The monitoring network within this area

Hydrionis holds 376 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

376

Values held

1927–2026

Record spans

Gauges within the Willapa Bay 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 NASELLE RIVER NEAR NASELLE, WA

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1929–2024.

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	NASELLE RIVER NEAR NASELLE, WA (m³/s)
1929	69.7
1931	81.0
1932	142
1933	214
1935	314
1936	176
1937	101
1939	148
1941	123
1942	164
1943	199
1945	184
1946	164
1948	131
1949	292
1950	162
1951	193
1952	163
1953	195
1954	159
1955	170
1956	198
1958	101
1959	150
1961	201
1962	297
1964	159
1966	98.5
1968	158
1970	142
1972	203
1973	104
1974	126
1975	215
1977	106
1979	142
1981	162
1982	212
1983	144
1984	102
1986	189
1987	170
1988	113
1990	265
1992	156
1993	72.5
1994	294
1996	221
1997	357
1998	186
1999	266
2001	71.1
2003	157
2005	155
2006	196
2007	203
2009	382
2011	160
2012	170
2014	128
2015	268
2016	160
2017	181
2018	175
2020	215
2021	193
2022	309
2023	200
2024	159

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	1929–2024
Completeness	71.9% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	27 separate periods inside 1929–2024 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: 96 years separate the first value from the last, and 72% 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 NASELLE RIVER NEAR NASELLE, 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. 1930–2025.

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	NASELLE RIVER NEAR NASELLE, WA (mm)
1930	1,787
1931	3,106
1932	3,621
1933	4,078
1934	2,907
1935	2,312
1936	2,284
1937	3,309
1938	2,171
1939	2,478
1940	2,532
1941	2,150
1942	2,246
1943	2,107
1944	1,830
1945	2,973
1946	3,278
1947	2,627
1948	3,061
1949	2,421
1950	3,779
1951	2,845
1952	1,894
1953	3,242
1954	2,931
1955	3,138
1956	2,996
1957	2,230
1958	2,772
1959	3,075
1960	2,657
1961	3,239
1962	2,600
1963	2,273
1964	2,783
1965	2,178
1966	2,665
1967	2,749
1968	3,327
1969	2,361
1970	2,828
1971	3,278
1972	3,172
1973	2,604
1974	3,169
1975	3,317
1976	1,887
1977	2,607
1978	1,985
1979	2,441
1980	2,356
1981	2,568
1982	3,180
1983	3,140
1984	2,782
1985	1,866
1986	2,478
1987	2,128
1988	2,314
1989	2,307
1990	3,416
1991	2,494
1992	1,822
1993	1,928
1994	3,160
1995	3,157
1996	3,113
1997	3,477
1998	3,262
1999	3,579
2000	1,684
2001	2,590
2002	2,177
2003	2,831
2004	1,924
2005	2,051
2006	3,077
2007	2,461
2008	2,242
2009	2,592
2010	2,926
2011	2,889
2012	3,656
2013	2,105
2014	3,138
2015	2,799
2016	3,472
2017	3,435
2018	2,710
2019	1,703
2020	3,322
2021	3,248
2022	2,999
2023	2,381
2024	3,064
2025	2,906

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	1930–2025
Completeness	100.0% of the periods in that span are held.
Continuity	Continuous: every year from 1930 to 2025 is held.
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 Willapa Bay and what each holds
Gauge	Measures	Values	Record
NASELLE RIVER NEAR NASELLE, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	229	1929–2026
NORTH RIVER NEAR RAYMOND, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow	147	1927–2026

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 — 17100106. 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
NASELLE RIVER NEAR NASELLE, 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
NORTH RIVER NEAR RAYMOND, 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	100	yes, 20 or more
Values held	376	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-12010000.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), Willapa Bay gauge records, accessed 2026-09-02, hydrionis.com/waters/united-states-willapa-bay/

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 Willapa Bay 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 confidence2024-12-18

Source: USGS — National Water Information System, USGS site 12010000, 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.