The monitoring network within this area

Hydrionis holds 369,923 values from 26 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.

26
Gauges
369,923
Values held
1911–2026
Record spans
Gauges within the Iijoki drainage basin
26 monitoring points, positioned as the publisher records them.
Gauges within the Iijoki drainage basinPuossunjärvi - luusua, Iso-Kero - luusua, Irnijärvi, pato, Jokijärvi - luusua, Kuoliojoki, Koitijärvi - luusua, Kuoliojoki, Näljänkäjärvi - luusua, Irnijärvi, pato, Kostonjärvi, pato, Väätäjänsuvanto, Suolijärvi - luusua, Kurenalus, Kurenalus, Kurenalus, Livojoki, Hanhikoski, Jaurakkajärvi - luusua, Kipinä, Livojoki, Hanhikoski, Haapakoski, Pahkakoski, Kierikki, Maalismaa, Siuruanjoki, Leuvankoski, Merikoski, RaasakkaPuossunjärvi - luusuaIso-Kero - luusuaIrnijärvi, patoJokijärvi - luusuaKuoliojokiKoitijärvi - luusuaKuoliojokiNäljänkäjärvi - luusuaIrnijärvi, patoKostonjärvi, patoVäätäjänsuvantoSuolijärvi - luusuaKurenalusKurenalusKurenalusLivojoki, HanhikoskiJaurakkajärvi - luusuaKipinäLivojoki, HanhikoskiHaapakoskiPahkakoskiKierikkiMaalismaaSiuruanjoki, LeuvankoskiMerikoskiRaasakka

How low, how high and how variable this gauge runs

A hydrograph says what happened; these say how often. Read off Siuruanjoki, Leuvankoski's whole daily record between 1959 and 2026, they describe the shape of the record rather than any day in it — and they belong to this gauge and its reach, not to this drainage area.

3.500 m³/s
Q95 low flow
13.900 m³/s
Q50 median flow
70.320 m³/s
Q10 high flow
Largest day of each water year at Siuruanjoki, Leuvankoski
The highest daily mean discharge in each October-to-September water year, 1959–2025.
Largest day of each water year at Siuruanjoki, LeuvankoskiLargest day of each water year at Siuruanjoki, Leuvankoski: Siuruanjoki, Leuvankoski in m³/s, from 1959 to 2025.0200400600800m³/s19591968197719861995200420132022Siuruanjoki, Leuvankoski 1959: 228 m³/sSiuruanjoki, Leuvankoski 1960: 443 m³/sSiuruanjoki, Leuvankoski 1961: 324 m³/sSiuruanjoki, Leuvankoski 1962: 236 m³/sSiuruanjoki, Leuvankoski 1963: 321 m³/sSiuruanjoki, Leuvankoski 1964: 397 m³/sSiuruanjoki, Leuvankoski 1965: 184 m³/sSiuruanjoki, Leuvankoski 1966: 398 m³/sSiuruanjoki, Leuvankoski 1967: 291 m³/sSiuruanjoki, Leuvankoski 1968: 512 m³/sSiuruanjoki, Leuvankoski 1969: 332 m³/sSiuruanjoki, Leuvankoski 1970: 665 m³/sSiuruanjoki, Leuvankoski 1971: 157 m³/sSiuruanjoki, Leuvankoski 1972: 426 m³/sSiuruanjoki, Leuvankoski 1973: 433 m³/sSiuruanjoki, Leuvankoski 1974: 504 m³/sSiuruanjoki, Leuvankoski 1975: 160 m³/sSiuruanjoki, Leuvankoski 1976: 672 m³/sSiuruanjoki, Leuvankoski 1977: 262 m³/sSiuruanjoki, Leuvankoski 1978: 381 m³/sSiuruanjoki, Leuvankoski 1979: 182 m³/sSiuruanjoki, Leuvankoski 1980: 556 m³/sSiuruanjoki, Leuvankoski 1981: 598 m³/sSiuruanjoki, Leuvankoski 1982: 437 m³/sSiuruanjoki, Leuvankoski 1983: 412 m³/sSiuruanjoki, Leuvankoski 1984: 520 m³/sSiuruanjoki, Leuvankoski 1985: 280 m³/sSiuruanjoki, Leuvankoski 1986: 483 m³/sSiuruanjoki, Leuvankoski 1987: 343 m³/sSiuruanjoki, Leuvankoski 1988: 690 m³/sSiuruanjoki, Leuvankoski 1989: 254 m³/sSiuruanjoki, Leuvankoski 1990: 176 m³/sSiuruanjoki, Leuvankoski 1991: 584 m³/sSiuruanjoki, Leuvankoski 1992: 694 m³/sSiuruanjoki, Leuvankoski 1993: 516 m³/sSiuruanjoki, Leuvankoski 1994: 289 m³/sSiuruanjoki, Leuvankoski 1995: 213 m³/sSiuruanjoki, Leuvankoski 1996: 508 m³/sSiuruanjoki, Leuvankoski 1997: 348 m³/sSiuruanjoki, Leuvankoski 1998: 309 m³/sSiuruanjoki, Leuvankoski 1999: 455 m³/sSiuruanjoki, Leuvankoski 2000: 438 m³/sSiuruanjoki, Leuvankoski 2001: 345 m³/sSiuruanjoki, Leuvankoski 2002: 256 m³/sSiuruanjoki, Leuvankoski 2003: 141 m³/sSiuruanjoki, Leuvankoski 2004: 268 m³/sSiuruanjoki, Leuvankoski 2005: 363 m³/sSiuruanjoki, Leuvankoski 2006: 197 m³/sSiuruanjoki, Leuvankoski 2007: 494 m³/sSiuruanjoki, Leuvankoski 2008: 283 m³/sSiuruanjoki, Leuvankoski 2009: 201 m³/sSiuruanjoki, Leuvankoski 2010: 147 m³/sSiuruanjoki, Leuvankoski 2011: 478 m³/sSiuruanjoki, Leuvankoski 2012: 381 m³/sSiuruanjoki, Leuvankoski 2013: 235 m³/sSiuruanjoki, Leuvankoski 2014: 435 m³/sSiuruanjoki, Leuvankoski 2015: 301 m³/sSiuruanjoki, Leuvankoski 2016: 441 m³/sSiuruanjoki, Leuvankoski 2017: 345 m³/sSiuruanjoki, Leuvankoski 2018: 360 m³/sSiuruanjoki, Leuvankoski 2019: 306 m³/sSiuruanjoki, Leuvankoski 2020: 264 m³/sSiuruanjoki, Leuvankoski 2021: 327 m³/sSiuruanjoki, Leuvankoski 2022: 280 m³/sSiuruanjoki, Leuvankoski 2023: 348 m³/sSiuruanjoki, Leuvankoski 2024: 188 m³/sSiuruanjoki, Leuvankoski 2025: 335 m³/s

These are the largest daily means, not flood peaks. A peak lasting hours is averaged across a whole day here, so the true instantaneous maximum on the same day was higher — sometimes far higher on a fast-responding catchment. Flood frequency work needs a publisher's own instantaneous series; Hydrionis holds one for 2,236 American gauges and not for this one, so the two are never drawn together. A water year the gauge did not substantially cover produces no value at all rather than a low one.

View the data behind this chart
Underlying data
PeriodSiuruanjoki, Leuvankoski (m³/s)
1959228
1960443
1961324
1962236
1963321
1964397
1965184
1966398
1967291
1968512
1969332
1970665
1971157
1972426
1973433
1974504
1975160
1976672
1977262
1978381
1979182
1980556
1981598
1982437
1983412
1984520
1985280
1986483
1987343
1988690
1989254
1990176
1991584
1992694
1993516
1994289
1995213
1996508
1997348
1998309
1999455
2000438
2001345
2002256
2003141
2004268
2005363
2006197
2007494
2008283
2009201
2010147
2011478
2012381
2013235
2014435
2015301
2016441
2017345
2018360
2019306
2020264
2021327
2022280
2023348
2024188
2025335

The longest record here

Mean river flow at Siuruanjoki, Leuvankoski
Annual means of the daily record, 1960–2025. One gauge, not this drainage area.
Mean river flow at Siuruanjoki, LeuvankoskiMean river flow at Siuruanjoki, Leuvankoski: Siuruanjoki, Leuvankoski in m³/s, from 1960 to 2025.204060m³/s19601969197819871996200520142023Siuruanjoki, Leuvankoski 1960: 18.7 m³/sSiuruanjoki, Leuvankoski 1961: 40.3 m³/sSiuruanjoki, Leuvankoski 1962: 38.1 m³/sSiuruanjoki, Leuvankoski 1963: 21.6 m³/sSiuruanjoki, Leuvankoski 1964: 33.0 m³/sSiuruanjoki, Leuvankoski 1965: 41.0 m³/sSiuruanjoki, Leuvankoski 1966: 33.6 m³/sSiuruanjoki, Leuvankoski 1967: 42.5 m³/sSiuruanjoki, Leuvankoski 1968: 22.5 m³/sSiuruanjoki, Leuvankoski 1969: 21.8 m³/sSiuruanjoki, Leuvankoski 1970: 24.5 m³/sSiuruanjoki, Leuvankoski 1971: 32.5 m³/sSiuruanjoki, Leuvankoski 1972: 19.8 m³/sSiuruanjoki, Leuvankoski 1973: 29.4 m³/sSiuruanjoki, Leuvankoski 1974: 35.9 m³/sSiuruanjoki, Leuvankoski 1975: 30.3 m³/sSiuruanjoki, Leuvankoski 1976: 18.3 m³/sSiuruanjoki, Leuvankoski 1977: 39.0 m³/sSiuruanjoki, Leuvankoski 1978: 17.1 m³/sSiuruanjoki, Leuvankoski 1979: 29.8 m³/sSiuruanjoki, Leuvankoski 1980: 17.3 m³/sSiuruanjoki, Leuvankoski 1981: 40.5 m³/sSiuruanjoki, Leuvankoski 1982: 34.5 m³/sSiuruanjoki, Leuvankoski 1983: 35.3 m³/sSiuruanjoki, Leuvankoski 1984: 34.4 m³/sSiuruanjoki, Leuvankoski 1985: 36.4 m³/sSiuruanjoki, Leuvankoski 1986: 30.8 m³/sSiuruanjoki, Leuvankoski 1987: 31.2 m³/sSiuruanjoki, Leuvankoski 1988: 24.0 m³/sSiuruanjoki, Leuvankoski 1989: 47.4 m³/sSiuruanjoki, Leuvankoski 1990: 23.3 m³/sSiuruanjoki, Leuvankoski 1991: 33.7 m³/sSiuruanjoki, Leuvankoski 1992: 42.9 m³/sSiuruanjoki, Leuvankoski 1993: 33.0 m³/sSiuruanjoki, Leuvankoski 1994: 28.7 m³/sSiuruanjoki, Leuvankoski 1995: 28.3 m³/sSiuruanjoki, Leuvankoski 1996: 20.1 m³/sSiuruanjoki, Leuvankoski 1997: 21.8 m³/sSiuruanjoki, Leuvankoski 1998: 41.7 m³/sSiuruanjoki, Leuvankoski 1999: 25.7 m³/sSiuruanjoki, Leuvankoski 2000: 43.4 m³/sSiuruanjoki, Leuvankoski 2001: 22.8 m³/sSiuruanjoki, Leuvankoski 2002: 18.2 m³/sSiuruanjoki, Leuvankoski 2003: 25.0 m³/sSiuruanjoki, Leuvankoski 2004: 29.6 m³/sSiuruanjoki, Leuvankoski 2005: 37.3 m³/sSiuruanjoki, Leuvankoski 2006: 24.7 m³/sSiuruanjoki, Leuvankoski 2007: 32.3 m³/sSiuruanjoki, Leuvankoski 2008: 40.0 m³/sSiuruanjoki, Leuvankoski 2009: 27.3 m³/sSiuruanjoki, Leuvankoski 2010: 27.1 m³/sSiuruanjoki, Leuvankoski 2011: 27.3 m³/sSiuruanjoki, Leuvankoski 2012: 49.5 m³/sSiuruanjoki, Leuvankoski 2013: 30.8 m³/sSiuruanjoki, Leuvankoski 2014: 34.5 m³/sSiuruanjoki, Leuvankoski 2015: 54.7 m³/sSiuruanjoki, Leuvankoski 2016: 34.4 m³/sSiuruanjoki, Leuvankoski 2017: 29.6 m³/sSiuruanjoki, Leuvankoski 2018: 25.4 m³/sSiuruanjoki, Leuvankoski 2019: 30.9 m³/sSiuruanjoki, Leuvankoski 2020: 50.6 m³/sSiuruanjoki, Leuvankoski 2021: 37.6 m³/sSiuruanjoki, Leuvankoski 2022: 30.0 m³/sSiuruanjoki, Leuvankoski 2023: 34.5 m³/sSiuruanjoki, Leuvankoski 2024: 33.4 m³/sSiuruanjoki, Leuvankoski 2025: 35.1 m³/s

Annual means computed by Hydrionis from the published daily record, drawn only for years with at least 300 days held. They summarise this gauge's own record and say nothing about any other watercourse in this area.

View the data behind this chart
Underlying data
PeriodSiuruanjoki, Leuvankoski (m³/s)
196018.7
196140.3
196238.1
196321.6
196433.0
196541.0
196633.6
196742.5
196822.5
196921.8
197024.5
197132.5
197219.8
197329.4
197435.9
197530.3
197618.3
197739.0
197817.1
197929.8
198017.3
198140.5
198234.5
198335.3
198434.4
198536.4
198630.8
198731.2
198824.0
198947.4
199023.3
199133.7
199242.9
199333.0
199428.7
199528.3
199620.1
199721.8
199841.7
199925.7
200043.4
200122.8
200218.2
200325.0
200429.6
200537.3
200624.7
200732.3
200840.0
200927.3
201027.1
201127.3
201249.5
201330.8
201434.5
201554.7
201634.4
201729.6
201825.4
201930.9
202050.6
202137.6
202230.0
202334.5
202433.4
202535.1

Every gauge Hydrionis holds within this area

Gauges within the Iijoki and what each holds
GaugeMeasuresValuesRecord
Siuruanjoki, Leuvankoskimean river flow24,4721959–2026
Jaurakkajärvi - luusuamean river flow24,3191960–2026
Suolijärvi - luusuamean river flow23,9511961–2026
Väätäjänsuvantomean river flow23,8031956–2026
Haapakoskimean river flow23,0671963–2026
Kostonjärvi, patomean river flow22,5351965–2026
Merikoskimean river flow22,2801911–1971
Irnijärvi, patomean river flow22,0341966–2026
Pahkakoskimean river flow21,8381961–2026
Raasakkamean river flow20,3611971–2026
Kierikkimean river flow20,2691966–2026
Maalismaamean river flow19,5391968–2026
Livojoki, Hanhikoskimean river flow19,2651974–2026
Kurenalusmean river flow14,8831986–2026
Kipinämean river flow14,6101956–1995
Puossunjärvi - luusuamean river flow11,4731960–1994
Kuoliojokimean river flow7,6701970–1990
Kurenalusmean river flow6,9011956–1976
Koitijärvi - luusuamean river flow6,8441961–1991
Näljänkäjärvi - luusuamean river flow6,2091978–1994
Kurenalusmean river flow3,2871977–1985
Jokijärvi - luusuamean river flow2,8111961–1968
Irnijärvi, patomean river flow2,1611959–1965
Livojoki, Hanhikoskimean river flow2,0551960–1965
Kuoliojokimean river flow1,8261965–1969
Iso-Kero - luusuamean river flow1,4601961–1964

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 — 61. 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
GaugeEvidenceEstablished
Siuruanjoki, LeuvankoskiStated by the publisher on the record this gauge’s observations came from.With the observations
Jaurakkajärvi - luusuaStated by the publisher on the record this gauge’s observations came from.With the observations
Suolijärvi - luusuaStated by the publisher on the record this gauge’s observations came from.With the observations
VäätäjänsuvantoStated by the publisher on the record this gauge’s observations came from.With the observations
HaapakoskiStated by the publisher on the record this gauge’s observations came from.With the observations
Kostonjärvi, patoStated by the publisher on the record this gauge’s observations came from.With the observations
MerikoskiStated by the publisher on the record this gauge’s observations came from.With the observations
Irnijärvi, patoStated by the publisher on the record this gauge’s observations came from.With the observations
PahkakoskiStated by the publisher on the record this gauge’s observations came from.With the observations
RaasakkaStated by the publisher on the record this gauge’s observations came from.With the observations
KierikkiStated by the publisher on the record this gauge’s observations came from.With the observations
MaalismaaStated by the publisher on the record this gauge’s observations came from.With the observations
Livojoki, HanhikoskiStated by the publisher on the record this gauge’s observations came from.With the observations
KurenalusStated by the publisher on the record this gauge’s observations came from.With the observations
KipinäStated by the publisher on the record this gauge’s observations came from.With the observations
Puossunjärvi - luusuaStated by the publisher on the record this gauge’s observations came from.With the observations
KuoliojokiStated by the publisher on the record this gauge’s observations came from.With the observations
KurenalusStated by the publisher on the record this gauge’s observations came from.With the observations
Koitijärvi - luusuaStated by the publisher on the record this gauge’s observations came from.With the observations
Näljänkäjärvi - luusuaStated by the publisher on the record this gauge’s observations came from.With the observations
KurenalusStated by the publisher on the record this gauge’s observations came from.With the observations
Jokijärvi - luusuaStated by the publisher on the record this gauge’s observations came from.With the observations
Irnijärvi, patoStated by the publisher on the record this gauge’s observations came from.With the observations
Livojoki, HanhikoskiStated by the publisher on the record this gauge’s observations came from.With the observations
KuoliojokiStated by the publisher on the record this gauge’s observations came from.With the observations
Iso-Kero - luusuaStated by the publisher on the record this gauge’s observations came from.With the observations

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
SignalHeldCounts
Gauges holding a real record26yes, 3 or more
Years spanned116yes, 20 or more
Values held369,923yes, 1000 or more
Distinct measurements1no
Publishers measuring it1no
Official identifiers1recorded, not counted

Use this data

Use this data

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

Attribution you are required to give

These are conditions of the licences the underlying data is published under. They are obligations to the publishers, not to Hydrionis, and they apply to you directly whether or not you mention Hydrionis at all.

Contains data from the Finnish Environment Institute (Syke), licensed under CC BY 4.0.

Suggested citation for Hydrionis

Hydrionis (2026), Iijoki gauge records, accessed 2026-10-05, hydrionis.com/waters/finland-iijoki/

Cite Hydrionis where you rely on the compilation, the normalisation, the eligibility judgements or a chart. Where you use an unmodified published value, the publisher’s attribution is the one that is required; crediting Hydrionis as well is welcome and is not something Hydrionis can require of you.

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 Iijoki 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.

Where these figures come from

MeasuredHigh confidence2026-09-30

Source: Syke — Hydrologiarajapinta — Finnish national hydrological archive, 6101600. Licence: Open — attribution required (attribution required).

Method: Daily discharge exactly as the Finnish Environment Institute publishes it. Syke computes the daily value from its own measurement and rating curves; Hydrionis does not recompute it, because a mean derived from whatever sub-daily data happens to be exposed would be a different statistic under the same name. Values Syke flags as possibly erroneous are not stored.

21 of these values (under 1%) are interpolated by Syke rather than measured, and are marked as such in its own archive. Station in the Iijoki main drainage basin, Leuankosken a sub-basin. Discharge is a property of this gauge and this reach, not of the river as a whole.

Retrieved 1 October 2026.