Information about the 21.5km long river Sèvre Nantaise

Sevre Nantaise map France

The Sèvre Nantaise, a part-tidal, part-canalised river, is navigable over a distance of 21.5km from its confluence with the Loire at Pont-Rousseau (a suburb of Nantes) to Monnières bridge. Together with its tributary, the Petite Maine, which is navigable over a distance of 6 km up to the first (disused) lock at Pont Caffino, in the village of Chateauthébaud, the Sèvre Nantaise is a most attractive navigation, especially in the upper reaches beyond Vertou lock. It offers many attractive moorings in the heart of the Muscadet wine-growing area. For convenience, the distance table is presented working upstream from its confluence.Region Map Sevre Nantaise

History – This tributary of the Loire, with its gentle gradient, lent itself to canalisation to give the local population convenient access to Nantes and to transport stone for building in the city. The weir (Chaussée des Moines) and lock were built at Vertou in the late 19th century, and passenger steamers operated until the 1930s. The half-tide weir at the confluence was built in the 1980s, replacing the impractical earlier sluice-gates. The navigation now belongs to the Brittany region.

Key Waterway Dimensions

  • Max Beam: 5.50m
  • Max Height: 4.00m
  • Max Draught: 1.20m

Local Waterway Links


Delightful navigation, once through the restricted entrance from the river Loire. Access to the Sèvre Nantaise is via a half-tide sluice 200m in from the confluence (Pont-Rousseau), which is open from one hour before to one hour after high tide.

Locks – On the Sèvre there is just one lock, situated at Vertou, with a length of 31.50m and a width of 5.50m.

Draught – From the confluence with the Loire to Vertou lock the river is tidal, but the depth ranges only slightly following construction of the Pont-Rousseau tide-sluice at the confluence. Depths are generous compared to the maximum authorised draught of 1.20m. On the Petite-Maine the maximum authorised draught is 0.90m. Headroom – There are several fixed bridges. The lowest headroom is at the Pont-Rousseau sluice structure, which limits access to boats with an air draught of 4.00m. Towpath – There is no towpath. Authority – Syndicat de rivière Sèvre aval (manages the waterway on behalf of the Conseil départemental Loire-Atlantique)
Moulin de Nid d’Oie – 10bis route de Nid d’Oie – CS 49405, 44194 Clisson Cedex
Click to enlarge

Route description

PK 0.0    Confluence with the Loire (PK 85.3)
PK 0.2    Rézé tidal sluice The sluice (central passage) is to be passed between 1hr before and 1hr after high tide. There is a 12m long waiting pontoon on the left bank just inside from the confluence, 130m before the sluice gates (see photo). PK 0.2    Pont-Rousseau quay l/b
PK 0.3    New bridge (Pont-Rousseau)
PK 0.3    Old bridge (Pont-Rousseau), tram lines 2 and 3, moorings u/s l/b, trip boat
PK 2.0    Bridge (La Morinière)
PK 2.1    Port des Lys pontoon moorings l/b
Sevre Nantaise Pont-Rousseau
Modern flap gates replaced the inadequate sluice structure at Pont-Rousseau in the 1980s, making the Sèvre Nantaise much easier to enter from the Loire (in the background, with the Béghin-Say sugar factory towering on the far bank.  © Luminem

PK 2.5    Bridge (des Bourdonnières)
PK 2.8    Overhead power lines
PK 3.1    Bridge (motorway spur to Nantes town centre)
PK 3.5    Beautour quay r/b
PK 4.1    Bridge (N844, Nantes ring road)
PK 4.5    Overhead power lines
PK 5.2    Château (Portereau), l/b
PK 6.7    Vertou lock and weir (lock in r/b arm)

The restaurant ‘L’Écluse’ right beside the lock is one of many in this very popular week-end retreat for the people of Nantes. The weir, called the Chaussée aux Moines, winds across the broad river and during low flow periods is used as a ford to walk across. The river becomes even prettier upstream from Vertou. PK 7.1    Le Chêne bridge, moorings d/s l/b, water, electricity, Vertou 1000m r/b
PK 4.5    Portillon bridge, moorings u/s l/b

Sevre Nantaise Vertou lock
The upper gates of Vertou lock and the Chaussée aux Moines ,
more ford than weir during the summer. © Luminem

PK 11.1    Confluence of Petite-Maine l/b, navigable upstream 6.0km to Chateau-Thébaud
PK 11.6    Bridge (Ramée), D59
PK 15.0    La Cantrie moorings l/b
PK 16.1    La Haie Fouassière bridge, moorings d/s r/b, water, village 1000m
PK 21.0    Port Domino quay r/b
PK 21.5    Monnières bridge, head of navigation

The stone bridge marks the end of the waterway.

PK 0.0    Confluence with Sèvre Nantaise
PK 0.3    Château (Le Coin), r/b
PK 4.3    Saint-Fiacre-sur-Maine bridge, moorings u/s r/b

sevre-nantaise-stone bridge
The stone bridge at Monnières carries the only navigation sign to be seen on the river (apart from the Pont-Rousseau sluice structure) : the no-entry sign indicating the end of the waterway. © Frédérick

PK 5.9    Château-Thébaud bridge (Pont Caffino), quay d/s r/b, village 500m l/b
PK 6.0    Disused lock (Pont Caffino), head of navigation

Sevre Nantaise chateau du coin
The château du Coin, just 300m up the Petite-Maine, showing the potential navigational hazard of tree trunks. © Jeapil