USGS Streamgage 11174600
Alamo Cn near Pleasanton, CA
Alamo Cn near Pleasanton, CA is USGS streamgage 11174600 in California, monitoring river discharge in hydrologic subbasin 18050004. It drains a watershed of about 40 square miles. Discharge records at this site go back to 1979. Typical flow runs near 2.1 cfs in July and 10.7 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- California
- Drainage area
- 40 sq mi
- Gauge elevation
- 307 ft
- Subbasin (HUC-8)
- 18050004
- Coordinates
- 37.69444, -121.91944
- USGS site number
- 11174600
- Records begin
- 1979-08-30 (47 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 47 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 | 3 | 10.8 | 328.6 | |
| February | 3.1 | 11.3 | 305.6 | |
| March | 3.2 | 15.2 | 189.6 | |
| April | 2.9 | 10.7 | 72.4 | |
| May | 1.9 | 4.2 | 24.2 | |
| June | 1.3 | 3 | 7.4 | |
| July | 0.7 | 2.1 | 5.2 | |
| August | 0.6 | 2.1 | 4.6 | |
| September | 0.6 | 2.3 | 6.4 | |
| October | 0.8 | 2.3 | 56.7 | |
| November | 1.3 | 3.8 | 56 | |
| December | 1.7 | 6.9 | 202 |
All values in cubic feet per second (cfs).
Common questions
- When does Alamo Cn near Pleasanton, CA normally run highest?
- March, on the long-term record. The median daily flow that month is about 15.2 cfs, against 2.1 cfs in July, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Alamo Cn near Pleasanton, CA?
- It depends on the month. In January, half of days historically fall near 10.8 cfs, with the middle 80% of days between 3 and 328.6 cfs. The month-by-month table on this page gives the full range.
- How long has Alamo Cn near Pleasanton, CA been measured?
- Discharge records at USGS site 11174600 begin in 1979, about 47 years, covering roughly 4,294 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Where is Alamo Cn near Pleasanton, CA?
- The gauge sits at 37.69444, -121.91944, in California, in hydrologic subbasin 18050004, at an elevation of about 307 feet, draining roughly 40 square miles.
- Can I use Alamo Cn near Pleasanton, 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.