The monitoring network within this area

Hydrionis holds 3,649 values from 6 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.

6

Gauges

3,649

Values held

1906–2026

Record spans

Gauges within the Roaring Fork huc8 subbasin

6 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 ROARING FORK RIVER AT GLENWOOD SPRINGS, CO.

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1906–2025.

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	ROARING FORK RIVER AT GLENWOOD SPRINGS, CO. (m³/s)
1906	348
1907	254
1908	191
1909	328
1912	362
1914	402
1915	185
1916	241
1917	328
1918	498
1919	215
1920	348
1921	498
1922	255
1923	271
1924	354
1925	251
1926	273
1927	252
1928	311
1929	297
1930	250
1931	148
1932	242
1933	345
1934	116
1935	354
1936	244
1937	193
1938	379
1939	165
1940	151
1941	235
1942	246
1943	259
1944	208
1945	213
1946	271
1947	314
1948	294
1949	294
1950	201
1951	235
1952	368
1953	326
1954	98.5
1955	155
1956	253
1957	538
1958	394
1959	223
1960	193
1961	160
1962	223
1963	104
1964	168
1965	268
1966	110
1967	171
1968	217
1969	175
1970	190
1971	216
1972	187
1973	234
1974	155
1975	192
1976	132
1977	70.5
1978	233
1979	267
1980	228
1981	142
1983	343
1984	294
1985	297
1986	217
1987	171
1988	133
1989	94.6
1990	139
1991	144
1992	88.6
1993	209
1994	129
1995	368
1996	188
1997	231
1998	157
1999	177
2000	177
2001	110
2002	70.2
2003	217
2004	116
2005	180
2006	180
2007	127
2008	222
2009	189
2010	286
2011	261
2012	59.7
2013	143
2014	198
2015	226
2016	197
2017	180
2018	82.4
2019	254
2020	145
2021	106
2022	148
2023	160
2024	216
2025	95.1

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	1906–2025
Completeness	96.7% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	3 separate periods inside 1906–2025 hold no value. The longest runs from 1910 to 1911 — 2 years with no reading. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1906 and is not continuous from it: 120 years separate the first value from the last, and 97% 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 ROARING FORK RIVER AT GLENWOOD SPRINGS, CO., as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1972–2024.

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	ROARING FORK RIVER AT GLENWOOD SPRINGS, CO. (mm)
1972	263
1973	327
1974	265
1975	292
1976	226
1977	106
1978	285
1979	360
1980	318
1981	179
1982	313
1983	392
1984	510
1985	415
1986	404
1987	282
1988	201
1989	197
1990	175
1991	245
1992	194
1993	369
1994	221
1995	485
1996	338
1997	411
1998	313
1999	287
2000	223
2001	202
2002	125
2003	209
2004	186
2005	289
2006	282
2007	251
2008	361
2009	320
2010	258
2011	379
2012	143
2013	181
2014	303
2015	285
2016	255
2017	272
2018	157
2019	360
2020	185
2021	156
2022	221
2023	298
2024	259

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	Derived Computed by Hydrionis
Period held	1972–2024
Completeness	100.0% of the periods in that span are held.
Continuity	Continuous: every year from 1972 to 2024 is held.
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

The snow standing above this water

7 automated snow stations sit inside this drainage area, weighing the snowpack rather than measuring how deep it is.

657

Fullest snowpack recorded at Independence Pass, in 1995 (mm of water)

184

Thinnest, in 2026 (mm of water)

April

Month the pack is usually at its fullest

June

Month the pack has gone by, in half of years

Peak snowpack at Independence Pass

Water years 1981–2026. Each point is the fullest month of that snow season.

A water year runs October to September and is named for the year it ends, so the snow of one winter stays in one point. The value is the fullest month, not the fullest day: a pack that peaked sharply mid-month reads lower here than a single measurement taken at the right moment would.

View the data behind this chart

Underlying data
Period	Independence Pass (mm)
1981	251
1982	496
1983	456
1984	582
1985	417
1986	468
1987	406
1988	312
1989	362
1990	329
1991	411
1992	335
1993	577
1994	415
1995	657
1996	535
1997	544
1998	418
1999	399
2000	326
2001	343
2002	301
2003	409
2004	337
2005	368
2006	391
2007	385
2008	640
2009	517
2010	370
2011	551
2012	257
2013	346
2014	513
2015	363
2016	403
2017	423
2018	308
2019	516
2020	449
2021	317
2022	338
2023	434
2024	420
2025	359
2026	184

Read against the river

Independence Pass and ROARING FORK RIVER AT GLENWOOD SPRINGS, CO. both sit in this drainage area, and their records overlap by 44 years. That is the span the two have in common, not a count of years both actually hold — either record may have gaps inside it. The two are shown separately rather than on one axis: millimetres of stored water and cubic metres per second are not commensurable, and a difference between them would mean nothing.

Being in the same drainage area does not put the snowpack upstream of the gauge. A subbasin is an area, and snow on one tributary can join the river below a gauge on another — so a weak relationship here may say more about which tributary was measured than about the snow.

Every gauge Hydrionis holds within this area

Gauges within the Roaring Fork and what each holds
Gauge	Measures	Values	Record
ROARING FORK RIVER AT GLENWOOD SPRINGS, CO.	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	260	1906–2026
ROARING FORK RIVER AT ASPEN, CO.	catchment area, annual maximum river flow	44	1911–2026
FRYINGPAN RIVER AT NORRIE, CO.	catchment area, annual maximum river flow	43	1911–2026
NORTH FORK FRYINGPAN RIVER NEAR NORRIE, CO.	catchment area, annual maximum river flow	41	1911–2026
FRYINGPAN RIVER AT MEREDITH, CO.	catchment area, annual maximum river flow	19	1911–2026
MAROON CREEK NEAR ASPEN, CO.	catchment area, annual maximum river flow	9	2018–2026

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 — 14010004. 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
ROARING FORK RIVER AT GLENWOOD SPRINGS, CO.	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
ROARING FORK RIVER AT ASPEN, CO.	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
FRYINGPAN RIVER AT NORRIE, CO.	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
NORTH FORK FRYINGPAN RIVER NEAR NORRIE, CO.	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
FRYINGPAN RIVER AT MEREDITH, CO.	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
MAROON CREEK NEAR ASPEN, CO.	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 4 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	121	yes, 20 or more
Values held	3,649	yes, 1000 or more
Distinct measurements	6	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-09085000.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), Roaring Fork gauge records, accessed 2026-10-05, hydrionis.com/waters/united-states-roaring-fork/

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 Roaring Fork 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 confidence2025-06-03

Source: USGS — National Water Information System, USGS site 09085000, 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.