The monitoring network within this area

Hydrionis holds 13,216 values from 2 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.

2
Gauges
13,216
Values held
1931–2026
Record spans
577 km²
Area
Gauges within the Olandsån drainage basin
2 monitoring points, positioned as the publisher records them.
Gauges within the Olandsån drainage basinFORS, FORS 2FORSFORS 2

How low, how high and how variable this gauge runs

A hydrograph says what happened; these say how often. Read off FORS's whole daily record between 1931 and 1959, 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.

0.450 m³/s
Q95 low flow
2.300 m³/s
Q50 median flow
10.800 m³/s
Q10 high flow
Largest day of each water year at FORS
The highest daily mean discharge in each October-to-September water year, 1931–1958.
Largest day of each water year at FORSLargest day of each water year at FORS: FORS in m³/s, from 1931 to 1958.02040m³/s1931193519391943194719511955FORS 1931: 37.0 m³/sFORS 1932: 10.1 m³/sFORS 1933: 9.40 m³/sFORS 1934: 28.0 m³/sFORS 1935: 18.3 m³/sFORS 1936: 44.0 m³/sFORS 1937: 15.8 m³/sFORS 1938: 12.4 m³/sFORS 1939: 23.0 m³/sFORS 1940: 19.6 m³/sFORS 1941: 18.3 m³/sFORS 1942: 18.2 m³/sFORS 1943: 23.0 m³/sFORS 1944: 27.0 m³/sFORS 1945: 15.5 m³/sFORS 1946: 18.9 m³/sFORS 1947: 20.0 m³/sFORS 1948: 7.00 m³/sFORS 1949: 19.4 m³/sFORS 1950: 33.0 m³/sFORS 1951: 21.0 m³/sFORS 1952: 17.6 m³/sFORS 1953: 28.0 m³/sFORS 1954: 17.2 m³/sFORS 1955: 34.0 m³/sFORS 1956: 23.0 m³/sFORS 1957: 30.0 m³/sFORS 1958: 37.0 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
PeriodFORS (m³/s)
193137.0
193210.1
19339.40
193428.0
193518.3
193644.0
193715.8
193812.4
193923.0
194019.6
194118.3
194218.2
194323.0
194427.0
194515.5
194618.9
194720.0
19487.00
194919.4
195033.0
195121.0
195217.6
195328.0
195417.2
195534.0
195623.0
195730.0
195837.0

The longest record here

Mean river flow at FORS
Annual means of the daily record, 1931–1958. One gauge, not this drainage area.
Mean river flow at FORSMean river flow at FORS: FORS in m³/s, from 1931 to 1958.246810m³/s1931193519391943194719511955FORS 1931: 4.61 m³/sFORS 1932: 4.25 m³/sFORS 1933: 2.02 m³/sFORS 1934: 4.59 m³/sFORS 1935: 4.52 m³/sFORS 1936: 6.04 m³/sFORS 1937: 4.32 m³/sFORS 1938: 3.42 m³/sFORS 1939: 3.30 m³/sFORS 1940: 3.44 m³/sFORS 1941: 3.07 m³/sFORS 1942: 3.08 m³/sFORS 1943: 4.62 m³/sFORS 1944: 6.00 m³/sFORS 1945: 4.92 m³/sFORS 1946: 4.51 m³/sFORS 1947: 2.36 m³/sFORS 1948: 2.82 m³/sFORS 1949: 4.22 m³/sFORS 1950: 4.25 m³/sFORS 1951: 3.26 m³/sFORS 1952: 3.66 m³/sFORS 1953: 3.26 m³/sFORS 1954: 6.23 m³/sFORS 1955: 4.43 m³/sFORS 1956: 4.51 m³/sFORS 1957: 9.17 m³/sFORS 1958: 5.38 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
PeriodFORS (m³/s)
19314.61
19324.25
19332.02
19344.59
19354.52
19366.04
19374.32
19383.42
19393.30
19403.44
19413.07
19423.08
19434.62
19446.00
19454.92
19464.51
19472.36
19482.82
19494.22
19504.25
19513.26
19523.66
19533.26
19546.23
19554.43
19564.51
19579.17
19585.38

Every gauge Hydrionis holds within this area

Gauges within the Olandsån and what each holds
GaugeMeasuresValuesRecord
FORSmean river flow10,5251931–1959
FORS 2mean river flow2,6912017–2026

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 — 56000. 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
FORSStated by the publisher on the record this gauge’s observations came from.With the observations
FORS 2Stated 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 2 of them, which makes it a profile, not indexed.

Information-gain signals held for this water body
SignalHeldCounts
Gauges holding a real record2no
Years spanned96yes, 20 or more
Values held13,216yes, 1000 or more
Distinct measurements1no
Publishers measuring it1no
Official identifiers2recorded, 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.

Data from Sveriges meteorologiska och hydrologiska institut, used under CC BY 4.0.

Suggested citation for Hydrionis

Hydrionis (2026), Olandsån gauge records, accessed 2026-10-05, hydrionis.com/waters/sweden-olandsan/

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 Olandsån 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 confidence1959-10-31

Source: SMHI — Swedish hydrological observations, 1256. Licence: Open — attribution required (attribution required).

Method: Daily discharge exactly as SMHI publishes it, from its corrected archive. SMHI computes the daily value from its own sub-daily 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.

Every value is checked and approved by SMHI. Station in the OLANDSÅN main drainage basin, 577 km². Discharge is a property of this gauge and this reach, not of the river as a whole.

Retrieved 1 October 2026.