The monitoring network within this area

Hydrionis holds 1,547 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.

2
Gauges
1,547
Values held
1911–2026
Record spans
Gauges within the Middle Bear huc8 subbasin
2 monitoring points, positioned as the publisher records them.
Gauges within the Middle Bear huc8 subbasinBEAR RIVER AT ALEXANDER ID, BEAR RIVER BELOW GRACE DAM, NEAR GRACE, IDBEAR RIVER AT ALEXANDER IDBEAR RIVER BELOW GRACE DAM, NEAR GRACE, ID

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 BEAR RIVER AT ALEXANDER ID
The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1916–2020.
Shading marks when something was recorded, not what caused the line.
Largest measured flow of each year at BEAR RIVER AT ALEXANDER IDLargest measured flow of each year at BEAR RIVER AT ALEXANDER ID: BEAR RIVER AT ALEXANDER ID in m³/s, from 1916 to 2020.Hurricane Katrina water and sanitation collapse50100150m³/s19161920195819641968197219781982BEAR RIVER AT ALEXANDER ID 1916: 61.4 m³/sBEAR RIVER AT ALEXANDER ID 1917: 130 m³/sBEAR RIVER AT ALEXANDER ID 1918: 39.6 m³/sBEAR RIVER AT ALEXANDER ID 1919: 36.2 m³/sBEAR RIVER AT ALEXANDER ID 1920: 43.0 m³/sBEAR RIVER AT ALEXANDER ID 1921: 110 m³/sBEAR RIVER AT ALEXANDER ID 1922: 130 m³/sBEAR RIVER AT ALEXANDER ID 1924: 69.1 m³/sBEAR RIVER AT ALEXANDER ID 1924: 69.7 m³/sBEAR RIVER AT ALEXANDER ID 1958: 61.4 m³/sBEAR RIVER AT ALEXANDER ID 1961: 70.2 m³/sBEAR RIVER AT ALEXANDER ID 1962: 66.0 m³/sBEAR RIVER AT ALEXANDER ID 1963: 88.6 m³/sBEAR RIVER AT ALEXANDER ID 1964: 49.3 m³/sBEAR RIVER AT ALEXANDER ID 1965: 65.1 m³/sBEAR RIVER AT ALEXANDER ID 1966: 75.3 m³/sBEAR RIVER AT ALEXANDER ID 1967: 59.5 m³/sBEAR RIVER AT ALEXANDER ID 1968: 62.0 m³/sBEAR RIVER AT ALEXANDER ID 1969: 46.2 m³/sBEAR RIVER AT ALEXANDER ID 1970: 45.6 m³/sBEAR RIVER AT ALEXANDER ID 1971: 101 m³/sBEAR RIVER AT ALEXANDER ID 1972: 67.1 m³/sBEAR RIVER AT ALEXANDER ID 1972: 63.1 m³/sBEAR RIVER AT ALEXANDER ID 1974: 64.8 m³/sBEAR RIVER AT ALEXANDER ID 1974: 54.4 m³/sBEAR RIVER AT ALEXANDER ID 1976: 59.5 m³/sBEAR RIVER AT ALEXANDER ID 1977: 46.4 m³/sBEAR RIVER AT ALEXANDER ID 1978: 56.4 m³/sBEAR RIVER AT ALEXANDER ID 1979: 50.7 m³/sBEAR RIVER AT ALEXANDER ID 1980: 66.0 m³/sBEAR RIVER AT ALEXANDER ID 1981: 46.2 m³/sBEAR RIVER AT ALEXANDER ID 1982: 53.8 m³/sBEAR RIVER AT ALEXANDER ID 2018: 60.9 m³/sBEAR RIVER AT ALEXANDER ID 2019: 41.9 m³/sBEAR RIVER AT ALEXANDER ID 2020: 137 m³/s

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.

EventTypePeriodStandingAuthority
Hurricane Katrina water and sanitation collapseFlood2005-08-29 – 2005-09-30Documented 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
PeriodBEAR RIVER AT ALEXANDER ID (m³/s)
191661.4
1917130
191839.6
191936.2
192043.0
1921110
1922130
192469.1
195861.4
196170.2
196266.0
196388.6
196449.3
196565.1
196675.3
196759.5
196862.0
196946.2
197045.6
1971101
197267.1
197464.8
197659.5
197746.4
197856.4
197950.7
198066.0
198146.2
198253.8
201860.9
201941.9
2020137

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 existMeasured
Period held1916–2020
Completeness30.5% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps
  • 6 separate periods inside 1916–2020 hold no value. The longest runs from 1983 to 2017 — 35 years with no reading. They are drawn as breaks in the line and are never interpolated across.
ContinuityThe record begins in 1916 and is not continuous from it: 105 years separate the first value from the last, and 30% of the years between them are held. The span is not the record.
Last read from the publisher2026-10-01
RedistributionPermitted by the upstream licences
Commercial reusePermitted by the upstream licences. No Hydrionis access tier can widen this.
MethodologyHow 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 BEAR RIVER AT ALEXANDER ID, as a depth
The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1912–2019.
Shading marks when something was recorded, not what caused the line.
Water leaving the catchment above BEAR RIVER AT ALEXANDER ID, as a depthWater leaving the catchment above BEAR RIVER AT ALEXANDER ID, as a depth: BEAR RIVER AT ALEXANDER ID in mm, from 1912 to 2019.Hurricane Katrina water and sanitation collapse050100150200mm19121930194219541966197819902002

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.

EventTypePeriodStandingAuthority
Hurricane Katrina water and sanitation collapseFlood2005-08-29 – 2005-09-30Documented 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
PeriodBEAR RIVER AT ALEXANDER ID (mm)
1912104
1914122
192078.0
192195.0
1922128
1923128
192493.0
192572.0
192679.0
192765.0
192860.0
192956.0
193051.0
193141.0
193234.0
193338.0
193438.0
193532.0
193639.0
193735.0
193843.0
193940.0
194038.0
194136.0
194241.0
194349.0
194438.0
194539.0
194655.0
194767.0
194866.0
194961.0
1950109
1951106
195295.0
195359.0
195443.0
195541.0
195649.0
195758.0
195854.0
195939.0
196045.0
196142.0
196244.0
196342.0
196444.0
196574.0
196665.0
196767.0
196849.0
196959.0
197044.0
1971125
1972119
197383.0
197483.0
197587.0
197680.0
197749.0
197846.0
197944.0
198090.0
198147.0
198280.0
1983164
1984169
1985100
1986180
198757.0
198847.0
198942.0
199046.0
199138.0
199241.0
199339.0
199444.0
199539.0
199647.0
1997104
1998111
1999102
200058.0
200145.0
200241.0
200338.0
200428.0
200540.0
201441.0
201542.0
201648.0
201778.0
201866.0
201949.0

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 existDerived Computed by Hydrionis
Period held1912–2019
Completeness87.0% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps
  • 3 separate periods inside 1912–2019 hold no value. The longest runs from 2006 to 2013 — 8 years with no reading. They are drawn as breaks in the line and are never interpolated across.
ContinuityThe record begins in 1912 and is not continuous from it: 108 years separate the first value from the last, and 87% of the years between them are held. The span is not the record.
Inputs last read2026-10-01 · when the records this was computed from were last read from their publishers
Calculation date2026-08-24 · when the calculation method was last versioned, not a reading of any publisher
RedistributionPermitted by the upstream licences
Commercial reusePermitted by the upstream licences. No Hydrionis access tier can widen this.
MethodologyHow this was produced

The snow standing above this water

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

1,228
Fullest snowpack recorded at Franklin Basin, in 2011 (mm of water)
344
Thinnest, in 1992 (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 Franklin Basin
Water years 1981–2026. Each point is the fullest month of that snow season.
Peak snowpack at Franklin BasinPeak snowpack at Franklin Basin: Franklin Basin in mm, from 1981 to 2026.05001,000mm19811987199319992005201120172023Franklin Basin 1981: 346 mmFranklin Basin 1982: 1,052 mmFranklin Basin 1983: 983 mmFranklin Basin 1984: 902 mmFranklin Basin 1985: 774 mmFranklin Basin 1986: 1,069 mmFranklin Basin 1987: 406 mmFranklin Basin 1988: 457 mmFranklin Basin 1989: 732 mmFranklin Basin 1990: 481 mmFranklin Basin 1991: 571 mmFranklin Basin 1992: 344 mmFranklin Basin 1993: 898 mmFranklin Basin 1994: 585 mmFranklin Basin 1995: 815 mmFranklin Basin 1996: 988 mmFranklin Basin 1997: 958 mmFranklin Basin 1998: 796 mmFranklin Basin 1999: 952 mmFranklin Basin 2000: 565 mmFranklin Basin 2001: 359 mmFranklin Basin 2002: 529 mmFranklin Basin 2003: 507 mmFranklin Basin 2004: 514 mmFranklin Basin 2005: 692 mmFranklin Basin 2006: 1,094 mmFranklin Basin 2007: 463 mmFranklin Basin 2008: 780 mmFranklin Basin 2009: 798 mmFranklin Basin 2010: 476 mmFranklin Basin 2011: 1,228 mmFranklin Basin 2012: 464 mmFranklin Basin 2013: 466 mmFranklin Basin 2014: 642 mmFranklin Basin 2015: 497 mmFranklin Basin 2016: 655 mmFranklin Basin 2017: 1,086 mmFranklin Basin 2018: 658 mmFranklin Basin 2019: 692 mmFranklin Basin 2020: 715 mmFranklin Basin 2021: 493 mmFranklin Basin 2022: 479 mmFranklin Basin 2023: 1,141 mmFranklin Basin 2024: 783 mmFranklin Basin 2025: 664 mmFranklin Basin 2026: 531 mm

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
PeriodFranklin Basin (mm)
1981346
19821,052
1983983
1984902
1985774
19861,069
1987406
1988457
1989732
1990481
1991571
1992344
1993898
1994585
1995815
1996988
1997958
1998796
1999952
2000565
2001359
2002529
2003507
2004514
2005692
20061,094
2007463
2008780
2009798
2010476
20111,228
2012464
2013466
2014642
2015497
2016655
20171,086
2018658
2019692
2020715
2021493
2022479
20231,141
2024783
2025664
2026531

Read against the river

Franklin Basin and BEAR RIVER AT ALEXANDER ID both sit in this drainage area, and their records overlap by 39 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 Middle Bear and what each holds
GaugeMeasuresValuesRecord
BEAR RIVER AT ALEXANDER IDburned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year2621911–2026
BEAR RIVER BELOW GRACE DAM, NEAR GRACE, IDburned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year1951926–2026

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 — 16010202. 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
GaugeEvidenceEstablished
BEAR RIVER AT ALEXANDER IDStated 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/42026-10-02
BEAR RIVER BELOW GRACE DAM, NEAR GRACE, IDStated 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/42026-10-02

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
SignalHeldCounts
Gauges holding a real record2no
Years spanned116yes, 20 or more
Values held1,547yes, 1000 or more
Distinct measurements6yes, 2 or more
Publishers measuring it2yes, 2 or more
Official identifiers1recorded, not counted

Use this data

Use this data

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 Bear gauge records, accessed 2026-10-05, hydrionis.com/waters/united-states-middle-bear/

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 Bear 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 confidence2020-07-22

Source: USGS — National Water Information System, USGS site 10079500, 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.