The monitoring network within this area

Hydrionis holds 2,766 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

2,766

Values held

1908–2026

Record spans

Gauges within the Snoqualmie 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 SNOQUALMIE RIVER NEAR CARNATION, WA

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1929–2023.

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	SNOQUALMIE RIVER NEAR CARNATION, WA (m³/s)
1929	419
1931	776
1932	1,685
1933	1,379
1934	1,334
1936	456
1937	487
1938	1,099
1939	535
1940	566
1941	558
1942	858
1943	1,371
1945	906
1946	923
1947	702
1948	572
1950	852
1951	1,478
1952	405
1953	917
1955	716
1956	779
1958	436
1959	883
1961	793
1962	578
1964	493
1965	1,178
1966	351
1967	1,229
1969	1,433
1970	379
1971	597
1972	1,184
1974	1,065
1975	1,368
1977	521
1979	467
1980	1,113
1982	1,113
1984	1,206
1985	524
1986	816
1987	470
1988	906
1990	1,385
1992	510
1993	787
1995	1,184
1996	1,744
1997	1,274
1998	1,070
1999	994
2000	462
2001	736
2003	731
2005	1,399
2006	663
2007	909
2009	2,347
2011	1,461
2012	937
2014	1,031
2015	1,526
2017	575
2018	569
2020	1,393
2021	714
2022	1,328
2023	858

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	1929–2023
Completeness	74.7% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	24 separate periods inside 1929–2023 hold no value. 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: 95 years separate the first value from the last, and 75% 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 SNOQUALMIE RIVER NEAR CARNATION, WA, as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1930–2023.

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	SNOQUALMIE RIVER NEAR CARNATION, WA (mm)
1930	1,485
1931	1,893
1932	3,192
1933	3,193
1934	2,231
1935	1,744
1936	1,995
1937	2,249
1938	1,745
1939	2,115
1940	1,614
1941	1,556
1942	1,855
1943	1,879
1944	1,605
1945	2,312
1946	2,434
1947	2,548
1948	2,365
1949	2,261
1950	2,972
1951	2,053
1952	1,392
1953	2,692
1954	2,266
1955	2,763
1956	2,570
1957	1,683
1958	2,149
1959	3,067
1960	2,055
1961	2,369
1962	2,045
1963	1,749
1964	2,664
1965	1,965
1966	2,060
1967	2,186
1968	2,373
1969	2,051
1970	1,874
1971	2,594
1972	3,032
1973	1,623
1974	2,639
1975	2,793
1976	1,992
1977	2,032
1978	1,678
1979	1,814
1980	1,997
1981	1,921
1982	2,303
1983	2,009
1984	2,190
1985	1,831
1986	1,790
1987	1,267
1988	2,031
1989	2,053
1990	2,774
1991	2,085
1992	1,443
1993	1,687
1994	1,727
1995	2,471
1996	2,335
1997	2,760
1998	1,909
1999	2,585
2000	1,699
2001	1,798
2002	1,998
2003	1,907
2004	1,945
2005	1,593
2006	2,111
2007	2,068
2008	2,184
2009	2,140
2010	1,997
2011	2,583
2012	2,406
2013	2,148
2014	2,466
2015	1,987
2016	2,031
2017	2,125
2018	2,126
2019	1,631
2020	2,676
2021	2,302
2022	2,226
2023	1,540

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	1930–2023
Completeness	100.0% of the periods in that span are held.
Continuity	Continuous: every year from 1930 to 2023 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

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

2,457

Fullest snowpack recorded at Olallie Meadows, in 1997 (mm of water)

231

Thinnest, in 2015 (mm of water)

April

Month the pack is usually at its fullest

July

Month the pack has gone by, in half of years

Peak snowpack at Olallie Meadows

Water years 1983–2026. 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	Olallie Meadows (mm)
1983	1,271
1984	1,398
1985	1,728
1986	911
1987	1,201
1988	1,401
1989	1,450
1990	1,420
1991	1,299
1992	713
1993	917
1994	1,011
1995	1,174
1996	828
1997	2,457
1998	1,345
1999	2,311
2000	1,508
2001	895
2002	1,806
2003	1,039
2004	1,176
2005	439
2006	1,695
2007	1,500
2008	2,132
2009	1,480
2010	1,281
2011	1,623
2012	1,959
2013	1,461
2014	1,400
2015	231
2016	1,279
2017	1,451
2018	1,500
2019	869
2020	1,205
2022	1,356
2023	1,471
2024	1,055
2025	1,069
2026	577

Read against the river

Olallie Meadows and NF SNOQUALMIE RIVER NEAR SNOQUALMIE FALLS, WA both sit in this drainage area, and their records overlap by 42 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 Snoqualmie and what each holds
Gauge	Measures	Values	Record
SNOQUALMIE RIVER NEAR CARNATION, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	321	1929–2026
TOLT RIVER NEAR CARNATION, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	309	1928–2026
NF SNOQUALMIE RIVER NEAR SNOQUALMIE FALLS, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	293	1929–2026
SF SNOQUALMIE RIVER AT NORTH BEND, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	286	1908–2026
SNOQUALMIE RIVER NEAR SNOQUALMIE, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	237	1958–2026
NORTH FORK SNOQUALMIE RIVER NEAR NORTH BEND, WA	catchment area, annual maximum river flow	44	1909–2026

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 — 17110010. 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
SNOQUALMIE RIVER NEAR CARNATION, WA	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
TOLT RIVER NEAR CARNATION, WA	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
NF SNOQUALMIE RIVER NEAR SNOQUALMIE FALLS, WA	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
SF SNOQUALMIE RIVER AT NORTH BEND, WA	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
SNOQUALMIE RIVER NEAR SNOQUALMIE, WA	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 SNOQUALMIE RIVER NEAR NORTH BEND, WA	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	5	yes, 3 or more
Years spanned	119	yes, 20 or more
Values held	2,766	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-12149000.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), Snoqualmie gauge records, accessed 2026-10-05, hydrionis.com/waters/united-states-snoqualmie/

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 Snoqualmie 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 confidence2023-12-06

Source: USGS — National Water Information System, USGS site 12149000, 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.