The monitoring network within this area

Hydrionis holds 4,014 values from 22 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

4,014

Values held

1910–2026

Record spans

Gauges within the Maui huc8 subbasin

22 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 Honopou Stream near Huelo, Maui, HI

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1911–2025.

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	Honopou Stream near Huelo, Maui, HI (m³/s)
1911	3.68
1912	2.18
1914	2.80
1916	21.0
1917	9.29
1918	17.3
1919	3.77
1921	17.3
1922	75.0
1923	34.3
1924	12.9
1926	21.0
1927	18.7
1928	4.33
1930	8.55
1932	31.4
1934	8.10
1935	7.45
1936	10.5
1938	12.5
1939	39.1
1940	13.6
1941	27.2
1942	15.8
1944	2.46
1946	20.6
1948	36.2
1950	60.6
1952	8.86
1953	31.1
1954	9.63
1955	6.80
1956	47.9
1957	12.5
1958	7.99
1960	29.2
1961	5.83
1962	22.7
1963	21.4
1964	6.34
1965	44.7
1967	12.0
1968	11.6
1969	10.8
1971	58.0
1972	5.86
1973	8.07
1974	13.1
1976	6.06
1977	4.39
1978	21.2
1980	15.2
1981	5.49
1982	73.6
1984	10.6
1985	5.41
1987	41.3
1988	10.1
1989	67.7
1990	49.3
1991	58.0
1992	23.3
1993	8.98
1994	35.7
1996	38.2
1997	85.8
1999	33.4
2001	8.21
2002	9.63
2004	84.4
2005	28.3
2006	8.66
2008	28.3
2009	10.3
2010	18.5
2012	23.6
2013	32.0
2014	17.6
2016	56.9
2018	126
2020	34.3
2021	214
2023	26.6
2024	9.29
2025	19.2

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	1911–2025
Completeness	73.9% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	30 separate periods inside 1911–2025 hold no value. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1911 and is not continuous from it: 115 years separate the first value from the last, and 74% 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 Honopou Stream near Huelo, Maui, 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. 1912–2025.

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	Honopou Stream near Huelo, Maui, HI (mm)
1912	2,315
1913	2,700
1914	5,961
1915	3,425
1916	4,758
1917	1,221
1918	4,862
1919	1,718
1920	2,033
1921	3,740
1922	3,349
1923	3,483
1924	2,760
1925	2,168
1926	1,414
1927	3,465
1928	2,660
1929	3,284
1930	3,816
1931	2,542
1932	2,930
1933	1,286
1934	2,700
1935	1,958
1936	3,282
1937	4,535
1938	3,600
1939	3,191
1940	1,975
1941	3,699
1942	3,349
1943	2,028
1944	1,758
1945	1,256
1946	3,091
1947	2,647
1948	3,926
1949	1,572
1950	3,787
1951	1,619
1952	2,801
1953	1,046
1954	2,595
1955	2,723
1956	3,715
1957	3,267
1958	3,062
1959	2,449
1960	2,748
1961	1,952
1962	1,069
1963	2,227
1964	2,473
1965	2,776
1966	1,946
1967	2,811
1968	2,461
1969	4,944
1970	3,594
1971	1,847
1972	1,453
1973	1,981
1974	1,847
1975	1,724
1976	1,617
1977	2,203
1978	2,893
1979	2,805
1980	4,530
1981	1,554
1982	4,810
1983	1,847
1984	1,078
1985	2,706
1986	3,641
1987	3,547
1988	2,701
1989	5,143
1990	5,090
1991	3,132
1992	2,959
1993	2,916
1994	4,552
1995	1,800
1996	2,584
1997	3,430
1998	2,793
1999	2,618
2000	2,403
2001	1,882
2002	1,987
2003	1,847
2004	2,983
2005	3,214
2006	1,905
2007	1,391
2008	1,758
2009	2,191
2010	1,847
2011	1,514
2012	2,250
2013	1,964
2014	3,360
2015	4,254
2016	5,239
2017	2,525
2018	5,318
2019	2,285
2020	2,385
2021	4,681
2022	1,554
2023	2,057
2024	2,069
2025	1,034

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	1912–2025
Completeness	100.0% of the periods in that span are held.
Continuity	Continuous: every year from 1912 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 Maui and what each holds
Gauge	Measures	Values	Record
Honopou Stream near Huelo, Maui, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	378	1911–2026
Honokohau Stream near Honokohau, Maui, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	354	1913–2026
West Wailuaiki Stream near Keanae, Maui, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	352	1914–2026
Hanawi Stream near Nahiku, Maui, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	347	1914–2026
Nailiilihaele Stream near Huelo, Maui, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	219	1911–2026
HOOLAWANUI STREAM NR HUELO, MAUI, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	214	1911–2026
Puohokamoa Str ab Spreckels Ditch, Maui, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	208	1913–2026
Haipuaena Stream abv Spreckels Ditch, Maui, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	191	1914–2026
Honomanu Stream near Keanae, Maui, HI	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	184	1914–2026
Lowrie Ditch at Honopou Gulch near Huelo, Maui, HI	burned area within 50 km, mean river flow, mean river flow, water year	178	1910–2019
Haiku Ditch at Honopou Gulch near Kailua, Maui, HI	burned area within 50 km, mean river flow, mean river flow, water year	177	1910–2019
Koolau Ditch near Keanae, Maui, HI	burned area within 50 km, mean river flow, mean river flow, water year	173	1910–2019
New Hamakua Ditch at Honopou near Huelo, Maui, HI	burned area within 50 km, mean river flow, mean river flow, water year	169	1918–2019
KOOLAU DITCH AT NAHIKU WEIR NR NAHIKU, MAUI, HI	burned area within 50 km, mean river flow, mean river flow, water year	167	1919–2019
Manuel Luis Ditch at Puohokamoa Stream, Maui, HI	burned area within 50 km, mean river flow, mean river flow, water year	167	1918–2019
Wailoa Ditch at Honopou near Huelo, Maui, HI	burned area within 50 km, mean river flow, mean river flow, water year	164	1923–2019
SPRECKELS DITCH AT HAIPUAENA WEIR NR HUELO, MAUI	burned area within 50 km, mean river flow, mean river flow, water year	158	1922–2019
HONOKOWAI DITCH NEAR LAHAINA, MAUI, HI	burned area within 50 km, mean river flow, mean river flow, water year	137	1912–2019
PALIKEA STREAM BL DIV DAM NR KIPAHULU, MAUI, HI	catchment area, annual maximum river flow	54	1927–2026
M B PUOHOKAMOA STR AT HAIKU-UKA BDRY NR KAILIILI	catchment area, annual maximum river flow	16	1920–2026
Kauaula Stream US of ditch diversion, Maui, HI	catchment area, annual maximum river flow	4	2021–2026
Ukumehame Gulch nr Olowalu, Maui, HI	catchment area, annual maximum river flow	3	2023–2026

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 — 20020000. 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
Honopou Stream near Huelo, Maui, 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
Honokohau Stream near Honokohau, Maui, 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
West Wailuaiki Stream near Keanae, Maui, 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
Hanawi Stream near Nahiku, Maui, 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
Nailiilihaele Stream near Huelo, Maui, 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
HOOLAWANUI STREAM NR HUELO, MAUI, 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
Puohokamoa Str ab Spreckels Ditch, Maui, 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
Haipuaena Stream abv Spreckels Ditch, Maui, 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
Honomanu Stream near Keanae, Maui, 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
Lowrie Ditch at Honopou Gulch near Huelo, Maui, 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
Haiku Ditch at Honopou Gulch near Kailua, Maui, 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
Koolau Ditch near Keanae, Maui, 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
New Hamakua Ditch at Honopou near Huelo, Maui, 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
KOOLAU DITCH AT NAHIKU WEIR NR NAHIKU, MAUI, 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
Manuel Luis Ditch at Puohokamoa Stream, Maui, 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
Wailoa Ditch at Honopou near Huelo, Maui, 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
SPRECKELS DITCH AT HAIPUAENA WEIR NR HUELO, MAUI	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
HONOKOWAI DITCH NEAR LAHAINA, MAUI, 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
PALIKEA STREAM BL DIV DAM NR KIPAHULU, MAUI, 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
M B PUOHOKAMOA STR AT HAIKU-UKA BDRY NR KAILIILI	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
Kauaula Stream US of ditch diversion, Maui, 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
Ukumehame Gulch nr Olowalu, Maui, 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	19	yes, 3 or more
Years spanned	117	yes, 20 or more
Values held	4,014	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-16587000.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), Maui gauge records, accessed 2026-10-05, hydrionis.com/waters/united-states-maui/

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 Maui 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 confidence2025-01-30

Source: USGS — National Water Information System, USGS site 16587000, 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.