USGS Streamgage 11046325
San Mateo C A San Mateo Rd near San Onofre, CA
San Mateo C A San Mateo Rd near San Onofre, CA is USGS streamgage 11046325 in California, monitoring river discharge in hydrologic subbasin 18070301. It drains a watershed of about 93 square miles. Discharge records at this site go back to 2024. Typical flow runs near 0 cfs in July and 0 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- California
- Drainage area
- 93 sq mi
- Gauge elevation
- 133 ft
- Subbasin (HUC-8)
- 18070301
- Coordinates
- 33.41933, -117.53706
- USGS site number
- 11046325
- Records begin
- 2024-11-19 (2 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 2 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 | — | 0.1 | — | |
| February | — | 10.1 | — | |
| March | — | 1.9 | — | |
| April | — | 0 | — | |
| May | — | 0 | — | |
| June | — | 0 | — | |
| July | — | 0 | — | |
| August | — | 0 | — | |
| September | — | 0 | — | |
| October | — | 0 | — | |
| November | — | 0 | — | |
| December | — | 0 | — |
All values in cubic feet per second (cfs).
Common questions
- When does San Mateo C A San Mateo Rd near San Onofre, CA normally run highest?
- February, on the long-term record. The median daily flow that month is about 10.1 cfs, against 0 cfs in April, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- How long has San Mateo C A San Mateo Rd near San Onofre, CA been measured?
- Discharge records at USGS site 11046325 begin in 2024, about 2 years, covering roughly 620 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Where is San Mateo C A San Mateo Rd near San Onofre, CA?
- The gauge sits at 33.41933, -117.53706, in California, in hydrologic subbasin 18070301, at an elevation of about 133 feet, draining roughly 93 square miles.
- Can I use San Mateo C A San Mateo Rd near San Onofre, 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.