The export is currently suspended due to a technical issue and should return soon.
Full dataset of the wiewarm.ch website, containing many millions of temperature points from pools, rivers and lakes all over Switzerland.
The data is collected on the website http://www.wiewarm.ch either by manual entry or from sensors. Entries go back to 2001 when the website launched.
The temperature values are in degree celsius, and the file encoding is UTF-8 with "Unix"-style line feeds. Date format is YYYY-MM-DD hh:mm:ss. The CSV of the current year will be updated daily.
You can freely use this data according to Creatvie Commons Attribution-ShareAlike 3.0. See the wiewarm.ch info page for instructions how to properly attribute the source.