Rhine basin: Low flow monitoring by the International Commission for the Protection of the Rhine

Hintergrundbild Rheingebiet
Rhein - Diepoldsau
Rhein - Rekingen
Rhine - Basel Rheinhalle
Rhine - Maxau
Rhine - Worms
Rhine - Mainz
Rhine - Kaub
Rhine - Andernach
Rhine - Cologne
Rhine - Lobith
Link to the ICPMS low flow monitoring.
  • Current flow at gauge has not yet fallen below the 2-year NM1Q threshold.
    no low flow / very frequent low flow (Q ≥ 2-year NM1Q)
  • Current flow at gauge has fallen below the 2-year NM1Q threshold, but not yet undershot the 5-year NM1Q threshold.
    frequent low flow (Q < 2-year NM1Q)
  • Current flow at gauge has fallen below the 5-year NM1Q threshold, but not yet undershot the 10-year NM1Q threshold.
    less frequent low flow (Q <5-year NM1Q)
  • Current flow at gauge has fallen below the 10-year NM1Q threshold, but not yet undershot the 20-year NM1Q threshold.
    rare low flow (Q < 10-year NM1Q)
  • Current flow at gauge has fallen below the 20-year NM1Q threshold, but not yet undershot the 50-year NM1Q threshold.
    very rare low flow (Q < 20-year NM1Q)
  • Current flow at gauge has fallen below the 50-year NM1Q threshold.
    extremely rare low flow (Q < 50-year NM1Q)
  • There are no up-to-date flow data available.
    no up-to-date flow data
  • ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  • Trend (water level at gauge):
  • The water level at the gauge has risen more than 10 cm in the last 4 hours.
    rise of more than 10 cm in 4 hours
  • The water level at the gauge has risen more than 5 cm in the last 4 hours.
    rise of more than 5 cm in 4 hours
  • The water level at the gauge has risen / fallen up to 5 cm in the last 4 hours.
    rise / fall up to 5 cm in 4 hours
  • The water level at the gauge has fallen more than 5 cm in the last 4 hours.
    fall of more than 5 cm in 4 hours
  • The water level at the gauge has fallen more than 10 cm in the last 4 hours.
    fall of more than 10 cm in 4 hours

The monitoring of the occurrence of low flow (low water) and its classification is carried out by comparing current flows at the gauge with threshold values of the NM1Q (lowest daily mean) or for the low water duration via the comparison of the current 7-day mean with the threshold value of the NM7Q (lowest mean flow value of 7 consecutive days) of the reference time series 1961-2010 for statistical return intervals of 2 to 50 years - see ICPR Report No. 248.
With the uniform ICPR low water monitoring on the entire Rhine (see details in ICPR Report No. 261), current low water events can be directly classified in a comparative manner and possible changes in low flows can be detected.
In addition, the total duration and also the duration of the low flow classes that were reached are given for the most recent low water event. Maps of the Standardized / Normalised Precipitation Index (SPI) and the Soil Moisture Index (SMI Anomaly) are displayed to help categorise the drought. Furthermore, the current water temperature and oxygen content are provided for selected water quality measuring stations. Additional data is available on the Undine information platform, a. o. here.

Underlying data: Wasserstraßen- und Schifffahrtsverwaltung des Bundes [DE] (Pegelonline) / Rijkswaterstaat [NL] (Waterinfo) / Federal Office for the Environment FOEN [CH] (Hydrological data and forecasts ) / Bundesanstalt für Gewässerkunde.
The time of the water levels / flow rates is given in CET (winter time). No liability or guarantee is assumed for the up-to-dateness, correctness and completeness of the information and data provided.

Duration of the last or current low flow event and of the low flow classes in days (status: ) - Test operation -

GaugeStart phaseEnd phase*Total durationFrequent low flowLess frequent low flowRare low flowVery rare low flowExtremely rare low flow
Diepoldsau (Alpine Rhine)
Rekingen (km 90,76)
Basel (km 164,27)
Maxau (km 362,3)
Worms (km 443,4)
Mainz (km 498,3)
Kaub (km 546,2)
Andernach (km 613,8)
Cologne (km 688,0)
Lobith (km 862,22)

* If the low flow classification value is exceeded for a maximum of two days, the low flow phase is not terminated. In the case of currently ongoing low flow phases, the previous day is entered as the end of the low flow phase, since the classification is based on 7-day moving averages. A dynamic update takes place on the respective following day.

Water temperature of the Rhine at water quality monitoring sites - raw data -

Diepoldsau (Alpenrhein)
Rekingen (km 90,8)
Weil am Rhein (km 171.4)
Karlsruhe (km 359.2)
Koblenz (km 590.3)
Bad Honnef (km 640.0)
Bimmen-Lobith (km 865.0)

Oxygen content of the Rhine at water quality monitoring sites - raw data -

Diepoldsau (Alpenrhein)
Rekingen (km 90,8)
Weil am Rhein (km 171,4)
Karlsruhe (km 359,2)
Koblenz (km 590,3)
Bad Honnef (km 640,0)
Bimmen-Lobith (km 865,0)

Standardized Precipitation Index (SPI) for the 6 preceding months

Soil Moisture Index (SMI Anomaly/SMA) for the last available 10-day period

Low flow & drought