San Gabriel
4 monitoring stations within this area in United States, holding 684 values between 1895 and 2026. A United States federal hydrologic unit at the eight-digit subbasin level — a drainage area, not a river. Many subbasins take the name of the largest river within them, and the gauges below are anywhere inside the area, including on tributaries.
The monitoring network within this area
Hydrionis holds 684 values from 4 gauges within it. Discharge is a property of a gauge and its reach, not of this drainage area, so this page reports the network and its records rather than a single figure.
Flood peaks, as measured
This gauge's flood record, as measured. Unlike a daily mean it is the discharge at the moment the river was highest, which is the figure flood frequency analysis is built on.
Published by the gauge's own operator from its sub-daily record; Hydrionis stores the figure rather than recomputing it. A year the gauge did not cover produces no value rather than a low one, and the gaps are stated below the chart. A peak is a property of this gauge and its reach: a larger flood upstream or downstream of it is not in this series.
What the shaded periods are (0 events)
View the data behind this chart
| Period | FISH C NR DUARTE CA (m³/s) |
|---|---|
| 1918 | 9.34 |
| 1919 | 0.595 |
| 1920 | 7.22 |
| 1921 | 8.10 |
| 1922 | 14.3 |
| 1924 | 1.64 |
| 1927 | 26.8 |
| 1928 | 2.75 |
| 1929 | 2.01 |
| 1930 | 2.04 |
| 1931 | 1.98 |
| 1933 | 8.47 |
| 1934 | 18.1 |
| 1935 | 11.9 |
| 1936 | 19.1 |
| 1938 | 59.5 |
| 1940 | 6.37 |
| 1941 | 12.5 |
| 1943 | 59.5 |
| 1944 | 19.3 |
| 1945 | 15.3 |
| 1946 | 11.3 |
| 1948 | 0.793 |
| 1949 | 0.991 |
| 1951 | 0.453 |
| 1952 | 38.5 |
| 1954 | 10.6 |
| 1955 | 1.10 |
| 1956 | 15.4 |
| 1957 | 3.06 |
| 1958 | 17.2 |
| 1959 | 56.6 |
| 1960 | 2.38 |
| 1962 | 21.8 |
| 1963 | 9.80 |
| 1964 | 5.04 |
| 1965 | 4.62 |
| 1966 | 47.3 |
| 1967 | 7.99 |
| 1969 | 368 |
| 1970 | 25.4 |
| 1971 | 1.81 |
| 1973 | 45.0 |
| 1974 | 10.6 |
| 1976 | 4.11 |
| 1978 | 37.9 |
| 1979 | 2.21 |
About this series
| Source | United States Geological Survey — National Water Information System · US Government work — public domain |
|---|---|
| How the values came to exist | Measured |
| Period held | 1918–1979 |
| Completeness | 75.8% of the periods in that span are held. Gaps are drawn as breaks and never interpolated. |
| Known gaps |
|
| Continuity | The record begins in 1918 and is not continuous from it: 62 years separate the first value from the last, and 76% of the years between them are held. The span is not the record. |
| Last read from the publisher | 2026-10-01 |
| Redistribution | Permitted by the upstream licences |
| Commercial reuse | Permitted by the upstream licences. No Hydrionis access tier can widen this. |
| Methodology | How this was produced |
How much of the rain came back out
A discharge in cubic metres per second cannot be compared with anything: the larger number may only mean the larger catchment. Divided by the area draining to the gauge it becomes a depth of water over that land, which answers a question a reader already has — of the rain that fell here, how much came back out as river?
Computed by Hydrionis from the published annual mean flow and the catchment area the station's own publisher states. It is not a water balance: the difference between rainfall and runoff is not evaporation alone but also change in groundwater storage, water abstracted and taken elsewhere, and water imported by transfer schemes — which is why a catchment can yield more runoff than the rain that fell on it without anything being measured wrongly. A different area figure rescales every value here by the ratio between them.
What the shaded periods are (0 events)
View the data behind this chart
| Period | SAN GABRIEL R NR AZUSA CA (mm) |
|---|---|
| 1896 | 17.0 |
| 1897 | 163 |
| 1898 | 4.00 |
| 1899 | 0 |
| 1900 | 23.0 |
| 1901 | 129 |
| 1902 | 7.00 |
| 1903 | 167 |
| 1904 | 15.0 |
| 1905 | 277 |
| 1906 | 422 |
| 1907 | 654 |
| 1908 | 75.0 |
| 1909 | 318 |
| 1910 | 184 |
| 1911 | 525 |
| 1912 | 90.0 |
| 1913 | 42.0 |
| 1914 | 579 |
| 1915 | 172 |
| 1916 | 533 |
| 1917 | 55.0 |
| 1918 | 198 |
| 1919 | 6.00 |
| 1920 | 151 |
| 1921 | 323 |
| 1922 | 596 |
| 1923 | 30.0 |
| 1924 | 6.00 |
| 1925 | 7.00 |
| 1926 | 184 |
| 1927 | 195 |
| 1928 | 7.00 |
| 1929 | 16.0 |
| 1930 | 35.0 |
| 1931 | 26.0 |
| 1932 | 183 |
| 1933 | 38.0 |
| 1934 | 63.0 |
| 1935 | 151 |
| 1936 | 54.0 |
| 1937 | 311 |
| 1938 | 692 |
| 1939 | 81.0 |
| 1940 | 60.0 |
| 1941 | 519 |
| 1942 | 17.0 |
| 1943 | 539 |
| 1944 | 296 |
| 1945 | 125 |
| 1946 | 189 |
| 1947 | 27.0 |
| 1948 | 32.0 |
| 1949 | 6.00 |
| 1950 | 0 |
| 1951 | 17.0 |
| 1952 | 255 |
| 1953 | 4.00 |
| 1954 | 53.0 |
| 1955 | 0 |
| 1956 | 8.00 |
| 1957 | 13.0 |
| 1958 | 387 |
| 1959 | 0 |
| 1960 | 0 |
| 1961 | 4.00 |
| 1962 | 163 |
| 1963 | 2.00 |
| 1964 | 2.00 |
| 1965 | 193 |
About this series
| Source | United States Geological Survey — National Water Information System · US Government work — public domain |
|---|---|
| How the values came to exist | Derived Computed by Hydrionis |
| Period held | 1896–1965 |
| Completeness | 100.0% of the periods in that span are held. |
| Continuity | Continuous: every year from 1896 to 1965 is held. |
| Inputs last read | 2026-10-01 · when the records this was computed from were last read from their publishers |
| Calculation date | 2026-08-24 · when the calculation method was last versioned, not a reading of any publisher |
| Redistribution | Permitted by the upstream licences |
| Commercial reuse | Permitted by the upstream licences. No Hydrionis access tier can widen this. |
| Methodology | How this was produced |
Every gauge Hydrionis holds within this area
| Gauge | Measures | Values | Record |
|---|---|---|---|
| SAN GABRIEL R NR AZUSA CA | burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year | 228 | 1895–2026 |
| FISH C NR DUARTE CA | burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year | 218 | 1917–2026 |
| WF SAN GABRIEL R A CAMP RINCON CA | burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year | 189 | 1927–2026 |
| SAN GABRIEL R A PICO CA | catchment area, annual maximum river flow | 49 | 1929–2026 |
How these gauges were attached to this water
Assigned by the publisher to a numbered basin Every gauge here is assigned to this drainage area by its own publisher, which issues the area an official code — 18070106. A drainage area is not a river: it contains the tributaries as well as the main channel, and a gauge in it may be on any of them.
| Gauge | Evidence | Established |
|---|---|---|
| SAN GABRIEL R NR AZUSA CA | Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4 | 2026-10-02 |
| FISH C NR DUARTE CA | Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4 | 2026-10-02 |
| WF SAN GABRIEL R A CAMP RINCON CA | Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4 | 2026-10-02 |
| SAN GABRIEL R A PICO CA | Stated by the publisher — USGS site service, huc_cd field — https://waterservices.usgs.gov/nwis/site/ ; named from the USGS Watershed Boundary Dataset 8-digit HU (Subbasin) layer — https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer/4 | 2026-10-02 |
What this record holds
Hydrionis decides which waters get a page, and which of those are offered to search, from what is actually held rather than from how the page reads. Five signals are counted; this record has 4 of them, which makes it a full profile.
| Signal | Held | Counts |
|---|---|---|
| Gauges holding a real record | 3 | yes, 3 or more |
| Years spanned | 132 | yes, 20 or more |
| Values held | 684 | no |
| Distinct measurements | 5 | yes, 2 or more |
| Publishers measuring it | 2 | yes, 2 or more |
| Official identifiers | 1 | recorded, not counted |
Use this data
Use this data
- Machine-readable JSON
/api/v1/observations/by-subject/gauge-usgs-11083500.json - How to cite this, and who you must credit
- How these figures were produced
- Request this at a different scale, format or geography
Attribution and citation
Suggested citation for Hydrionis
Hydrionis (2026), San Gabriel gauge records, accessed 2026-10-05, hydrionis.com/waters/united-states-san-gabriel/
Cite Hydrionis where you rely on values Hydrionis computed, on the method that produced them, or on the compilation itself. The underlying measurements remain the publishers’ and their attribution requirements apply to you directly.
Where these figures come from
Source: USGS — National Water Information System, USGS site 11083500, annual peak streamflow. Licence: Open.
Method: The instantaneous maximum discharge of each water year as published by USGS, dated to the day it occurred. One value per October-to-September water year; where the publisher lists both a systematic and a historic peak for a year, the larger is the annual maximum. Values the publisher marks as maximum daily averages are not held here, because they are not instantaneous peaks. Values marked as bounded rather than measured are held as censored observations carrying the bound. Cubic feet per second are converted to cubic metres per second and the publisher unit is recorded alongside.
Rating curves are extrapolated at extreme discharges, so the largest values in a peak series carry the largest measurement uncertainty. Data from the U.S. Geological Survey National Water Information System, a work of the United States government and therefore in the public domain.
Retrieved 1 October 2026.