Rivermatics

USGS Streamgage 11181000

San Lorenzo C A Hayward, CA

San Lorenzo C A Hayward, CA is USGS streamgage 11181000 in California, monitoring river discharge in hydrologic subbasin 18050004. It drains a watershed of about 38 square miles. Discharge records at this site go back to 1940. Typical flow runs near 0.7 cfs in July and 8.9 cfs in April, with the higher of the two arriving in April.

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Gauge details

State
California
Drainage area
38 sq mi
Gauge elevation
136 ft
Subbasin (HUC-8)
18050004
Coordinates
37.68549, -122.06441
USGS site number
11181000
Records begin
1940-02-27 (86 years)

Typical flow by month

Long-term daily discharge percentiles from the USGS record (up to 86 years of data), averaged within each month. These describe the historical normal range — they are not a forecast and not today's reading.

Historical monthly discharge percentiles in cubic feet per second
Month Low p10 Typical p50 High p90 Range
January 0.7 7.7 123.1
February 1.5 14.2 120.9
March 2.2 14.7 95.3
April 1.7 8.9 47.6
May 0.6 3.9 13.5
June 0.1 1.6 6.5
July 0 0.7 2.7
August 0 0.3 1.7
September 0 0.2 1.5
October 0 0.4 3.2
November 0 0.9 7.3
December 0.3 2.4 45.2

All values in cubic feet per second (cfs).

Common questions

When does San Lorenzo C A Hayward, CA normally run highest?
March, on the long-term record. The median daily flow that month is about 14.7 cfs, against 0.2 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 San Lorenzo C A Hayward, CA?
It depends on the month. In January, half of days historically fall near 7.7 cfs, with the middle 80% of days between 0.7 and 123.1 cfs. The month-by-month table on this page gives the full range.
How long has San Lorenzo C A Hayward, CA been measured?
Discharge records at USGS site 11181000 begin in 1940, about 86 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 San Lorenzo C A Hayward, CA?
The gauge sits at 37.68549, -122.06441, in California, in hydrologic subbasin 18050004, at an elevation of about 136 feet, draining roughly 38 square miles.
Can I use San Lorenzo C A Hayward, 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.

Other gauges in this subbasin