USGS Streamgage 11023340
Los Penasquitos C near Poway, CA
Los Penasquitos C near Poway, CA is USGS streamgage 11023340 in California, monitoring river discharge in hydrologic subbasin 18070304. It drains a watershed of about 42 square miles. Discharge records at this site go back to 1964. Typical flow runs near 1.2 cfs in July and 3.8 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- California
- Drainage area
- 42 sq mi
- Gauge elevation
- 255 ft
- Subbasin (HUC-8)
- 18070304
- Coordinates
- 32.9431, -117.1217
- USGS site number
- 11023340
- Records begin
- 1964-10-01 (62 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 62 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 | 1 | 3 | 49.4 | |
| February | 1.4 | 4.4 | 87.4 | |
| March | 1.4 | 5.3 | 65.3 | |
| April | 1.2 | 3.8 | 19.7 | |
| May | 0.6 | 2.3 | 7.7 | |
| June | 0.3 | 1.5 | 3.1 | |
| July | 0.2 | 1.2 | 2.6 | |
| August | 0.3 | 1.1 | 2.4 | |
| September | 0.3 | 1.2 | 2.7 | |
| October | 0.3 | 1.4 | 4.1 | |
| November | 0.4 | 1.9 | 15.5 | |
| December | 0.5 | 2.5 | 29 |
All values in cubic feet per second (cfs).
Common questions
- When does Los Penasquitos C near Poway, CA normally run highest?
- March, on the long-term record. The median daily flow that month is about 5.3 cfs, against 1.1 cfs in August, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Los Penasquitos C near Poway, CA?
- It depends on the month. In January, half of days historically fall near 3 cfs, with the middle 80% of days between 1 and 49.4 cfs. The month-by-month table on this page gives the full range.
- How long has Los Penasquitos C near Poway, CA been measured?
- Discharge records at USGS site 11023340 begin in 1964, about 62 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 Los Penasquitos C near Poway, CA?
- The gauge sits at 32.9431, -117.1217, in California, in hydrologic subbasin 18070304, at an elevation of about 255 feet, draining roughly 42 square miles.
- Can I use Los Penasquitos C near Poway, 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.