The monitoring network within this area

Hydrionis holds 1,888 values from 4 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.

4

Gauges

1,888

Values held

1905–2026

Record spans

Gauges within the North Santiam huc8 subbasin

4 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 NORTH SANTIAM RIVER AT MEHAMA, OR

The highest instantaneous discharge the publisher recorded in each year — a flood peak as measured, not a daily average of one. 1906–2025.

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	NORTH SANTIAM RIVER AT MEHAMA, OR (m³/s)
1906	586
1907	1,441
1910	756
1912	1,393
1913	968
1921	1,781
1923	1,781
1925	892
1926	963
1927	1,359
1929	391
1931	1,529
1932	1,331
1933	745
1934	966
1936	866
1937	852
1938	895
1940	564
1941	753
1942	1,606
1943	515
1945	946
1946	1,484
1948	1,705
1949	1,031
1950	1,107
1951	660
1953	674
1954	498
1956	716
1957	501
1958	527
1960	425
1961	487
1962	742
1963	583
1964	1,654
1966	453
1967	493
1968	592
1970	597
1971	597
1972	1,226
1974	637
1975	626
1977	134
1978	609
1980	513
1981	549
1983	564
1984	481
1986	835
1987	498
1989	612
1990	705
1991	459
1993	535
1994	351
1996	1,523
1997	510
1998	716
1999	1,005
2001	244
2002	646
2003	464
2004	343
2006	549
2008	425
2009	728
2010	665
2011	1,031
2012	801
2014	595
2015	634
2017	586
2019	504
2020	493
2022	668
2023	663
2025	544

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	1906–2025
Completeness	67.5% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	32 separate periods inside 1906–2025 hold no value. The longest runs from 1914 to 1920 — 7 years with no reading. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1906 and is not continuous from it: 120 years separate the first value from the last, and 68% 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 NORTH SANTIAM RIVER AT MEHAMA, OR, as a depth

The year's flow spread over the land draining to this gauge, in millimetres — the same unit rainfall is measured in. 1906–2024.

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	NORTH SANTIAM RIVER AT MEHAMA, OR (mm)
1906	2,061
1911	1,505
1912	2,402
1913	2,052
1922	1,564
1923	1,866
1924	1,510
1925	1,797
1926	1,459
1927	2,178
1928	1,566
1929	1,332
1930	1,094
1931	1,277
1932	2,024
1933	2,201
1934	1,564
1935	1,268
1936	1,484
1937	1,996
1938	1,697
1939	1,277
1940	1,366
1941	1,256
1942	1,690
1943	1,790
1944	948
1945	1,926
1946	2,070
1947	1,656
1948	1,928
1949	1,827
1950	2,616
1951	1,991
1952	1,442
1953	2,397
1954	1,761
1955	2,283
1956	2,239
1957	1,568
1958	2,010
1959	1,699
1960	1,905
1961	2,017
1962	1,827
1963	1,545
1964	1,999
1965	1,575
1966	1,658
1967	1,493
1968	1,949
1969	1,685
1970	1,845
1971	2,323
1972	2,389
1973	1,736
1974	2,287
1975	2,193
1976	1,540
1977	1,743
1978	1,397
1979	1,527
1980	1,590
1981	1,745
1982	2,129
1983	2,158
1984	2,173
1985	1,471
1986	1,793
1987	1,190
1988	1,644
1989	1,464
1990	1,727
1991	1,581
1992	1,133
1993	1,590
1994	1,487
1995	2,258
1996	2,663
1997	2,216
1998	1,901
1999	2,338
2000	1,540
2001	1,305
2002	1,592
2003	1,823
2004	1,664
2005	1,298
2006	2,240
2007	1,730
2008	1,999
2009	1,895
2010	2,016
2011	1,908
2012	2,606
2013	1,603
2014	2,278
2015	1,408
2016	1,921
2017	2,451
2018	1,491
2019	1,449
2020	1,794
2021	1,724
2022	2,071
2023	1,639
2024	1,899

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	1906–2024
Completeness	89.9% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps	2 separate periods inside 1906–2024 hold no value. The longest runs from 1914 to 1921 — 8 years with no reading. They are drawn as breaks in the line and are never interpolated across.
Continuity	The record begins in 1906 and is not continuous from it: 119 years separate the first value from the last, and 90% 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

1 automated snow station sits inside this drainage area, weighing the snowpack rather than measuring how deep it is.

862

Fullest snowpack recorded at Marion Forks, in 2008 (mm of water)

6

Thinnest, in 2015 (mm of water)

March

Month the pack is usually at its fullest

May

Month the pack has gone by, in half of years

Peak snowpack at Marion Forks

Water years 1981–2026. 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	Marion Forks (mm)
1981	34.0
1982	488
1983	109
1984	152
1985	574
1986	234
1987	84.0
1988	263
1989	433
1990	421
1991	110
1992	25.0
1993	412
1994	92.0
1995	272
1996	84.0
1997	349
1998	88.0
1999	640
2000	341
2001	132
2002	629
2003	47.0
2004	309
2005	59.0
2006	216
2007	154
2008	862
2009	396
2010	67.0
2011	196
2012	396
2013	299
2014	98.0
2015	6.00
2016	174
2017	452
2018	172
2019	324
2020	222
2021	198
2022	285
2023	410
2024	208
2025	61.0
2026	21.0

Read against the river

Marion Forks and NO SANTIAM R BLW BOULDER CRK, NR DETROIT, OR both sit in this drainage area, and their records overlap by 44 years. That is the span the two have in common, not a count of years both actually hold — either record may have gaps inside it. The two are shown separately rather than on one axis: millimetres of stored water and cubic metres per second are not commensurable, and a difference between them would mean nothing.

Being in the same drainage area does not put the snowpack upstream of the gauge. A subbasin is an area, and snow on one tributary can join the river below a gauge on another — so a weak relationship here may say more about which tributary was measured than about the snow.

Every gauge Hydrionis holds within this area

Gauges within the North Santiam and what each holds
Gauge	Measures	Values	Record
NORTH SANTIAM RIVER AT MEHAMA, OR	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	362	1905–2026
NO SANTIAM R BLW BOULDER CRK, NR DETROIT, OR	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	333	1907–2026
NORTH SANTIAM RIVER AT NIAGARA, OR	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	324	1909–2026
SANTIAM RIVER AT JEFFERSON, OR	burned area within 50 km, catchment area, annual maximum river flow, mean river flow, mean river flow, water year	317	1907–2026

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 — 17090005. 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
NORTH SANTIAM RIVER AT MEHAMA, OR	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
NO SANTIAM R BLW BOULDER CRK, NR DETROIT, OR	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 SANTIAM RIVER AT NIAGARA, OR	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
SANTIAM RIVER AT JEFFERSON, OR	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	4	yes, 3 or more
Years spanned	122	yes, 20 or more
Values held	1,888	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-14183000.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), North Santiam gauge records, accessed 2026-10-05, hydrionis.com/waters/united-states-north-santiam/

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 North Santiam 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 14183000, 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.