The monitoring network within this area

Hydrionis holds 3,823 values from 3 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.

3

Gauges

3,823

Values held

1913–2026

Record spans

Gauges within the Little Bear-Logan huc8 subbasin

3 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 BLACKSMITH FORK AB UP and L CO.'S DAM NR HYRUM, UT

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1914–2025.

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	BLACKSMITH FORK AB UP and L CO.'S DAM NR HYRUM, UT (m³/s)
1914	17.3
1916	28.9
1917	45.9
1919	8.18
1920	24.9
1921	27.6
1922	31.1
1925	10.3
1926	7.48
1927	20.9
1928	23.8
1929	13.2
1930	6.91
1932	22.3
1933	9.80
1935	9.29
1936	36.0
1937	19.1
1938	22.9
1939	5.89
1940	3.79
1941	3.00
1942	5.69
1943	17.3
1944	6.74
1945	11.8
1946	34.8
1947	8.64
1948	21.5
1949	15.2
1950	24.2
1951	17.6
1952	39.6
1953	8.75
1954	8.98
1955	12.9
1957	13.2
1958	14.6
1959	7.96
1960	9.00
1961	3.26
1962	23.5
1963	14.8
1964	13.4
1965	20.3
1966	4.02
1967	17.9
1968	10.5
1969	18.5
1970	11.6
1971	24.2
1972	20.1
1973	13.1
1974	21.9
1975	22.5
1976	13.9
1977	3.37
1978	11.8
1979	13.0
1980	19.3
1981	9.94
1982	41.3
1983	25.7
1984	46.7
1985	18.5
1986	24.0
1987	5.07
1988	3.77
1990	3.14
1991	16.5
1992	5.52
1993	13.5
1994	8.44
1995	11.1
1996	13.3
2000	7.56
2001	3.71
2002	4.45
2003	5.92
2004	4.50
2005	44.5
2006	22.2
2007	7.02
2008	9.74
2009	15.3
2010	4.93
2011	41.1
2012	6.26
2013	3.40
2014	8.10
2015	4.50
2016	9.94
2017	29.4
2018	6.06
2019	17.0
2020	7.99
2021	3.23
2022	4.33
2023	34.5
2024	15.2
2025	5.69

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	1914–2025
Completeness	90.2% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	8 separate periods inside 1914–2025 hold no value. The longest runs from 1997 to 1999 — 3 years with no reading. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1914 and is not continuous from it: 112 years separate the first value from the last, and 90% 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 BLACKSMITH FORK AB UP and L CO.'S DAM NR HYRUM, UT, as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1915–2025.

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	BLACKSMITH FORK AB UP and L CO.'S DAM NR HYRUM, UT (mm)
1915	114
1916	224
1917	278
1919	128
1920	210
1921	286
1922	252
1923	250
1924	156
1925	156
1926	117
1927	165
1928	164
1929	161
1930	114
1931	73.0
1932	196
1933	132
1934	68.0
1935	98.0
1936	210
1937	156
1938	161
1939	106
1940	79.0
1941	69.0
1942	84.0
1943	161
1944	106
1945	136
1946	233
1947	140
1948	188
1949	179
1950	264
1951	244
1952	268
1953	154
1954	120
1955	133
1956	199
1957	188
1958	172
1959	118
1960	119
1961	75.0
1962	161
1963	112
1964	138
1965	214
1966	140
1967	191
1968	152
1969	172
1970	146
1971	310
1972	308
1973	183
1974	234
1975	212
1976	181
1977	83.0
1978	163
1979	141
1980	201
1981	103
1982	255
1983	290
1984	392
1985	240
1986	360
1987	139
1988	96.0
1989	111
1990	71.0
1991	94.0
1992	66.0
1993	166
1994	111
1995	172
2001	90.0
2002	89.0
2003	82.0
2004	76.0
2005	171
2006	201
2007	99.0
2008	124
2009	145
2010	102
2011	339
2012	125
2013	84.0
2014	109
2015	79.0
2016	116
2017	298
2018	126
2019	174
2020	128
2021	74.0
2022	80.0
2023	219
2024	170
2025	101

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	1915–2025
Completeness	94.6% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	2 separate periods inside 1915–2025 hold no value. The longest runs from 1996 to 2000 — 5 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 95% 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

The snow standing above this water

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

1,020

Fullest snowpack recorded at Dry Bread Pond, in 1986 (mm of water)

210

Thinnest, in 1992 (mm of water)

March

Month the pack is usually at its fullest

June

Month the pack has gone by, in half of years

Peak snowpack at Dry Bread Pond

Water years 1979–2026. 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	Dry Bread Pond (mm)
1979	788
1980	671
1981	212
1982	698
1983	743
1984	742
1985	655
1986	1,020
1987	357
1988	431
1989	696
1990	302
1991	339
1992	210
1993	468
1994	371
1995	462
1996	505
1997	773
1998	487
1999	431
2000	363
2001	280
2002	310
2003	269
2004	361
2005	530
2006	596
2007	301
2008	600
2009	496
2010	289
2011	862
2012	343
2013	305
2014	419
2015	216
2016	459
2017	731
2018	312
2019	635
2020	464
2021	339
2022	340
2023	854
2024	461
2025	447
2026	248

Why the snow is not read against the river here

These two series do not overlap in time: Peak snow water equivalent runs 1978–2026 and Mean river flow, water year runs 1913–1969.

Every gauge Hydrionis holds within this area

Gauges within the Little Bear-Logan and what each holds
Gauge	Measures	Values	Record
BLACKSMITH FORK AB UP and L CO.'S DAM NR HYRUM, UT	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	352	1914–2026
COM F LOGAN R AB ST D AND CACHE HL CAN NR LOGAN UT	burned area within 50 km, catchment area, mean river flow, mean river flow, water year	245	1921–2026
UTAH POWER AND LIGHT TAILRACE NR LOGAN UTAH	burned area within 50 km, mean river flow, mean river flow, water year	144	1913–2019

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 — 16010203. 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
BLACKSMITH FORK AB UP and L CO.'S DAM NR HYRUM, UT	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
COM F LOGAN R AB ST D AND CACHE HL CAN NR LOGAN UT	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
UTAH POWER AND LIGHT TAILRACE NR LOGAN UTAH	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 5 of them, which makes it a full profile.

Information-gain signals held for this water body
Signal	Held	Counts
Gauges holding a real record	3	yes, 3 or more
Years spanned	114	yes, 20 or more
Values held	3,823	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-10113500.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), Little Bear-Logan gauge records, accessed 2026-10-05, hydrionis.com/waters/united-states-little-bear-logan/

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 Little Bear-Logan 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 confidence2025-04-13

Source: USGS — National Water Information System, USGS site 10113500, 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.