The monitoring network within this area

Hydrionis holds 402 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

402

Values held

1903–2026

Record spans

Gauges within the Lower Yellowstone 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 Yellowstone River near Sidney MT

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1911–2024.

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	Yellowstone River near Sidney MT (m³/s)
1911	2,220
1912	3,228
1913	2,090
1914	2,265
1915	2,758
1916	2,860
1918	3,568
1919	748
1920	2,540
1921	4,502
1922	2,447
1923	1,824
1925	1,999
1926	1,501
1927	2,860
1928	2,517
1929	2,679
1930	1,155
1931	1,305
1934	498
1935	2,203
1936	1,784
1937	1,849
1938	2,384
1939	1,600
1940	1,065
1941	1,218
1942	1,931
1943	3,738
1944	3,398
1945	1,883
1946	1,416
1948	2,203
1949	1,359
1950	1,909
1951	1,413
1952	3,908
1953	1,846
1954	1,172
1955	1,104
1956	1,829
1957	1,982
1958	1,099
1959	1,623
1960	1,642
1961	869
1962	1,948
1963	2,435
1964	2,044
1965	2,832
1966	793
1967	2,339
1968	2,019
1969	1,727
1970	1,781
1971	1,781
1972	1,682
1973	1,351
1974	2,163
1975	2,180
1976	1,413
1977	796
1978	3,143
1980	1,000
1981	1,608
1982	1,781
1983	1,186
1984	1,252
1985	841
1986	1,696
1987	651
1988	934
1989	1,065
1990	1,152
1991	1,775
1992	1,147
1993	1,447
1994	2,124
1995	1,631
1996	1,849
1997	2,415
1998	1,254
1999	1,538
2000	1,019
2001	705
2002	1,235
2003	1,390
2004	731
2005	1,362
2006	954
2007	1,186
2008	1,606
2009	1,467
2010	1,603
2011	3,511
2012	1,141
2013	1,538
2014	1,977
2015	1,713
2016	900
2017	1,628
2018	2,285
2019	1,671
2020	1,518
2021	1,053
2022	2,090
2023	1,685
2024	1,464

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	1911–2024
Completeness	94.7% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	5 separate periods inside 1911–2024 hold no value. The longest runs from 1932 to 1933 — 2 years with no reading. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1911 and is not continuous from it: 114 years separate the first value from the last, and 95% 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 Yellowstone River near Sidney MT, as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1911–2024.

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	Yellowstone River near Sidney MT (mm)
1911	67.0
1912	97.0
1913	81.0
1914	69.0
1915	73.0
1916	82.0
1917	97.0
1918	93.0
1919	36.0
1920	77.0
1921	61.0
1922	61.0
1923	81.0
1924	96.0
1925	91.0
1926	65.0
1927	96.0
1928	84.0
1929	72.0
1930	60.0
1934	28.0
1935	48.0
1936	46.0
1937	48.0
1938	63.0
1939	45.0
1940	38.0
1941	56.0
1942	64.0
1943	93.0
1944	80.0
1945	66.0
1946	57.0
1947	77.0
1948	69.0
1949	53.0
1950	68.0
1951	66.0
1952	64.0
1953	48.0
1954	47.0
1955	44.0
1956	62.0
1957	70.0
1958	50.0
1959	54.0
1960	35.0
1961	33.0
1962	74.0
1963	65.0
1964	68.0
1965	90.0
1966	38.0
1967	81.0
1968	77.0
1969	65.0
1970	72.0
1971	90.0
1972	80.0
1973	65.0
1974	76.0
1975	91.0
1976	74.0
1977	35.0
1978	93.0
1979	58.0
1980	55.0
1981	53.0
1982	73.0
1983	65.0
1984	65.0
1985	40.0
1986	70.0
1987	41.0
1988	35.0
1989	46.0
1990	47.0
1991	66.0
1992	49.0
1993	68.0
1994	44.0
1995	69.0
1996	75.0
1997	100
1998	60.0
1999	67.0
2000	41.0
2001	30.0
2002	36.0
2003	38.0
2004	30.0
2005	44.0
2006	40.0
2007	40.0
2008	62.0
2009	64.0
2010	59.0
2011	114
2012	44.0
2013	43.0
2014	83.0
2015	54.0
2016	42.0
2017	83.0
2018	98.0
2019	80.0
2020	56.0
2021	36.0
2022	53.0
2023	74.0
2024	50.0

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	1911–2024
Completeness	97.4% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	One period inside 1911–2024 holds no value: 1931 to 1933, 3 years with no reading. It is drawn as a break in the line and is never interpolated across.
Continuity	The record begins in 1911 and is not continuous from it: 114 years separate the first value from the last, and 97% of the years between them are held. The span is not the record.
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 Lower Yellowstone and what each holds
Gauge	Measures	Values	Record
Yellowstone River near Sidney MT	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	369	1910–2026
Yellowstone River at Glendive, MT	catchment area, annual maximum river flow	33	1903–2026

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 — 10100004. 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
Yellowstone River near Sidney MT	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
Yellowstone River at Glendive, MT	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 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	1	no
Years spanned	124	yes, 20 or more
Values held	402	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-06329500.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), Lower Yellowstone gauge records, accessed 2026-10-05, hydrionis.com/waters/united-states-lower-yellowstone/

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 Lower Yellowstone 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 confidence2024-06-14

Source: USGS — National Water Information System, USGS site 06329500, 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.