Lake area
Length of the banks
Maximum depth
Average volume
Average altitude
of the water body
Dwell time
theoretical waters
Watershed area
from Lake Geneva*
Permanent population
in the watershed**
*The Lake Geneva watershed is the entire territory where surface water flows into Lake Geneva. It extends mainly across Switzerland (cantons of Vaud, Valais, Geneva and Fribourg) and France (departments of Haute-Savoie and Ain). It is fed by several rivers, including the Rhône , its main tributary, as well as the Arve, the Dranse, the Venoge and the Aubonne.
**Data for France: 2017 – Data for Switzerland: 2018
In spring, the lake's water quality measurement campaigns become fortnightly once again, in order to monitor the warming of the water and the resumption of algae growth in suspension in the water.
Winter mixing has resulted in the remobilization to the surface of the nutrients required for algal growth (mainly nitrogen and phosphorus). Spring warming, combined with increased solar radiation, allows algae growth to resume in the nutrient-rich surface layer. The resumption of algae growth is accompanied by a drop in surface water transparency.
Algae are important to the functioning of the lake, forming the basis of the food chain. Most of them pose no problem, but some species are problematic: those that clog fishing nets, and toxic cyanobacteria.
Rising air temperatures and longer daylight hours cause surface waters to warm up to depths of around 30 m.
Discover the fascinating real-time dynamics of the waters of Lake Geneva thanks to two innovative models, designed by researchers in the region, revealing the movements and temperatures of the lake.
Discover the latest temperature, Secchi transparency, turbidity and chlorophyll a concentration measurement data and their evolution.
