On the lake of Grand-lieu itself, only professional fishermen are authorized. The reason for this drastic limitation is the Natura 2000 classification of the lake and the will to make it a protected natural space. However, the adjoining rivers and the surroundings of the lake are open to boaters.
The geography of the place is extraordinary. From 37 square kilometers in summer, the lake increases to 65 square kilometers in winter, due to the particularly shallow nature of the water. It thus creates the second natural ornithological reserve of France during the winter season.
Moreover, more than a lake, it is a lacustrine whole that constitute the lake of Grand-Lieu, the Tenu, the Ognon and the Achenau. These 3 rivers feed or are used as outlets for the lake.
Surprisingly, the Achenau is the only river in France that does not always flow in the same direction. In winter, it receives its water from the lake and, in summer, its water is pumped to feed the lake and the Breton-Vendée marsh and keep it level.
The lake itself is not open to navigation, unlike the three rivers that border it, the Ognon, the Acheneau and the Tenu, which welcome boaters.
Conditionally donated to the state
The lake of Grand-lieu was given by the perfumer Guerlain to the state at the end of the seventies with several conditions:
- That the water body remains natural, without navigation
- That Mr. and Mrs. Guerlain, accompanied by 3 guests, are the only authorized hunters
- That only the professional fishermen already installed on the lake remain the only ones entitled to it
Once these clauses were met, the State became the title owner of the vast majority ( two thirds ) of the lake in the early eighties.
Non-navigable, the lake itself is a haven of peace for walkers. A long-distance hiking trail circles the lake. The 70 kilometers are easy enough, but the path is only partially accessible to people with reduced mobility because of the flooded nature of the lake's shores, which remain free of any development.
" This is not the case for the Tenu, the Ognon and the Achenau "explains Alexis Laforge, who owns the company Nature getaway . The two nautical bases he manages offer boat rentals on the surrounding rivers of the lake.
The guide's advice
" The lake is kept slightly accessible to the public, so that it does not become a full-fledged attraction " explains Alexis. " For this reason we are developing, in relation with the public authorities, soft offers on the surrounding rivers, creating a river-lake complex that brings to the lake or allows to come from it. The idea is not to create too much ecological pressure on the environment."
Navigation on these two rivers is open and free. The speed limit is 6 kilometers per hour is rarely achieved: " Many fishermen are at the water's edge or sometimes even with their feet in the water. Shallow (about 40 centimeters), these rivers are also accessible by foot. Boaters should keep in mind that the routes are shared. "
Most of the towns and villages we visited offer the minimum of services In Saint-Père, there are supermarkets, pharmacy and all the shops. Including fuel, for the few boaters who would come with a thermal engine. "
These engines are not prohibited in this protected area. " But they are not welcomed or encouraged" insists the manager. "The idea is not to reject them at all costs, but to insist on the calm and relaxed aspect of the place, which requires that everyone pay attention to the well-being of the other. "
The other side of the coin is that many boaters operate electric engines without the infrastructure to recharge the batteries being in place.
Navigation on this lake complex is easy and peaceful There is almost no current on the Achenau in summer, a little more in winter. Beware, however, that some algae may interfere with navigation "adds the guide.
" Gentle users, walkers as well as fishermen have priority on the rivers. And birds and fauna have absolute priority over boats, no question of disturbing them "ends Alexis.
The ferry between Port-Saint-Père and Saint-Léger-les-Vignes makes it possible to cross from one bank to the other in a fun and ecological way. It is thus possible to moor one's boat on one side or the other of the river and to use human energy for this crossing. In addition to being fun, this way of crossing is free.
The Pont-Saint-Martin water sports center, on the Ognon river, offers kayaks, canoes and boats for rent, by the hour or by the day.
In Port-Tréjet, still on the Ognon, the rental of a flat boat offers an amazing experience of navigation in the old way, on a flat-bottomed boat.
Lovers of old stones will not miss to visit the oldest monument of Loire-Atlantique, the site of the abbey Déas, in Saint-Philbert-de-Grand-Lieu.
Local tips and tricks
" The binoculars are an essential accessory on the lake and around, to be able to watch the fauna without disturbing it "we explain. They are available for rent at the nautical base.
You can launch your boat in Port-saint-Père and Saint-Mars de Coutais without any difficulty for small boats. The shallow draft ( 60 centimeters at most ) does not allow the navigation of large boats, which the size of the complex cannot accommodate.
" Each slipway has sufficient parking space for cars and trailers "adds the manager. Composed of closed waterways, the only way to reach these rivers is via these boat slips.
On the lake, do not miss the lake house the Guerlain Pavilion, also known as the Guerlain Pavilion, presents the local ecosystem as well as the vast surrounding animal reserve. A few steps away, the bell tower of Sainte-Lumine dominates the lake and its tributaries.
A little further away in Port Hammoneau, the picnic area allows you to moor your boat and disembark, in the middle of nature and without the risk of being bothered. This is one of the favorite spots of the person in charge " especially at sunset "he adds.
Finally, because the agapes are never far away, do not forget the restaurant Le Saint Georges or the Auberge du pays de Retz, both located in the town of Port-Saint-Père.
