la Loire — monitoring and records

The monitoring network on this water

Hydrionis holds 14,683 values from 16 gauges on this water. Discharge is a property of a gauge and its reach, not of this water as a whole, so this page reports the network and its records rather than a single figure.

Gauges

14,683

Values held

1900–2026

Record spans

111,570 km²

Catchment above the deepest gauge

The seasonal shape

An annual mean says how much water a river carried. A monthly record says when — and on most rivers the difference between a wet winter and a dry summer is larger than the difference between one year and the next.

Monthly mean flow at La Loire à Chalonnes-sur-Loire et à Ingrandes et à Montjean-sur-Loire et à Saint-Florent-le-Vieil

Each month's mean discharge as the publisher computed it, which shows the seasonal shape an annual mean flattens away. 1900–2026.

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

Taken as the publisher computes it rather than recomputed by Hydrionis from daily values: the publisher knows which of its readings passed validation. Months the gauge did not cover are absent rather than interpolated, and the line breaks where they fall.

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
European drought	Drought declaration	2022-05-01 – 2022-10-31	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.
Hurricane Katrina water and sanitation collapse — 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	La Loire à Chalonnes-sur-Loire et à Ingrandes et à Montjean-sur-Loire et à Saint-Florent-le-Vieil (m³/s)
1900	891
1901	775
1902	1,180
1903	940
1904	921
1905	336
1906	1,850
1907	1,059
1908	785
1909	1,178
1910	2,685
1911	1,648
1912	2,431
1913	1,434
1914	945
1915	2,172
1916	1,431
1917	1,999
1918	1,592
1919	2,837
1920	2,044
1921	523
1922	509
1923	2,024
1924	2,947
1925	777
1926	2,538
1927	1,088
1928	1,961
1929	1,131
1930	2,248
1931	2,372
1932	1,258
1933	719
1934	1,210
1935	1,341
1936	3,855
1937	850
1938	1,378
1939	2,653
1940	1,392
1941	2,361
1942	921
1943	1,695
1944	616
1945	1,176
1946	555
1947	792
1948	1,211
1949	524
1950	574
1951	1,464
1952	1,929
1953	1,788
1954	503
1955	2,630
1956	671
1957	708
1958	1,298
1959	2,744
1960	1,494
1961	3,008
1962	2,014
1963	994
1964	411
1965	962
1966	3,186
1967	1,824
1968	2,957
1969	1,887
1970	1,338
1971	763
1972	753
1973	674
1974	1,172
1975	1,197
1976	716
1977	1,245
1978	1,722
1979	1,081
1980	2,090
1981	2,693
1982	3,415
1983	1,526
1984	1,537
1985	1,220
1986	973
1987	1,402
1988	2,469
1989	494
1990	333
1991	1,395
1992	344
1993	1,053
1994	3,605
1995	2,701
1996	2,000
1997	1,086
1998	1,891
1999	1,483
2000	2,112
2001	2,134
2002	838
2003	2,306
2004	2,768
2005	1,067
2006	614
2007	1,088
2008	1,434
2009	1,218
2010	1,216
2011	1,245
2012	1,484
2013	1,808
2014	1,890
2015	1,227
2016	933
2017	408
2018	2,375
2019	476
2020	1,236
2021	1,559
2022	1,469
2023	965
2024	1,477
2025	2,270
2026	959

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	Office français de la biodiversité / SCHAPI — Hydrométrie — French river flow and stage · Licence Ouverte / Open Licence v2.0 (Etalab)
How the values came to exist	Measured
Period held	1900–2026
Completeness	100.0% of the periods in that span are held.
Continuity	Continuous: every year from 1900 to 2026 is held.
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

Every gauge Hydrionis holds here

Gauges on the la Loire and what each holds
Gauge	Measures	Values	Record
La Loire à Chalonnes-sur-Loire et à Ingrandes et à Montjean-sur-Loire et à Saint-Florent-le-Vieil	mean monthly river flow	1,521	1900–2026
La Loire à Blois	mean monthly river flow	1,465	1900–2026
La Loire à Montsoreau et à Saumur	mean monthly river flow	1,329	1916–2026
La Loire à Bas-en-Basset	mean monthly river flow	1,293	1919–2026
La Loire à Villerest	mean monthly river flow	1,267	1921–2026
La Loire à Chadrac	mean monthly river flow	1,245	1921–2026
La Loire à Saint-Martin-sur-Ocre et à Gien	mean monthly river flow	1,049	1936–2026
La Loire à Usclades-et-Rieutord	mean monthly river flow	860	1955–2026
La Loire à Nevers	mean monthly river flow	860	1955–2026
La Loire à Digoin	mean monthly river flow	819	1958–2026
La Loire à Orléans	mean monthly river flow	725	1964–2026
La Loire à Cours-les-Barres	mean monthly river flow	688	1967–2026
La Loire [totale] à Nantes [Malakoff]	mean monthly river flow	401	1993–2026
La Loire à Langeais	mean monthly river flow	400	1985–2026
La Loire à Onzain	mean monthly river flow	392	1994–2026
La Loire à Tours	mean monthly river flow	369	1996–2026

How these gauges were attached to this water

Named by the publisher Each gauge here names this water in the publisher’s own station record. Hydrionis has not inferred the connection from station names.

What each gauge’s link to this water rests on
Gauge	Evidence	Established
La Loire à Chalonnes-sur-Loire et à Ingrandes et à Montjean-sur-Loire et à Saint-Florent-le-Vieil	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Blois	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Montsoreau et à Saumur	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Bas-en-Basset	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Villerest	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Chadrac	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Saint-Martin-sur-Ocre et à Gien	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Usclades-et-Rieutord	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Nevers	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Digoin	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Orléans	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Cours-les-Barres	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire [totale] à Nantes [Malakoff]	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Langeais	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Onzain	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	2026-10-02
La Loire à Tours	Stated by the publisher — Hub'Eau hydrometry site reference, libelle_cours_eau, code_cours_eau and surface_bv fields — https://hubeau.eaufrance.fr/api/v2/hydrometrie/referentiel/sites	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 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	16	yes, 3 or more
Years spanned	127	yes, 20 or more
Values held	14,683	yes, 1000 or more
Distinct measurements	1	no
Publishers measuring it	1	no
Official identifiers	2	recorded, not counted

Use this data

Machine-readable JSON /api/v1/observations/by-subject/gauge-fr-m5300010.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

Attribution you are required to give

These are conditions of the licences the underlying data is published under. They are obligations to the publishers, not to Hydrionis, and they apply to you directly whether or not you mention Hydrionis at all.

Source: Hub’Eau / Système d’information sur l’eau, under Licence Ouverte (Etalab).

Office français de la biodiversité / SCHAPI — Licence Ouverte / Open Licence v2.0 (Etalab) (licence text)

Suggested citation for Hydrionis

Hydrionis (2026), la Loire gauge records, accessed 2026-10-05, hydrionis.com/waters/france-la-loire/

Cite Hydrionis where you rely on the compilation, the normalisation, the eligibility judgements or a chart. Where you use an unmodified published value, the publisher’s attribution is the one that is required; crediting Hydrionis as well is welcome and is not something Hydrionis can require of you.

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 la Loire 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.

Where these figures come from

MeasuredHigh confidenceSeptember 2026

Source: Hub'Eau — Hydrométrie — French river flow and stage, M5300010. Licence: Open — attribution required (attribution required).

Method: Monthly mean discharge (QmM) computed by the publisher from its validated sub-hourly record, reported in litres per second and converted to cubic metres per second as they are collected. Where a site has been measured by more than one station, the station with the longest published series is used rather than blending stations whose values for the same month can differ.

Measured on la Loire.

Retrieved 1 October 2026.