The monitoring network within this area

Hydrionis holds 2,856 values from 11 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

2,856

Values held

1913–2026

Record spans

Gauges within the Oahu huc8 subbasin

11 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 Kalihi Str nr Honolulu, Oahu, HI

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1917–2025.

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	Kalihi Str nr Honolulu, Oahu, HI (m³/s)
1917	17.5
1918	17.4
1920	24.9
1921	180
1923	172
1924	30.3
1925	42.5
1927	68.2
1928	33.4
1930	73.9
1932	184
1933	32.8
1934	24.9
1935	113
1936	45.0
1937	112
1939	79.0
1941	19.2
1942	29.7
1943	42.5
1944	5.07
1946	5.13
1947	24.5
1949	71.9
1950	81.0
1951	102
1952	55.5
1954	8.75
1955	53.0
1956	38.2
1957	11.6
1958	14.2
1960	123
1961	30.0
1963	79.9
1965	65.7
1967	34.0
1969	67.7
1970	66.5
1972	41.6
1973	3.88
1974	31.1
1975	23.3
1977	30.3
1978	8.95
1979	20.2
1980	74.5
1981	28.6
1982	145
1984	6.17
1985	31.1
1986	22.1
1987	61.2
1989	30.6
1990	80.4
1992	26.2
1994	50.7
1995	31.1
1996	30.0
1997	22.1
1999	16.3
2000	20.0
2002	49.8
2003	24.5
2004	113
2005	63.1
2006	23.4
2008	34.5
2009	22.8
2011	19.4
2013	27.3
2014	32.0
2015	17.0
2016	76.7
2017	11.2
2018	60.6
2020	13.7
2021	10.4
2023	11.5
2025	16.3

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	1917–2025
Completeness	73.4% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	29 separate periods inside 1917–2025 hold no value. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1917 and is not continuous from it: 109 years separate the first value from the last, and 73% 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 Kalihi Str nr Honolulu, Oahu, HI, as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1915–2025.

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	Kalihi Str nr Honolulu, Oahu, HI (mm)
1915	1,088
1916	1,294
1917	754
1918	1,495
1919	633
1920	698
1921	1,323
1922	1,036
1923	1,818
1924	767
1925	646
1926	415
1927	2,182
1928	835
1929	851
1930	1,549
1931	997
1932	1,432
1933	667
1934	1,014
1935	1,006
1936	1,163
1937	1,643
1938	1,282
1939	1,313
1940	735
1941	690
1942	1,261
1943	722
1944	494
1945	284
1946	485
1947	1,018
1948	862
1949	591
1950	886
1951	1,009
1952	925
1953	241
1954	882
1955	1,057
1956	932
1957	520
1958	1,104
1959	444
1960	844
1961	591
1962	388
1963	1,114
1964	1,048
1965	1,337
1966	633
1967	1,141
1968	980
1969	1,196
1970	741
1971	673
1972	498
1973	554
1974	858
1975	535
1976	404
1977	463
1978	694
1979	738
1980	1,249
1981	607
1982	1,643
1983	334
1984	219
1985	524
1986	799
1987	874
1988	941
1989	1,103
1990	1,055
1991	849
1992	669
1993	474
1994	979
1995	543
1996	624
1997	827
1998	334
1999	520
2000	494
2001	354
2002	714
2003	568
2004	1,148
2005	857
2006	1,065
2007	514
2008	571
2009	668
2010	589
2011	707
2012	556
2013	781
2014	850
2015	991
2016	936
2017	440
2018	1,535
2019	454
2020	481
2021	706
2022	311
2023	684
2024	550
2025	458

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	1915–2025
Completeness	100.0% of the periods in that span are held.
Continuity	Continuous: every year from 1915 to 2025 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

Every gauge Hydrionis holds within this area

Gauges within the Oahu and what each holds
Gauge	Measures	Values	Record
Kalihi Str nr Honolulu, Oahu, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	368	1914–2026
Waiakeakua Str at Honolulu, Oahu, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	357	1913–2026
NF Kaukonahua Str abv RB, nr Wahiawa, Oahu, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	341	1913–2026
Nuuanu Str bl Res 2 Wasteway nr Honolulu, Oahu, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	296	1914–2026
Heeia Stream at Haiku Valley nr Kaneohe, Oahu, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	276	1915–2026
Waihi Stream at Honolulu, Oahu, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	268	1913–2026
Pukele Stream near Honolulu, Oahu, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	249	1926–2026
Makawao Str nr Kailua, Oahu, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	234	1913–2026
Moanalua Str nr Honolulu, Oahu, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	213	1926–2026
N. Halawa Str nr Aiea, Oahu, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	205	1929–2026
Waiomao Stream near Honolulu, Oahu, HI	catchment area, annual maximum river flow	49	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 — 20060000. 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
Kalihi Str nr Honolulu, Oahu, HI	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
Waiakeakua Str at Honolulu, Oahu, HI	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 Kaukonahua Str abv RB, nr Wahiawa, Oahu, HI	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
Nuuanu Str bl Res 2 Wasteway nr Honolulu, Oahu, HI	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
Heeia Stream at Haiku Valley nr Kaneohe, Oahu, HI	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
Waihi Stream at Honolulu, Oahu, HI	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
Pukele Stream near Honolulu, Oahu, HI	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
Makawao Str nr Kailua, Oahu, HI	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
Moanalua Str nr Honolulu, Oahu, HI	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
N. Halawa Str nr Aiea, Oahu, HI	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
Waiomao Stream near Honolulu, Oahu, HI	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	10	yes, 3 or more
Years spanned	114	yes, 20 or more
Values held	2,856	yes, 1000 or more
Distinct measurements	5	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-16229000.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), Oahu gauge records, accessed 2026-10-05, hydrionis.com/waters/united-states-oahu/

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 Oahu 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 confidence2025-04-17

Source: USGS — National Water Information System, USGS site 16229000, 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.