The monitoring network within this area

Hydrionis holds 979 values from 3 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

979

Values held

1903–2026

Record spans

Gauges within the Saco River huc8 subbasin

3 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 Saco River at Cornish, Maine

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1917–2025.

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	Saco River at Cornish, Maine (m³/s)
1917	498
1918	221
1919	382
1920	399
1921	357
1922	510
1923	651
1924	365
1925	450
1926	357
1927	221
1928	385
1929	306
1930	270
1931	331
1932	391
1933	552
1934	402
1935	271
1936	1,320
1937	479
1938	337
1939	399
1940	609
1941	178
1942	289
1943	337
1944	343
1945	447
1946	268
1947	323
1948	279
1949	357
1950	484
1951	484
1952	479
1953	1,201
1954	646
1955	309
1956	328
1957	129
1958	572
1959	331
1960	476
1961	270
1962	402
1963	379
1965	168
1966	174
1968	391
1969	725
1970	439
1971	411
1972	419
1973	490
1975	260
1976	544
1977	365
1978	439
1979	510
1980	334
1981	496
1982	450
1983	456
1984	660
1985	150
1986	436
1987	886
1988	320
1989	518
1990	289
1991	264
1992	235
1993	515
1994	422
1995	183
1996	436
1997	419
1998	779
1999	278
2000	360
2001	447
2002	331
2003	258
2005	484
2006	422
2007	481
2008	501
2009	399
2010	498
2011	413
2012	425
2014	558
2015	300
2016	221
2017	413
2019	583
2020	357
2022	229
2023	586
2025	253

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	1917–2025
Completeness	92.7% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	8 separate periods inside 1917–2025 hold no value. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1917 and is not continuous from it: 109 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	2026-10-01
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?

Water leaving the catchment above Saco River at Cornish, Maine, as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1917–2025.

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	Saco River at Cornish, Maine (mm)
1917	819
1918	612
1919	729
1920	875
1921	617
1922	811
1923	652
1924	727
1925	732
1926	596
1927	709
1928	809
1929	626
1930	609
1931	562
1932	670
1933	627
1934	628
1935	695
1936	926
1937	956
1938	766
1939	587
1940	704
1941	396
1942	586
1943	759
1944	641
1945	920
1946	754
1947	690
1948	553
1949	564
1950	766
1951	931
1952	916
1953	935
1954	1,122
1955	647
1956	737
1957	510
1958	762
1959	698
1960	902
1961	587
1962	723
1963	653
1964	521
1965	380
1966	565
1967	557
1968	659
1969	998
1970	782
1971	625
1972	780
1973	1,207
1974	817
1975	698
1976	886
1977	802
1978	733
1979	879
1980	464
1981	740
1982	674
1983	950
1984	866
1985	483
1986	768
1987	671
1988	563
1989	726
1990	856
1991	707
1992	596
1993	626
1994	649
1995	616
1996	1,085
1997	728
1998	966
1999	782
2000	691
2001	496
2002	526
2003	822
2004	626
2005	1,144
2006	1,024
2007	714
2008	1,093
2009	984
2010	889
2011	1,010
2012	781
2013	734
2014	787
2015	577
2016	575
2017	896
2018	778
2019	914
2020	752
2021	593
2022	771
2023	1,204
2024	793
2025	598

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	1917–2025
Completeness	100.0% of the periods in that span are held.
Continuity	Continuous: every year from 1917 to 2025 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

Gauges within the Saco River and what each holds
Gauge	Measures	Values	Record
Saco River at Cornish, Maine	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	364	1916–2026
Saco River near Conway, NH	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	339	1903–2026
OSSIPEE RIVER AT CORNISH, ME	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	276	1916–2026

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 — 01060002. 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
Saco River at Cornish, Maine	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
Saco River near Conway, 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	2026-10-02
OSSIPEE RIVER AT CORNISH, ME	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.

Information-gain signals held for this water body
Signal	Held	Counts
Gauges holding a real record	3	yes, 3 or more
Years spanned	124	yes, 20 or more
Values held	979	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

Machine-readable JSON /api/v1/observations/by-subject/gauge-usgs-01066000.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), Saco River gauge records, accessed 2026-10-05, hydrionis.com/waters/united-states-saco-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 Saco 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 confidence2025-03-21

Source: USGS — National Water Information System, USGS site 01066000, 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.