The monitoring network within this area

Hydrionis holds 495 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

495

Values held

1905–2026

Record spans

Gauges within the Upper Androscoggin River 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 Androscoggin River at Errol, NH

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1906–2025.

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	Androscoggin River at Errol, NH (m³/s)
1906	185
1907	217
1909	276
1910	200
1911	128
1912	176
1913	196
1914	207
1916	185
1917	365
1919	210
1920	150
1921	123
1922	200
1923	283
1924	150
1925	275
1927	158
1928	379
1929	447
1930	218
1931	111
1932	227
1933	385
1934	264
1935	239
1936	362
1937	281
1938	281
1939	235
1940	292
1941	197
1942	371
1943	459
1944	238
1945	276
1946	176
1947	323
1948	132
1949	130
1950	138
1951	176
1952	249
1953	185
1954	309
1955	273
1956	155
1957	56.9
1958	213
1959	211
1960	261
1961	149
1962	195
1963	150
1964	85.2
1966	116
1967	134
1968	168
1969	467
1970	211
1971	135
1972	173
1973	297
1974	331
1975	122
1976	197
1977	152
1978	206
1979	175
1980	76.7
1981	209
1982	184
1983	197
1984	377
1985	114
1986	150
1987	249
1988	146
1989	270
1990	154
1991	292
1993	188
1994	249
1995	123
1996	268
1997	146
1998	368
1999	155
2000	436
2001	255
2002	306
2003	138
2005	241
2007	357
2008	249
2009	244
2010	182
2011	340
2012	224
2013	282
2014	251
2015	204
2016	133
2017	331
2018	234
2019	323
2020	172
2021	102
2022	180
2023	190
2025	198

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	1906–2025
Completeness	92.5% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	9 separate periods inside 1906–2025 hold no value. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1906 and is not continuous from it: 120 years separate the first value from the last, and 93% 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 Androscoggin River at Errol, NH, as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1905–2025.

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	Androscoggin River at Errol, NH (mm)
1905	528
1906	569
1907	662
1908	655
1909	611
1910	525
1911	341
1913	749
1914	553
1915	424
1916	632
1917	798
1918	594
1919	659
1920	607
1921	510
1922	564
1923	533
1924	521
1925	664
1926	666
1927	607
1928	849
1929	809
1930	542
1931	457
1932	643
1933	726
1934	644
1935	647
1936	805
1937	759
1938	641
1939	582
1940	469
1941	399
1942	522
1943	675
1944	595
1945	782
1946	597
1947	789
1948	494
1949	484
1950	601
1951	699
1952	639
1953	580
1954	922
1955	737
1956	557
1957	482
1958	756
1959	659
1960	756
1961	567
1962	568
1963	688
1964	584
1965	426
1966	537
1967	534
1968	559
1969	761
1970	777
1971	583
1972	628
1973	820
1974	866
1975	555
1976	787
1977	726
1978	783
1979	587
1980	460
1981	614
1982	692
1983	631
1984	751
1985	505
1986	628
1987	543
1988	519
1989	672
1990	758
1991	783
1992	571
1993	597
1994	639
1995	537
1996	983
1997	680
1998	702
1999	602
2000	754
2001	507
2002	571
2003	646
2004	668
2005	949
2006	834
2007	880
2008	992
2009	807
2010	747
2011	958
2012	667
2013	732
2014	712
2015	652
2016	554
2017	824
2018	703
2019	833
2020	685
2021	429
2022	614
2023	834
2024	716
2025	626

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	1905–2025
Completeness	99.2% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	One period inside 1905–2025 holds no value: 1912. It is drawn as a break in the line and is never interpolated across.
Continuity	The record begins in 1905 and is not continuous from it: 121 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 Androscoggin River and what each holds
Gauge	Measures	Values	Record
Androscoggin River near Gorham, NH	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	254	1913–2026
Androscoggin River at Errol, NH	catchment area, annual maximum river flow, mean river flow	241	1905–2026

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 — 01040001. 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
Androscoggin River near Gorham, NH	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
Androscoggin River at Errol, NH	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	122	yes, 20 or more
Values held	495	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-01054000.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 Androscoggin River gauge records, accessed 2026-09-02, hydrionis.com/waters/united-states-upper-androscoggin-river/

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 Androscoggin River 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 confidence2025-03-17

Source: USGS — National Water Information System, USGS site 01054000, 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.