The monitoring network within this area

Hydrionis holds 229,153 values from 19 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.

19
Gauges
229,153
Values held
1931–2026
Record spans
Gauges within the Lapuanjoki drainage basin
19 monitoring points, positioned as the publisher records them.
Gauges within the Lapuanjoki drainage basinTöysänjoki, Nurmonjoki, Hirvikoski + Nurmonjoki, Tampparinkoski, Keppo, Pappilankari, Uusikaarlepyy, Keppo, Kätkänjärvi, Kuotesjärvi, Jääskänjärvi, Kuorasjärvi, Varpulan tekojärvi, Vähä-Allasjärvi, Iso-Allasjärvi, Mäkelänkoski, kokonaisvirtaama, Hourunkoski, kokonaisvirtaama, Saukkojärvi, Jääskänjärven kalatieTöysänjokiNurmonjokiHirvikoski + NurmonjokiTampparinkoskiKeppoPappilankariUusikaarlepyyKeppoKätkänjärviKuotesjärviJääskänjärviKuorasjärviVarpulan tekojärviVähä-AllasjärviIso-AllasjärviMäkelänkoski, kokonaisvirtaamaHourunkoski, kokonaisvirtaamaSaukkojärviJääskänjärven kalatie

How low, how high and how variable this gauge runs

A hydrograph says what happened; these say how often. Read off Keppo's whole daily record between 1957 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.

3.210 m³/s
Q95 low flow
19.000 m³/s
Q50 median flow
85.000 m³/s
Q10 high flow
Largest day of each water year at Keppo
The highest daily mean discharge in each October-to-September water year, 1957–2025.
Largest day of each water year at KeppoLargest day of each water year at Keppo: Keppo in m³/s, from 1957 to 2025.100200300m³/s19571966197519841993200220112020Keppo 1957: 223 m³/sKeppo 1958: 169 m³/sKeppo 1959: 96.0 m³/sKeppo 1960: 150 m³/sKeppo 1961: 282 m³/sKeppo 1962: 153 m³/sKeppo 1963: 111 m³/sKeppo 1964: 287 m³/sKeppo 1965: 298 m³/sKeppo 1966: 223 m³/sKeppo 1967: 193 m³/sKeppo 1968: 184 m³/sKeppo 1969: 190 m³/sKeppo 1970: 148 m³/sKeppo 1971: 247 m³/sKeppo 1972: 128 m³/sKeppo 1973: 179 m³/sKeppo 1974: 153 m³/sKeppo 1975: 177 m³/sKeppo 1976: 296 m³/sKeppo 1977: 83.0 m³/sKeppo 1978: 147 m³/sKeppo 1979: 160 m³/sKeppo 1980: 218 m³/sKeppo 1981: 312 m³/sKeppo 1982: 251 m³/sKeppo 1983: 320 m³/sKeppo 1984: 303 m³/sKeppo 1985: 191 m³/sKeppo 1986: 194 m³/sKeppo 1987: 289 m³/sKeppo 1988: 167 m³/sKeppo 1989: 145 m³/sKeppo 1990: 227 m³/sKeppo 1991: 199 m³/sKeppo 1992: 229 m³/sKeppo 1993: 227 m³/sKeppo 1994: 171 m³/sKeppo 1995: 135 m³/sKeppo 1996: 152 m³/sKeppo 1997: 246 m³/sKeppo 1998: 232 m³/sKeppo 1999: 277 m³/sKeppo 2000: 246 m³/sKeppo 2001: 165 m³/sKeppo 2002: 109 m³/sKeppo 2003: 226 m³/sKeppo 2004: 107 m³/sKeppo 2005: 263 m³/sKeppo 2006: 128 m³/sKeppo 2007: 147 m³/sKeppo 2008: 202 m³/sKeppo 2009: 265 m³/sKeppo 2010: 251 m³/sKeppo 2011: 196 m³/sKeppo 2012: 273 m³/sKeppo 2013: 186 m³/sKeppo 2014: 185 m³/sKeppo 2015: 186 m³/sKeppo 2016: 137 m³/sKeppo 2017: 289 m³/sKeppo 2018: 92.0 m³/sKeppo 2019: 148 m³/sKeppo 2020: 251 m³/sKeppo 2021: 201 m³/sKeppo 2022: 235 m³/sKeppo 2023: 266 m³/sKeppo 2024: 175 m³/sKeppo 2025: 165 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
PeriodKeppo (m³/s)
1957223
1958169
195996.0
1960150
1961282
1962153
1963111
1964287
1965298
1966223
1967193
1968184
1969190
1970148
1971247
1972128
1973179
1974153
1975177
1976296
197783.0
1978147
1979160
1980218
1981312
1982251
1983320
1984303
1985191
1986194
1987289
1988167
1989145
1990227
1991199
1992229
1993227
1994171
1995135
1996152
1997246
1998232
1999277
2000246
2001165
2002109
2003226
2004107
2005263
2006128
2007147
2008202
2009265
2010251
2011196
2012273
2013186
2014185
2015186
2016137
2017289
201892.0
2019148
2020251
2021201
2022235
2023266
2024175
2025165

The longest record here

Mean river flow at Keppo
Annual means of the daily record, 1957–2025. One gauge, not this drainage area.
Mean river flow at KeppoMean river flow at Keppo: Keppo in m³/s, from 1957 to 2025.204060m³/s19571966197519841993200220112020Keppo 1957: 44.5 m³/sKeppo 1958: 29.7 m³/sKeppo 1959: 23.2 m³/sKeppo 1960: 23.0 m³/sKeppo 1961: 38.5 m³/sKeppo 1962: 34.4 m³/sKeppo 1963: 26.3 m³/sKeppo 1964: 20.7 m³/sKeppo 1965: 32.8 m³/sKeppo 1966: 32.6 m³/sKeppo 1967: 49.4 m³/sKeppo 1968: 28.2 m³/sKeppo 1969: 21.6 m³/sKeppo 1970: 20.6 m³/sKeppo 1971: 35.4 m³/sKeppo 1972: 40.8 m³/sKeppo 1973: 18.9 m³/sKeppo 1974: 60.9 m³/sKeppo 1975: 24.2 m³/sKeppo 1976: 18.7 m³/sKeppo 1977: 39.6 m³/sKeppo 1978: 17.6 m³/sKeppo 1979: 31.8 m³/sKeppo 1980: 27.1 m³/sKeppo 1981: 58.1 m³/sKeppo 1982: 44.8 m³/sKeppo 1983: 31.7 m³/sKeppo 1984: 42.8 m³/sKeppo 1985: 27.1 m³/sKeppo 1986: 38.4 m³/sKeppo 1987: 39.2 m³/sKeppo 1988: 49.7 m³/sKeppo 1989: 34.8 m³/sKeppo 1990: 33.4 m³/sKeppo 1991: 37.1 m³/sKeppo 1992: 53.3 m³/sKeppo 1993: 30.5 m³/sKeppo 1994: 30.0 m³/sKeppo 1995: 27.2 m³/sKeppo 1996: 27.1 m³/sKeppo 1997: 23.0 m³/sKeppo 1998: 42.1 m³/sKeppo 1999: 29.6 m³/sKeppo 2000: 43.3 m³/sKeppo 2001: 38.8 m³/sKeppo 2002: 26.5 m³/sKeppo 2003: 23.1 m³/sKeppo 2004: 29.9 m³/sKeppo 2005: 32.8 m³/sKeppo 2006: 31.5 m³/sKeppo 2007: 32.8 m³/sKeppo 2008: 46.7 m³/sKeppo 2009: 19.2 m³/sKeppo 2010: 26.9 m³/sKeppo 2011: 42.4 m³/sKeppo 2012: 48.6 m³/sKeppo 2013: 34.5 m³/sKeppo 2014: 26.4 m³/sKeppo 2015: 45.8 m³/sKeppo 2016: 37.2 m³/sKeppo 2017: 34.6 m³/sKeppo 2018: 24.8 m³/sKeppo 2019: 27.1 m³/sKeppo 2020: 42.1 m³/sKeppo 2021: 33.2 m³/sKeppo 2022: 34.7 m³/sKeppo 2023: 50.5 m³/sKeppo 2024: 40.8 m³/sKeppo 2025: 34.7 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
PeriodKeppo (m³/s)
195744.5
195829.7
195923.2
196023.0
196138.5
196234.4
196326.3
196420.7
196532.8
196632.6
196749.4
196828.2
196921.6
197020.6
197135.4
197240.8
197318.9
197460.9
197524.2
197618.7
197739.6
197817.6
197931.8
198027.1
198158.1
198244.8
198331.7
198442.8
198527.1
198638.4
198739.2
198849.7
198934.8
199033.4
199137.1
199253.3
199330.5
199430.0
199527.2
199627.1
199723.0
199842.1
199929.6
200043.3
200138.8
200226.5
200323.1
200429.9
200532.8
200631.5
200732.8
200846.7
200919.2
201026.9
201142.4
201248.6
201334.5
201426.4
201545.8
201637.2
201734.6
201824.8
201927.1
202042.1
202133.2
202234.7
202350.5
202440.8
202534.7

Every gauge Hydrionis holds within this area

Gauges within the Lapuanjoki and what each holds
GaugeMeasuresValuesRecord
Keppomean river flow25,4751957–2026
Pappilankarimean river flow22,9191931–1993
Töysänjokimean river flow16,9541980–2026
Tampparinkoskimean river flow16,9241980–2026
Uusikaarlepyymean river flow15,8701970–2026
Nurmonjokimean river flow15,0351933–1975
Kätkänjärvimean river flow12,2131970–2026
Varpulan tekojärvimean river flow10,9401970–2026
Kuorasjärvimean river flow10,1791970–2026
Kuotesjärvimean river flow10,1361970–2026
Jääskänjärvimean river flow10,0331970–2026
Hirvikoski + Nurmonjokimean river flow9,8831999–2026
Vähä-Allasjärvimean river flow9,8691999–2026
Iso-Allasjärvimean river flow9,8681999–2026
Saukkojärvimean river flow9,5131999–2026
Keppomean river flow9,4971931–1956
Hourunkoski, kokonaisvirtaamamean river flow7,4702005–2026
Mäkelänkoski, kokonaisvirtaamamean river flow4,9382013–2026
Jääskänjärven kalatiemean river flow1,4372022–2026

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 — 44. 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
KeppoStated by the publisher on the record this gauge’s observations came from.With the observations
PappilankariStated by the publisher on the record this gauge’s observations came from.With the observations
TöysänjokiStated by the publisher on the record this gauge’s observations came from.With the observations
TampparinkoskiStated by the publisher on the record this gauge’s observations came from.With the observations
UusikaarlepyyStated by the publisher on the record this gauge’s observations came from.With the observations
NurmonjokiStated by the publisher on the record this gauge’s observations came from.With the observations
KätkänjärviStated by the publisher on the record this gauge’s observations came from.With the observations
Varpulan tekojärviStated by the publisher on the record this gauge’s observations came from.With the observations
KuorasjärviStated by the publisher on the record this gauge’s observations came from.With the observations
KuotesjärviStated by the publisher on the record this gauge’s observations came from.With the observations
JääskänjärviStated by the publisher on the record this gauge’s observations came from.With the observations
Hirvikoski + NurmonjokiStated by the publisher on the record this gauge’s observations came from.With the observations
Vähä-AllasjärviStated by the publisher on the record this gauge’s observations came from.With the observations
Iso-AllasjärviStated by the publisher on the record this gauge’s observations came from.With the observations
SaukkojärviStated by the publisher on the record this gauge’s observations came from.With the observations
KeppoStated by the publisher on the record this gauge’s observations came from.With the observations
Hourunkoski, kokonaisvirtaamaStated by the publisher on the record this gauge’s observations came from.With the observations
Mäkelänkoski, kokonaisvirtaamaStated by the publisher on the record this gauge’s observations came from.With the observations
Jääskänjärven kalatieStated 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 record19yes, 3 or more
Years spanned96yes, 20 or more
Values held229,153yes, 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), Lapuanjoki gauge records, accessed 2026-10-05, hydrionis.com/waters/finland-lapuanjoki/

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 Lapuanjoki 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, 4400610. 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.

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

Retrieved 1 October 2026.