Data access


Our data base contains time series over water levels of large rivers, lakes and wetlands around the world. These time series are mainly based on altimetry data from Topex/Poseidon for rivers, but ERS-1 & 2, Envisat, Jason-1 and GFO data are also used for lakes. At present, water level time series of about 100 lakes (in Europe, Asia, Africa, North and South America) including Aral & Caspian seas are available. About 250 sites (called virtual stations) on large rivers are also available (see maps below).

Users of the data base can visualize the water level time series as well as Landsat images showing the geographic location of the site. Users can download the numerical values of the time series as well as associated errors.


Theia contact for HydroWeb project :

Scientific contact for lakes :

Scientific contact for rivers :


Name : ERS-1, Topex/Poseidon, ERS-2, GFO, Jason-1, Envisat, Jason-2, Saral/Altika

Imaging mode : Radar altimetry

Spectral bands : Ku band (~ 2 cm wavelength)

Observation capability :

  • Swath : 100 to 500 m
  • Revisit : 10 to 35 days

Coverage :

  • Area : Global
  • Period : 1992 to present


The user can display the time series and access the numerical values and associated errors. Data are provided in a text format easy to exploit.

The content of time series is described in the user’s manual for products, accessible under the tab “Links”.


Please quote the following references for any use of these data :

References for river data

References for Lake Data

Download the licence in English and in French in pdf format

Useful documentation

Hysope poster presented at Hydrospace2015


Hydroweb Handbook