USGS Streamgage 11530500
Klamath River near Klamath, CA
Klamath River near Klamath, CA is USGS streamgage 11530500 in California, monitoring river discharge in hydrologic subbasin 18010209. It drains a watershed of about 12,100 square miles. Discharge records at this site go back to 1861. Typical flow runs near 4,149.7 cfs in July and 22,280 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- California
- Drainage area
- 12,100 sq mi
- Gauge elevation
- 5 ft
- Subbasin (HUC-8)
- 18010209
- Coordinates
- 41.51093, -123.97948
- USGS site number
- 11530500
- Records begin
- 1861-12-01 (165 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 64 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 | 7,221.6 | 20,306.5 | 71,829 | |
| February | 9,390.3 | 22,396.6 | 66,444.8 | |
| March | 10,648.4 | 24,971 | 61,558.1 | |
| April | 9,848 | 22,280 | 45,813.3 | |
| May | 8,093.2 | 16,903.2 | 33,854.8 | |
| June | 4,644 | 9,191 | 19,653.3 | |
| July | 2,686.1 | 4,149.7 | 7,404.5 | |
| August | 2,077.7 | 2,943.2 | 4,297.4 | |
| September | 2,109.3 | 2,926.3 | 4,089 | |
| October | 2,378.7 | 3,525.5 | 6,942.6 | |
| November | 3,203 | 6,539.3 | 26,675.3 | |
| December | 4,741.3 | 13,675.8 | 61,096.8 |
All values in cubic feet per second (cfs).
Common questions
- When does Klamath River near Klamath, CA normally run highest?
- March, on the long-term record. The median daily flow that month is about 24,971 cfs, against 2,926.3 cfs in September, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Klamath River near Klamath, CA?
- It depends on the month. In January, half of days historically fall near 20,306.5 cfs, with the middle 80% of days between 7,221.6 and 71,829 cfs. The month-by-month table on this page gives the full range.
- How long has Klamath River near Klamath, CA been measured?
- Discharge records at USGS site 11530500 begin in 1861, about 165 years, covering roughly 9,126 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Where is Klamath River near Klamath, CA?
- The gauge sits at 41.51093, -123.97948, in California, in hydrologic subbasin 18010209, at an elevation of about 5 feet, draining roughly 12,100 square miles.
- Can I use Klamath River near Klamath, 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.