USGS Streamgage 11051501
Santa Ana River near Mentone Cn + Cn, CA
Santa Ana River near Mentone Cn + Cn, CA is USGS streamgage 11051501 in California, monitoring river discharge in hydrologic subbasin 18070203. Discharge records at this site go back to 1912. Typical flow runs near 46.1 cfs in July and 70.8 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- California
- Subbasin (HUC-8)
- 18070203
- Coordinates
- 34.10834, -117.10059
- USGS site number
- 11051501
- Records begin
- 1912-03-01 (114 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 114 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 | 19.8 | 36.7 | 115.8 | |
| February | 21.4 | 48.7 | 204.5 | |
| March | 26.8 | 58 | 273.6 | |
| April | 29.7 | 70.8 | 286.3 | |
| May | 24.4 | 56.1 | 236.8 | |
| June | 16.7 | 47 | 163.4 | |
| July | 12.4 | 46.1 | 119.6 | |
| August | 12.9 | 44.2 | 95.1 | |
| September | 13.2 | 41.5 | 86.9 | |
| October | 15.3 | 38 | 79.8 | |
| November | 17.3 | 32.8 | 69.3 | |
| December | 18.6 | 33.2 | 76.5 |
All values in cubic feet per second (cfs).
Common questions
- When does Santa Ana River near Mentone Cn + Cn, CA normally run highest?
- April, on the long-term record. The median daily flow that month is about 70.8 cfs, against 32.8 cfs in November, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Santa Ana River near Mentone Cn + Cn, CA?
- It depends on the month. In January, half of days historically fall near 36.7 cfs, with the middle 80% of days between 19.8 and 115.8 cfs. The month-by-month table on this page gives the full range.
- How long has Santa Ana River near Mentone Cn + Cn, CA been measured?
- Discharge records at USGS site 11051501 begin in 1912, about 114 years, covering roughly 8,944 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Where is Santa Ana River near Mentone Cn + Cn, CA?
- The gauge sits at 34.10834, -117.10059, in California, in hydrologic subbasin 18070203.
- Can I use Santa Ana River near Mentone Cn + Cn, 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.