The monitoring network within this area

Hydrionis holds 2,068 values from 8 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.

8

Gauges

2,068

Values held

1878–2026

Record spans

Gauges within the Lower Yakima huc8 subbasin

8 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 YAKIMA RIVER AT KIONA, WA

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1878–2025.

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	YAKIMA RIVER AT KIONA, WA (m³/s)
1878	236
1896	1,076
1898	654
1899	464
1900	538
1901	748
1902	479
1903	748
1904	906
1905	374
1906	334
1908	470
1909	453
1910	385
1912	456
1913	592
1914	320
1933	1,897
1935	513
1936	399
1937	484
1938	439
1939	202
1940	251
1941	128
1943	379
1945	240
1946	433
1948	1,073
1949	439
1950	425
1951	592
1952	178
1953	326
1954	340
1955	518
1956	569
1957	555
1958	289
1959	306
1961	368
1962	320
1963	382
1964	246
1965	634
1966	193
1967	297
1968	430
1969	408
1970	234
1971	408
1972	572
1974	1,124
1975	365
1976	96.6
1977	765
1979	195
1980	368
1982	629
1983	484
1984	496
1985	206
1986	456
1987	236
1988	171
1989	238
1990	266
1992	173
1993	185
1994	125
1995	493
1996	1,399
1997	518
1998	396
1999	365
2000	85.8
2002	391
2003	527
2004	170
2005	283
2006	328
2007	490
2008	413
2009	719
2010	212
2011	716
2012	527
2013	314
2014	328
2015	340
2017	453
2018	354
2019	240
2020	498
2021	251
2022	388
2023	362
2024	283
2025	385

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	1878–2025
Completeness	66.9% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	16 separate periods inside 1878–2025 hold no value. The longest runs from 1915 to 1932 — 18 years with no reading. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1878 and is not continuous from it: 148 years separate the first value from the last, and 67% 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 YAKIMA RIVER AT KIONA, 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. 1934–2025.

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	YAKIMA RIVER AT KIONA, WA (mm)
1934	300
1935	222
1936	202
1937	183
1938	249
1939	128
1940	148
1941	119
1942	125
1943	227
1944	96.0
1945	129
1946	244
1947	231
1948	280
1949	286
1950	338
1951	304
1952	156
1953	200
1954	267
1955	235
1956	402
1957	212
1958	213
1959	294
1960	188
1961	256
1962	197
1963	178
1964	166
1965	245
1966	146
1967	186
1968	212
1969	233
1970	163
1971	268
1972	418
1973	131
1974	353
1975	313
1976	252
1977	121
1978	222
1979	108
1980	230
1981	175
1982	262
1983	286
1984	238
1985	144
1986	183
1987	134
1988	124
1989	155
1990	217
1991	196
1992	126
1993	125
1994	103
1995	315
1996	339
1997	391
1998	230
1999	296
2000	195
2001	95.0
2002	195
2003	194
2004	157
2006	216
2007	224
2008	174
2009	222
2010	180
2011	291
2012	283
2013	212
2014	228
2015	186
2016	267
2017	278
2018	211
2019	154
2020	173
2022	218
2023	166
2024	137
2025	179

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	1934–2025
Completeness	97.8% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	2 separate periods inside 1934–2025 hold no value. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1934 and is not continuous from it: 92 years separate the first value from the last, and 98% 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

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

1,074

Fullest snowpack recorded at Green Lake, in 1997 (mm of water)

212

Thinnest, in 2015 (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 Green Lake

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	Green Lake (mm)
1983	887
1984	497
1985	333
1986	446
1987	505
1988	555
1989	605
1990	414
1991	476
1992	400
1993	536
1994	442
1995	719
1996	524
1997	1,074
1998	642
1999	1,063
2000	592
2001	357
2002	650
2003	544
2004	565
2005	234
2006	879
2007	605
2008	736
2009	675
2010	642
2011	698
2012	945
2013	620
2014	576
2015	212
2016	738
2017	662
2018	531
2019	557
2020	509
2021	643
2022	509
2023	726
2024	511
2025	640
2026	431

Why the snow is not read against the river here

These two series do not overlap in time: Peak snow water equivalent runs 1982–2026 and Mean river flow, water year runs 1910–1977.

Every gauge Hydrionis holds within this area

Gauges within the Lower Yakima and what each holds
Gauge	Measures	Values	Record
YAKIMA RIVER AT KIONA, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	328	1878–2026
YAKIMA RIVER NEAR PARKER, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	246	1908–2026
AHTANUM CREEK AT UNION GAP, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	234	1908–2026
NORTH FORK AHTANUM CREEK NEAR TAMPICO, WA	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	200	1908–2026
SF AHTANUM CREEK AT CONRAD RANCH NR TAMPICO, WA	catchment area, annual maximum river flow	58	1915–2026
TOPPENISH CREEK NEAR FORT SIMCOE, WA	catchment area, annual maximum river flow	28	1910–2026
AHTANUM CREEK AT THE NARROWS NEAR TAMPICO, WA	catchment area, annual maximum river flow	13	1909–2026
YAKIMA RIVER AT UNION GAP NEAR YAKIMA, WA	catchment area	1	2026–2026

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 — 17030003. 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
YAKIMA RIVER AT KIONA, 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
YAKIMA RIVER NEAR PARKER, 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
AHTANUM CREEK AT UNION GAP, 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 AHTANUM CREEK NEAR TAMPICO, 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 AHTANUM CREEK AT CONRAD RANCH NR TAMPICO, 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
TOPPENISH CREEK NEAR FORT SIMCOE, 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
AHTANUM CREEK AT THE NARROWS NEAR TAMPICO, 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
YAKIMA RIVER AT UNION GAP NEAR YAKIMA, 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	149	yes, 20 or more
Values held	2,068	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-12510500.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), Lower Yakima gauge records, accessed 2026-10-05, hydrionis.com/waters/united-states-lower-yakima/

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 Lower Yakima 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 confidence2025-03-29

Source: USGS — National Water Information System, USGS site 12510500, 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.