin 18020123, draining roughly 26 square miles.
- Can I use SF Feather River below Little Grass Valley Dam, CA 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.