The monitoring network within this area

Hydrionis holds 120,911 values from 8 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.

8
Gauges
120,911
Values held
1909–2026
Record spans
3,591 km²
Area
Gauges within the Nyköpingsån drainage basin
8 monitoring points, positioned as the publisher records them.
Gauges within the Nyköpingsån drainage basinBJURSTORP, CHRISTINEHOLMS REGL.DAMM, HALLBOSJÖN, HEBYLUND KVARNSJÖN, NEDRE TÄCKHAMMAR, SIBRO, SIBRO 2, VARBROBJURSTORPCHRISTINEHOLMS REGL.DAMMHALLBOSJÖNHEBYLUND KVARNSJÖNNEDRE TÄCKHAMMARSIBROSIBRO 2VARBRO

The longest record here

Mean river flow at HALLBOSJÖN
Annual means of the daily record, 1934–2025. One gauge, not this drainage area.
Mean river flow at HALLBOSJÖNMean river flow at HALLBOSJÖN: HALLBOSJÖN in m³/s, from 1934 to 2025.05101520m³/s19341946195819701982199420062018

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
PeriodHALLBOSJÖN (m³/s)
19346.12
193513.3
193616.8
193713.0
19389.48
193911.7
19407.04
19416.43
19427.32
194310.5
194417.7
194516.2
194613.0
19478.06
19484.75
19493.85
195012.4
195114.8
195211.2
195311.8
195410.0
195511.8
19568.03
195710.8
195815.6
195916.6
196014.6
196115.3
196215.5
19639.89
19647.01
19659.17
196615.9
196717.9
196812.9
196912.2
19709.02
19718.42
19729.60
19736.01
19749.93
197514.7
19761.46
197715.4
197815.2
197912.2
198011.9
198116.7
198214.7
198310.8
198410.7
198517.2
198616.1
198713.1
198817.0
19896.68
19905.98
19919.57
19926.69
19938.38
199412.3
199517.0
19968.61
199710.7
199816.0
199915.3
200017.0
200118.7
200211.9
20034.51
200410.1
20059.52
200611.5
200712.2
200813.1
200911.6
201016.0
201112.4
201216.4
201313.1
201412.1
201512.3
20168.07
20172.84
20189.06
20194.45
20209.25
20219.58
20224.77
202314.3
202417.8
20257.81

Every gauge Hydrionis holds within this area

Gauges within the Nyköpingsån and what each holds
GaugeMeasuresValuesRecord
HALLBOSJÖNmean river flow33,9301933–2026
CHRISTINEHOLMS REGL.DAMMmean river flow31,5541940–2026
SIBROmean river flow15,7061975–2017
BJURSTORPmean river flow15,0091979–2020
NEDRE TÄCKHAMMARmean river flow10,7731909–1938
VARBROmean river flow5,9641979–1995
SIBRO 2mean river flow5,1372012–2026
HEBYLUND KVARNSJÖNmean river flow2,8382018–2026

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 — 65000. 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
HALLBOSJÖNStated by the publisher on the record this gauge’s observations came from.With the observations
CHRISTINEHOLMS REGL.DAMMStated by the publisher on the record this gauge’s observations came from.With the observations
SIBROStated by the publisher on the record this gauge’s observations came from.With the observations
BJURSTORPStated by the publisher on the record this gauge’s observations came from.With the observations
NEDRE TÄCKHAMMARStated by the publisher on the record this gauge’s observations came from.With the observations
VARBROStated by the publisher on the record this gauge’s observations came from.With the observations
SIBRO 2Stated by the publisher on the record this gauge’s observations came from.With the observations
HEBYLUND KVARNSJÖNStated 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 record8yes, 3 or more
Years spanned118yes, 20 or more
Values held120,911yes, 1000 or more
Distinct measurements1no
Publishers measuring it1no
Official identifiers2recorded, not counted

Where these figures come from

MeasuredMedium confidence2026-08-24

Source: SMHISwedish hydrological observations, 1273. 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.

Checked and approved by SMHI except 1933-10-01 to 1960-12-31 (not yet checked), 1979-06-07 to 1979-06-07 (not yet checked), 2026-02-12 to 2026-08-24 (not yet checked). Station in the NYKÖPINGSÅN main drainage basin, 1,992 km². Discharge is a property of this gauge and this reach, not of the river as a whole.

Retrieved 25 August 2026.