The monitoring network within this area

Hydrionis holds 461 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

461

Values held

1915–2026

Record spans

Gauges within the Eleven Point 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 Eleven Point River near Bardley, MO

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1915–2025.

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	Eleven Point River near Bardley, MO (m³/s)
1915	1,246
1922	214
1923	268
1924	47.6
1925	125
1927	1,133
1928	770
1929	227
1930	164
1931	74.8
1932	36.2
1933	286
1934	33.7
1935	572
1937	592
1938	258
1939	592
1940	185
1941	27.6
1942	801
1943	731
1944	194
1945	770
1946	323
1948	246
1949	940
1950	459
1951	199
1953	71.6
1954	306
1955	340
1956	153
1957	810
1958	294
1959	153
1961	459
1962	190
1963	173
1964	459
1965	49.6
1966	784
1967	39.4
1968	294
1969	572
1970	195
1971	69.9
1973	462
1974	371
1975	188
1976	209
1977	467
1978	173
1979	331
1981	36.5
1982	345
1983	221
1984	722
1985	360
1987	40.8
1988	248
1989	206
1990	180
1991	564
1992	513
1993	484
1994	467
1996	206
1997	223
1998	178
1999	87.5
2000	43.6
2001	37.9
2002	784
2003	39.6
2004	521
2005	154
2006	405
2008	1,399
2009	68.8
2011	946
2012	56.6
2013	255
2014	209
2015	185
2017	3,455
2018	294
2019	238
2020	388
2021	224
2022	274
2023	411
2024	297
2025	1,331

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	1915–2025
Completeness	83.8% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	13 separate periods inside 1915–2025 hold no value. The longest runs from 1916 to 1921 — 6 years with no reading. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1915 and is not continuous from it: 111 years separate the first value from the last, and 84% 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 Eleven Point River near Bardley, MO, as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1922–2025.

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	Eleven Point River near Bardley, MO (mm)
1922	328
1923	398
1924	195
1925	214
1926	240
1927	812
1928	569
1929	463
1930	310
1931	222
1932	174
1933	336
1934	125
1935	408
1936	131
1937	296
1938	308
1939	351
1940	184
1941	193
1942	419
1943	302
1944	190
1945	653
1946	483
1947	241
1948	272
1949	526
1950	563
1951	498
1952	398
1953	224
1954	154
1955	176
1956	135
1957	406
1958	434
1959	254
1960	258
1961	315
1962	278
1963	192
1964	239
1965	198
1966	351
1967	178
1968	371
1969	402
1970	275
1971	243
1972	283
1973	720
1974	530
1975	483
1976	253
1977	247
1978	286
1979	502
1980	206
1981	133
1982	411
1983	378
1984	513
1985	623
1986	333
1987	194
1988	312
1989	357
1990	393
1991	469
1992	315
1993	508
1994	545
1995	368
1996	372
1997	373
1998	298
1999	242
2000	150
2001	138
2002	453
2003	242
2004	314
2005	263
2006	307
2007	334
2008	578
2009	388
2010	333
2011	509
2012	250
2013	357
2014	321
2015	535
2016	459
2017	586
2018	297
2019	559
2020	657
2021	472
2022	462
2023	371
2024	322
2025	558

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	1922–2025
Completeness	100.0% of the periods in that span are held.
Continuity	Continuous: every year from 1922 to 2025 is held.
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 Eleven Point and what each holds
Gauge	Measures	Values	Record
Eleven Point River near Bardley, MO	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	246	1915–2026
Eleven Point River near Ravenden Springs, AR	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	215	1930–2026

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 — 11010011. 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
Eleven Point River near Bardley, MO	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
Eleven Point River near Ravenden Springs, AR	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	112	yes, 20 or more
Values held	461	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-07071500.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), Eleven Point gauge records, accessed 2026-09-02, hydrionis.com/waters/united-states-eleven-point/

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 Eleven Point 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 confidence2025-04-05

Source: USGS — National Water Information System, USGS site 07071500, 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.