Rivermatics

USGS Streamgage 11121900

Gibraltar Dam Diversion Weir A Gibraltar Dam, CA

Gibraltar Dam Diversion Weir A Gibraltar Dam, CA is USGS streamgage 11121900 in California, monitoring river discharge in hydrologic subbasin 18060010. Discharge records at this site go back to 1970. Typical flow runs near 7.9 cfs in July and 5.1 cfs in April, with the higher of the two arriving in July. Rivermatics issues a daily machine-learned flow outlook for this gauge, reaching 14 days ahead.

View live conditions & forecast →

Gauge details

State
California
Gauge elevation
1,229 ft
Subbasin (HUC-8)
18060010
Coordinates
34.52415, -119.68704
USGS site number
11121900
Records begin
1970-10-01 (56 years)
Rivermatics forecast
14-day flow outlook

14-day flow forecast

Based on observations through for Gibraltar Dam Diversion Weir A Gibraltar Dam, CA. Each day carries a median estimate and the band the model expects the flow to fall within — not a single number to plan against. Forecasts are re-issued daily; see the live screen for the current outlook.

Forecast daily mean discharge in cubic feet per second, by date
Date Low p10 Expected p50 High p90 Range
0 0.2 0.3
0 0.2 0.3
0 0.2 0.3
0 0.2 0.4
0 0.2 0.4
0 0.2 0.4
0 0.2 0.4
0 0.2 0.4
0 0.2 0.4
0 0.2 0.6
0 0.2 0.7
0 0.2 0.7
0 0.2 0.7
0 0.2 0.6

All values in cubic feet per second (cfs). Estimates only — do not use them for navigation or for any safety, rescue, or emergency decision.

Typical flow by month

Long-term daily discharge percentiles from the USGS record (up to 56 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 0.4 8.8
February 0 0.1 8
March 0 2.2 10.4
April 0 5.1 12.9
May 0 7.9 12.5
June 0 7.9 12.7
July 0 7.9 12.6
August 0 7.8 12
September 0 7.5 12.2
October 0 7 11.8
November 0 3.8 10.6
December 0 3.1 9.7

All values in cubic feet per second (cfs).

Common questions

When does Gibraltar Dam Diversion Weir A Gibraltar Dam, CA normally run highest?
May, on the long-term record. The median daily flow that month is about 7.9 cfs, against 0.1 cfs in February, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
What is a normal flow for Gibraltar Dam Diversion Weir A Gibraltar Dam, CA?
It depends on the month. In January, half of days historically fall near 0.4 cfs, with the middle 80% of days between 0 and 8.8 cfs. The month-by-month table on this page gives the full range.
How long has Gibraltar Dam Diversion Weir A Gibraltar Dam, CA been measured?
Discharge records at USGS site 11121900 begin in 1970, about 56 years, covering roughly 8,765 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
Is there a flow forecast for Gibraltar Dam Diversion Weir A Gibraltar Dam, CA?
Yes. Rivermatics trains a machine-learned model — a temporal-fusion transformer — on this basin's observed flows, weather, and snowpack, and issues a daily flow outlook reaching 14 days ahead: a median estimate inside a confidence band, not a single number to bet on. Every forecast is scored against days the model never trained on, and that track record is published on the live gauge screen. Open live conditions to see the current outlook.
Where is Gibraltar Dam Diversion Weir A Gibraltar Dam, CA?
The gauge sits at 34.52415, -119.68704, in California, in hydrologic subbasin 18060010, at an elevation of about 1,229 feet.
Can I use Gibraltar Dam Diversion Weir A Gibraltar Dam, 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