The monitoring network within this area

Hydrionis holds 507 values from 2 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.

Gauges

507

Values held

1910–2026

Record spans

Gauges within the Upper Eel huc8 subbasin

2 monitoring points, positioned as the publisher records them.

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.

Largest measured flow of each year at EEL R A VAN ARSDALE DAM NR POTTER VALLEY CA

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1910–2025.

Show relevant events (1 event)Shading marks when something was recorded, not what caused the line.

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 (1 event)

A shaded period marks when something was recorded, not what caused the shape of the line. Where the two coincide, they coincided.

Documented record — A documented event, compiled from cited sources after it happened. The dates are as good as the record, which for older events can mean the month rather than the day.

Event	Type	Period	Standing	Authority
Hurricane Katrina water and sanitation collapse	Flood	2005-08-29 – 2005-09-30	Documented record	Compiled record

Not shown on this chart

The 1976 drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
The 2022 drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
Yorkshire drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
Cantareira water crisis, São Paulo — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
Cape Town Day Zero — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
European drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.

View the data behind this chart

Underlying data
Period	EEL R A VAN ARSDALE DAM NR POTTER VALLEY CA (m³/s)
1910	261
1911	399
1912	281
1913	450
1915	892
1916	631
1917	1,124
1918	320
1919	510
1920	193
1922	79.6
1923	58.3
1924	37.7
1925	504
1926	228
1927	646
1928	1,133
1929	23.5
1930	162
1931	28.9
1933	96.8
1935	225
1936	490
1937	123
1939	90.6
1940	1,068
1941	614
1942	643
1943	895
1944	207
1945	197
1947	258
1948	200
1949	183
1950	210
1951	558
1952	739
1953	824
1954	379
1955	28.3
1957	357
1958	714
1959	263
1960	841
1961	255
1962	311
1963	790
1964	133
1966	580
1967	467
1968	283
1969	631
1970	1,025
1971	634
1972	123
1973	498
1974	1,121
1975	535
1976	55.2
1978	595
1979	126
1980	716
1981	132
1983	793
1984	178
1986	1,453
1987	275
1988	215
1989	280
1990	104
1991	43.6
1992	192
1993	782
1994	17.0
1995	816
1996	303
1997	954
1998	425
1999	374
2000	306
2001	53.0
2002	379
2004	742
2005	513
2007	111
2008	170
2009	161
2010	204
2012	251
2014	100.0
2016	462
2017	827
2018	311
2019	889
2020	26.6
2021	24.5
2023	699
2024	343
2025	1,172

About this series

Everything below is a property of the data rather than a rating of it. There is deliberately no single confidence score: how much a gap matters depends on what you are about to do with the series, and only you know that.

Source	United States Geological Survey — National Water Information System · US Government work — public domain
How the values came to exist	Measured
Period held	1910–2025
Completeness	85.3% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	17 separate periods inside 1910–2025 hold no value. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1910 and is not continuous from it: 116 years separate the first value from the last, and 85% of the years between them are held. The span is not the record.
Last read from the publisher	2026-08-31
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?

Water leaving the catchment above EEL R A VAN ARSDALE DAM NR POTTER VALLEY CA, as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1910–2024.

Show relevant events (1 event)Shading marks when something was recorded, not what caused the line.

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 (1 event)

A shaded period marks when something was recorded, not what caused the shape of the line. Where the two coincide, they coincided.

Documented record — A documented event, compiled from cited sources after it happened. The dates are as good as the record, which for older events can mean the month rather than the day.

Event	Type	Period	Standing	Authority
Hurricane Katrina water and sanitation collapse	Flood	2005-08-29 – 2005-09-30	Documented record	Compiled record

Not shown on this chart

The 1976 drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
The 2022 drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
Yorkshire drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
Cantareira water crisis, São Paulo — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
Cape Town Day Zero — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
European drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.

View the data behind this chart

Underlying data
Period	EEL R A VAN ARSDALE DAM NR POTTER VALLEY CA (mm)
1910	315
1911	484
1912	238
1913	451
1914	931
1915	897
1916	668
1917	405
1918	147
1919	450
1920	398
1921	486
1922	165
1923	105
1924	9.00
1925	386
1926	182
1928	352
1929	19.0
1930	236
1931	38.0
1932	124
1933	142
1934	135
1935	371
1936	526
1937	515
1938	960
1939	70.0
1940	920
1941	1,030
1942	664
1943	430
1944	135
1945	475
1946	179
1947	116
1948	319
1949	219
1950	494
1951	542
1952	675
1953	599
1954	472
1955	373
1956	666
1957	328
1958	1,029
1959	185
1960	362
1961	301
1962	312
1963	504
1964	505
1965	503
1966	443
1967	524
1968	313
1969	833
1970	848
1971	408
1972	192
1973	887
1974	784
1975	556
1976	15.0
1977	33.0
1978	760
1979	195
1980	674
1981	526
1982	1,112
1983	1,708
1984	274
1985	74.0
1986	929
1987	208
1988	194
1989	234
1990	60.0
1991	76.0
1992	148
1993	621
1994	57.0
1995	1,220
1996	912
1997	492
1998	1,370
1999	587
2000	371
2001	193
2002	396
2003	534
2004	456
2005	813
2006	896
2007	187
2008	305
2009	181
2010	666
2011	606
2012	524
2013	122
2014	230
2015	172
2016	778
2017	1,135
2018	189
2019	901
2020	112
2021	217
2022	237
2023	863
2024	1,042

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	1910–2024
Completeness	99.1% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	One period inside 1910–2024 holds no value: 1927. It is drawn as a break in the line and is never interpolated across.
Continuity	The record begins in 1910 and is not continuous from it: 115 years separate the first value from the last, and 99% of the years between them are held. The span is not the record.
Last read from the publisher	2026-08-24
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

Gauges within the Upper Eel and what each holds
Gauge	Measures	Values	Record
EEL R A VAN ARSDALE DAM NR POTTER VALLEY CA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	266	1910–2026
EEL R BL SCOTT DAM NR POTTER VALLEY CA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	241	1923–2026

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 — 18010103. 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.

What each gauge’s link to this water rests on
Gauge	Evidence	Established
EEL R A VAN ARSDALE DAM NR POTTER VALLEY 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	2026-08-26
EEL R BL SCOTT DAM NR POTTER VALLEY 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	2026-08-26

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 3 of them, which makes it a full profile.

Information-gain signals held for this water body
Signal	Held	Counts
Gauges holding a real record	2	no
Years spanned	117	yes, 20 or more
Values held	507	no
Distinct measurements	4	yes, 2 or more
Publishers measuring it	2	yes, 2 or more
Official identifiers	1	recorded, not counted

Use this data

Machine-readable JSON /api/v1/observations/by-subject/gauge-usgs-11471500.json
How to cite this, and who you must credit
How these figures were produced
Request this at a different scale, format or geography

No bulk download is offered here, which is a licence position rather than a product one: at least one contributing publisher does not permit redistribution. The values can be read on the page, cited, and pointed to at source.

Attribution and citation

Suggested citation for Hydrionis

Hydrionis (2026), Upper Eel gauge records, accessed 2026-09-02, hydrionis.com/waters/united-states-upper-eel/

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.

Recommended, not required. Hydrionis does not claim rights over unmodified public data it relayed, and doing arithmetic on somebody else’s measurements does not make them Hydrionis’s. Cite the version and the access date: the Upper Eel gauge records changes as publishers release and as methods are revised, and a citation without both cannot be checked later. Full guidance is on cite and reuse.

None of the contributing licences requires attribution. Crediting the publishers is still good practice and they are listed above.

Where these figures come from

MeasuredHigh confidence2025-02-04

Source: USGS — National Water Information System, USGS site 11471500, 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 31 August 2026.