The monitoring network within this area

Hydrionis holds 414 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

414

Values held

1867–2026

Record spans

Gauges within the Middle Tennessee-Chickamauga 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 TENNESSEE RIVER AT CHATTANOOGA, TN

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1867–2008.

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	TENNESSEE RIVER AT CHATTANOOGA, TN (m³/s)
1867	12,997
1874	5,522
1875	11,610
1877	5,380
1878	3,540
1879	7,136
1880	7,192
1882	7,787
1883	7,391
1884	8,070
1885	4,927
1886	11,072
1887	5,125
1888	5,040
1889	5,607
1890	8,014
1891	7,334
1892	7,136
1893	6,258
1894	4,729
1895	6,003
1896	7,617
1897	7,277
1898	4,729
1899	7,730
1900	4,502
1901	6,258
1902	7,674
1903	5,947
1904	4,078
1905	4,134
1906	3,964
1908	4,616
1909	4,616
1910	2,452
1911	5,607
1912	5,380
1913	6,286
1914	2,973
1915	5,578
1917	9,656
1918	7,646
1919	5,352
1920	7,787
1921	6,031
1922	6,485
1923	5,324
1924	4,049
1926	2,631
1928	5,210
1929	7,023
1931	3,540
1932	5,437
1933	6,824
1934	6,088
1935	4,955
1936	6,626
1937	5,777
1938	3,851
1939	5,465
1940	2,532
1941	1,648
1942	2,047
1944	5,692
1945	3,256
1946	6,371
1947	5,267
1948	6,371
1949	5,069
1950	5,437
1951	3,964
1953	3,030
1954	5,239
1955	3,341
1956	5,295
1957	5,890
1959	3,115
1961	5,040
1963	6,201
1964	3,455
1965	5,097
1966	2,945
1967	3,398
1969	3,426
1971	2,568
1972	3,285
1973	7,561
1974	5,125
1975	4,191
1976	1,903
1977	5,409
1978	3,256
1979	4,106
1980	4,757
1981	1,438
1982	3,766
1983	3,285
1984	6,768
1985	2,294
1986	1,875
1987	3,087
1988	2,098
1989	4,899
1990	4,786
1991	4,134
1993	3,200
1994	5,720
1995	2,829
1996	4,106
1997	3,908
1998	5,862
1999	2,588
2000	3,879
2001	2,438
2002	5,210
2003	6,824
2004	4,531
2006	1,807
2007	1,877
2008	1,580

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	1867–2008
Completeness	84.5% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	17 separate periods inside 1867–2008 hold no value. The longest runs from 1868 to 1873 — 6 years with no reading. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1867 and is not continuous from it: 142 years separate the first value from the last, and 85% 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 SOUTH CHICKAMAUGA CREEK NEAR CHICKAMAUGA, TN, as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1929–2025.

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	SOUTH CHICKAMAUGA CREEK NEAR CHICKAMAUGA, TN (mm)
1929	947
1930	408
1931	380
1932	834
1933	441
1934	442
1935	555
1936	702
1937	520
1938	545
1939	529
1940	328
1941	298
1942	443
1943	440
1944	587
1945	536
1946	801
1947	555
1948	770
1949	754
1950	771
1951	665
1952	477
1953	485
1954	440
1955	477
1956	490
1957	726
1958	434
1959	387
1960	456
1961	729
1962	670
1963	576
1964	812
1965	446
1966	469
1967	629
1968	378
1969	487
1970	378
1971	511
1972	654
1973	901
1974	564
1975	775
1976	520
1977	762
1981	319
1982	682
1983	677
1984	602
1985	363
1986	339
1987	422
1988	239
1989	889
1990	884
1991	663
1992	588
1993	499
2013	934
2014	456
2015	609
2016	381
2017	515
2018	867
2019	894
2020	967
2021	732
2022	634
2023	478
2024	423
2025	477

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	1929–2025
Completeness	77.3% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	2 separate periods inside 1929–2025 hold no value. The longest runs from 1994 to 2012 — 19 years with no reading. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1929 and is not continuous from it: 97 years separate the first value from the last, and 77% 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 Middle Tennessee-Chickamauga and what each holds
Gauge	Measures	Values	Record
TENNESSEE RIVER AT CHATTANOOGA, TN	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	226	1867–2026
SOUTH CHICKAMAUGA CREEK NEAR CHICKAMAUGA, TN	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	188	1929–2026

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 — 06020001. 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
TENNESSEE RIVER AT CHATTANOOGA, TN	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
SOUTH CHICKAMAUGA CREEK NEAR CHICKAMAUGA, TN	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	160	yes, 20 or more
Values held	414	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-03568000.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), Middle Tennessee-Chickamauga gauge records, accessed 2026-09-02, hydrionis.com/waters/united-states-middle-tennessee-chickamauga/

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 Middle Tennessee-Chickamauga 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 confidence2008-02-07

Source: USGS — National Water Information System, USGS site 03568000, 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.