The monitoring network within this area

Hydrionis holds 546 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

546

Values held

1896–2026

Record spans

Gauges within the Lake Washington 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 CEDAR RIVER NEAR LANDSBURG, WA

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1896–2025.

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	CEDAR RIVER NEAR LANDSBURG, WA (m³/s)
1896	96.8
1897	142
1901	107
1903	289
1904	57.2
1905	58.9
1906	57.2
1908	144
1909	70.2
1910	128
1911	402
1913	107
1915	37.7
1916	74.5
1917	63.4
1919	89.5
1920	52.7
1921	54.4
1923	118
1924	87.8
1925	77.6
1926	48.7
1927	51.5
1928	138
1929	33.4
1930	38.2
1931	34.0
1932	138
1933	122
1935	118
1936	53.8
1937	51.0
1939	42.5
1940	53.2
1941	51.8
1942	60.6
1944	39.1
1945	55.8
1946	119
1947	54.9
1949	49.6
1950	86.4
1951	176
1952	49.3
1953	95.4
1955	77.0
1956	91.7
1958	44.5
1959	98.0
1961	66.5
1963	54.7
1964	66.3
1965	131
1966	39.1
1967	61.4
1968	63.4
1970	45.9
1971	63.4
1972	109
1974	78.4
1975	65.7
1977	35.4
1979	45.0
1981	64.6
1982	113
1983	64.0
1984	113
1985	45.3
1986	116
1988	46.7
1989	47.9
1990	99.7
1991	46.2
1993	42.2
1994	33.1
1995	67.7
1997	59.2
1998	46.2
1999	75.3
2001	31.4
2002	63.4
2003	49.0
2004	59.2
2005	53.0
2006	83.5
2008	76.5
2009	223
2010	46.2
2011	133
2012	65.1
2013	48.1
2014	86.1
2015	70.5
2017	49.6
2018	60.0
2020	215
2021	70.5
2022	89.2
2023	33.4
2025	56.1

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	1896–2025
Completeness	76.9% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	28 separate periods inside 1896–2025 hold no value. The longest runs from 1898 to 1900 — 3 years with no reading. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1896 and is not continuous from it: 130 years separate the first value from the last, and 77% 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 CEDAR RIVER NEAR LANDSBURG, 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. 1896–2024.

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	CEDAR RIVER NEAR LANDSBURG, WA (mm)
1896	2,778
1897	2,849
1902	1,944
1903	2,178
1904	1,806
1905	1,647
1906	2,112
1907	1,752
1908	1,914
1909	2,205
1910	2,048
1911	1,801
1912	1,936
1913	2,075
1914	1,797
1915	1,443
1916	2,434
1917	2,844
1918	2,294
1919	2,008
1920	1,955
1921	2,343
1922	1,509
1923	1,824
1924	1,673
1925	1,705
1926	1,422
1927	2,210
1928	1,705
1929	1,389
1930	1,359
1931	1,450
1932	2,550
1933	2,818
1934	2,019
1935	1,670
1936	1,758
1937	1,860
1938	1,518
1939	1,653
1940	1,406
1941	1,106
1942	1,708
1943	1,717
1944	1,239
1945	2,069
1946	2,204
1947	2,081
1948	2,209
1949	1,946
1950	2,583
1951	2,012
1952	1,369
1953	2,164
1954	2,063
1955	2,390
1956	2,394
1957	1,674
1958	1,962
1959	2,827
1960	2,068
1961	2,135
1962	1,728
1963	1,793
1964	2,451
1965	1,893
1966	1,874
1967	1,972
1968	2,266
1969	1,872
1970	1,826
1971	2,480
1972	2,759
1973	1,471
1974	2,490
1975	2,596
1976	1,916
1977	1,826
1978	1,554
1979	1,606
1980	1,725
1981	1,732
1982	2,091
1983	1,861
1984	2,031
1985	1,797
1986	1,840
1987	1,334
1988	1,711
1989	1,862
1990	2,675
1991	2,111
1992	1,268
1993	1,465
1994	1,518
1995	2,054
1996	2,264
1997	2,559
1998	1,758
1999	2,428
2000	1,620
2001	1,508
2002	1,900
2003	1,697
2004	1,682
2005	1,338
2006	2,222
2007	1,756
2008	2,071
2009	2,012
2010	1,866
2011	2,574
2012	2,535
2013	2,072
2014	2,328
2015	1,841
2016	1,905
2017	2,091
2018	2,096
2019	1,508
2020	2,524
2021	2,171
2022	2,228
2023	1,487
2024	1,542

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	1896–2024
Completeness	96.9% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	One period inside 1896–2024 holds no value: 1898 to 1901, 4 years with no reading. It is drawn as a break in the line and is never interpolated across.
Continuity	The record begins in 1896 and is not continuous from it: 129 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	2026-08-24
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 Lake Washington and what each holds
Gauge	Measures	Values	Record
CEDAR RIVER NEAR LANDSBURG, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	288	1896–2026
CEDAR RIVER AT CEDAR FALLS, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	258	1914–2026

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 — 17110012. 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
CEDAR RIVER NEAR LANDSBURG, 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	2026-08-26
CEDAR RIVER AT CEDAR 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	2026-08-26

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	131	yes, 20 or more
Values held	546	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-12117500.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), Lake Washington gauge records, accessed 2026-09-02, hydrionis.com/waters/united-states-lake-washington/

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 Lake Washington 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 confidence2025-02-23

Source: USGS — National Water Information System, USGS site 12117500, 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.