Ecluse à sas de Choiseau, située sur le canal d'Orléans
MonumentHidden Treasure
Ecluse à sas de Choiseau, située sur le canal d'Orléans, located in Coudroy (Loiret), is a Renaissance château built in the 16th century. The monument is currently closed to visitors.
Key facts
- Type
- autre
- Period
- Renaissance (16th century)
- Location
- Coudroy, Loiret, Centre-Val de Loire
- Visit
- Closed to visitors
- GPS
- 47.9040, 2.4644
- Mérimée Reference
- PA45000010
In the heart of the Beauce region, the Choiseau lock reveals the hydraulic ingenuity of the Grand Siècle: its aqueducts embedded in the walls and its rack and pinion valves make it a technical jewel of the Orléans canal.
© Wikimedia Commons / Wikipedia
History
Nestling in the tranquil greenery of the Loiret, at Coudroy, the Choiseau lock with sluice gate is one of the key components of the Orléans canal, an artificial waterway whose design dates back to the great river-related ambitions of the reign of Louis XIV. Far from being a simple piece of civil engineering, it embodies four centuries of hydraulic know-how and bears witness to the way in which 17th-century France sought to control its territories through inland waterways. What makes Choiseau truly unique is the sophistication of its technical system: the aqueducts are built directly into the bajoyers - the side walls of the lock - allowing the lock chamber to be filled and emptied without recourse to conventional surface valves. The gates are operated by a system of metal racks, the clicking of which used to be the rhythm of the lock-keepers' labours. The vent holes, cut into the Loire stone, remain in place, silent witnesses to a technology designed to last. The lock-keeper's house next door completes this vivid picture of a bygone era. Sober and functional, it is a reminder that for two centuries the canal was a vital economic artery, bustling with barges transporting wood, grain and tiles to Orleans and Paris. A visit to Choiseau is a reminder of the hard-working France of the watermen. For visitors, the experience doubles as a soothing stroll along the canal, lined with alders and poplars. Photographers and lovers of industrial heritage will find plenty to feast their eyes on in the reflections of the lock and the limestone texture of the stones. The peace and quiet of the site, far from the main tourist routes, makes it an ideal stop-off point for cyclists on the Vélo-Route du canal d'Orléans.
Architecture
The Choiseau lock is of the so-called "lock chamber" type, where two arched gates delimit an intermediate water chamber allowing boats to cross a difference in level by gradually filling or emptying. Instead of valves in the gates themselves, the bajoyers - the masonry side walls that contain the lock - are hollowed out with underground conduits through which the water flows silently. This system, which is gentler on boats and fragile goods, is operated by rack-and-pinion gates whose wrought-iron rods emerge above ground and are operated by hand by the lock-keeper using a special key. The vent holes, small circular openings cut into the stone, regulate the pressure in the pipes and are now one of the most moving archaeological features on the site. The masonry is mainly of Loire limestone, a material that is abundant in the region, carefully squared at the corners and facing, with rubble stone infill for the body of the beams. The distinction between the seventeenth-century sections and those rebuilt in 1823 and 1845 can be seen in the careful matching and slight variations in block modulus. The wooden swing doors, rebuilt in 1993 using traditional techniques, complete the ensemble with their carefully assembled oak beams. The lock-keeper's house, a sober single-storey building with a gable roof covered in flat tiles, is in the tradition of nineteenth-century Ponts et Chaussées service housing.
Related Figures
Colbert — ministre de Louis XIV, instigateur de la politique des canaux royaux qui donna naissance au canal d'OrléansFamille Hutin — entrepreneurs généraux chargés de la construction du canal d'Orléans à partir de 1676Ingénieurs des Ponts et Chaussées — responsables des rénovations de 1823 et 1845 sous la Restauration et la Monarchie de JuilletLouis XIV — souverain sous le règne duquel fut lancé le projet du canal d'Orléans (1676-1692)
