We make our way into our fourth country of this year’s Tour today, running through the valleys of the Jura before arriving in the Swiss capital, Bern. Along the way, we pass the largest lake entirely in Switzerland, the Lac de Neuchâtel or the Neuenbergersee.
Lake Neuchâtel is, like the others around it, a glacial lake, exposed after the end of the Würm glaciation around 12,000 years ago.
The lake was naturally oligotrophic with low biological production and good water quality. Human impacts increased the phosphorus load into the lake until the 1980s when Swiss water treatment plants began removing phosphorus and phosphorus detergents were banned (Lang 1999). Since then, the lake has recovered to an oligotrophic condition.
The reed marshes on the less-developed south bank of the lake are a Ramsar wetland, as is the shallow bay and marshes between Cudrefin and the Thielle canal which connects Lake Neuchâtel to the Lac de Bienne.
And wouldn’t you know? Peter Sagan did it again with a very close sprint win over Alexander Kristoff. A rest day for the riders and Les Eaux tomorrow before we start our course through the Alps.
- Lang, Claude. “Contrasting responses of oligochaetes (Annelida) and chironomids (Diptera) to the abatement of eutrophication in Lake Neuchâtel.”Aquatic Sciences 61, no. 3 (1999): 206-214.