The monitoring network within this area

Hydrionis holds 399 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

399

Values held

1918–2026

Record spans

Gauges within the South Skunk 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 South Skunk River near Ames, IA

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1921–2025.

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	South Skunk River near Ames, IA (m³/s)
1921	100
1922	95.4
1923	47.3
1924	85.2
1925	25.6
1926	88.3
1927	69.7
1929	148
1933	56.4
1934	17.0
1935	98.8
1936	73.1
1937	85.0
1938	81.8
1939	91.5
1940	65.7
1941	86.4
1942	71.6
1943	127
1944	228
1945	114
1946	64.3
1947	185
1948	74.2
1949	85.0
1950	108
1951	151
1952	46.2
1953	27.8
1954	244
1956	10.6
1957	100
1958	89.2
1959	48.7
1960	176
1961	56.4
1962	122
1963	51.5
1964	61.4
1965	149
1966	82.1
1967	79.0
1968	138
1969	124
1970	37.7
1971	104
1972	85.8
1973	94.6
1974	164
1975	148
1976	101
1977	150
1978	63.4
1979	141
1980	77.0
1981	53.2
1982	98.8
1983	146
1984	142
1985	56.1
1986	114
1987	86.1
1989	10.5
1990	187
1991	133
1992	66.5
1993	317
1994	66.3
1995	46.4
1996	396
1997	58.9
1998	135
1999	103
2000	25.7
2001	56.4
2002	30.3
2003	57.5
2004	71.4
2005	65.4
2006	94.3
2007	184
2008	311
2009	129
2010	419
2011	45.9
2012	20.7
2013	191
2014	262
2015	317
2017	53.5
2018	124
2019	191
2020	92.3
2021	12.9
2022	119
2023	82.4
2024	78.4
2025	90.3

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	1921–2025
Completeness	93.3% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	5 separate periods inside 1921–2025 hold no value. The longest runs from 1930 to 1932 — 3 years with no reading. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1921 and is not continuous from it: 105 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	2026-08-31
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 Skunk River near Ames, IA, as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1921–2025.

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 Skunk River near Ames, IA (mm)
1921	153
1922	118
1923	103
1924	211
1925	37.0
1926	125
1933	66.0
1934	22.0
1935	189
1936	103
1937	79.0
1938	128
1939	71.0
1940	59.0
1941	152
1942	239
1943	207
1944	309
1945	244
1946	135
1947	283
1948	100
1949	90.0
1950	124
1951	309
1952	137
1953	80.0
1954	205
1955	57.0
1956	8.00
1957	98.0
1958	128
1959	146
1960	245
1961	222
1962	298
1963	96.0
1964	55.0
1965	313
1966	126
1967	92.0
1968	76.0
1969	374
1970	108
1971	140
1972	308
1973	482
1974	372
1975	279
1976	143
1977	144
1978	190
1979	336
1980	113
1981	32.0
1982	348
1983	521
1984	381
1985	137
1986	389
1987	244
1988	56.0
1989	21.0
1990	336
2002	123
2003	134
2004	205
2005	135
2006	204
2007	477
2008	548
2009	437
2010	673
2011	174
2012	43.0
2013	238
2014	285
2015	456
2016	330
2017	253
2018	530
2019	445
2020	228
2021	61.0
2022	167
2023	112
2024	203
2025	335

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	1921–2025
Completeness	83.8% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	2 separate periods inside 1921–2025 hold no value. The longest runs from 1991 to 2001 — 11 years with no reading. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1921 and is not continuous from it: 105 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	2026-08-24
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 South Skunk and what each holds
Gauge	Measures	Values	Record
South Skunk River near Ames, IA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	226	1921–2026
Ioway Creek at Ames, IA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	173	1918–2026

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 — 07080105. 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
South Skunk River near Ames, IA	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
Ioway Creek at Ames, IA	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	109	yes, 20 or more
Values held	399	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-05470000.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), South Skunk gauge records, accessed 2026-09-02, hydrionis.com/waters/united-states-south-skunk/

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 South Skunk 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 confidence2025-08-10

Source: USGS — National Water Information System, USGS site 05470000, 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.