We are delivering stream flow data every year to the EEA, under the WISE SoE - Water Quantity (WISE-3) data stream http://cdr.eionet.europa.eu/help/WISE_SoE/wise3 . I guess other countries are doing the same. You should be able to retrieve this data one way or the other from the EEA databases.

You can download data for some of the flow gauges I the UK from the National Flow Archive see: http://nrfa.ceh.ac.uk/

Irish river flow records can be accessed and downloaded from: http://waterlevel.ie/hydro-data/home.html and http://www.epa.ie/hydronet/#Water%20Levels

In Spain, you can download daily data from the national flow gauges database:

http://ceh-flumen64.cedex.es/anuarioaforos/default.asp

For France, you can get the data from  http://www.hydro.eaufrance.fr/.

Hi

the MEDFRIEND/UNESCO program gives meta data about rainfall and discharges existing time series

http://armspark.msem.univ-montp2.fr/medfriend/index.asp?menu=Pays_list

You can then ask the website responsible

[email protected]

to authorize access to the data.

Best

Gil