Swimming across lac Léman

AKA Lake Geneva to the English

During the heatwave last week (first week of July 2015) we decided to take the opportunity of a very warm Lac Léman  to swim from France to Switzerland. We are not superhuman so we left the “classic” traverse from Evian to Lausanne alone (13km) and headed for the narrowest section instead. From Nernier to near Prangins (3.5km according to the map)

Nernier is a small quiet and picturesque little village. The is minimal parking available so get there early in the holidays. We arrived at 9.30am and found somewhere fine. You can drive down to the water’s edge if you need to drop off a boat but it’s not easy and best avoided. There is a public toilet at the Port if you need one.

We were a little worried about the various hazards the lake can present. We’d checked the weather forecast and there were no strong winds likely, go before 10.30am and the lake is most likely to be mirror smooth too. After this time the thermic breezes will start up adding some ripples. There is a regular ferry service which doesn’t like to give way to anything but it’s only an issue close to the port of Nernier, if you don’t set off or arrive as it is docking or leaving it should not be an issue.

The temperature of the lake changes very quickly. Up to 2 °C from the morning until the evening on a hot day. It’s easy to gauge with this website though.

http://meteolakes.ch/#!/hydro/geneva

The figure you need is the “Température eau 1m”. On our day it was 21 °C which was fine without a wetsuit. The only hazards we encountered where the occasional small wakes from passing boats.

The headland we landed on is private land, there was noone around though and it’s not overlooked. There is a sign which politely asks that you don’t venture beyond the beach.

We used a GPS to track our actual route, this is my return swim (the two of us took turns swimming and paddling the canoe), we had been heading towards the wrong landmark so had to change direction half way! According to the GPS it was a 4km swim which took 1hr 15min.