The Grand Canal of the Château de Fontainebleau, model for the grand canals of French royal gardens
The Grand Canal of the Château de Fontainebleau was created under the reign of Henri IV, between 1606 and 1608, following the gardens of François I. A vast, 1.2 km-long body of water flowing from west to east, it has the distinct feature of being built partially above ground. With a surface area of 45,600 m² and a capacity of 140,000 m³, its scale is unprecedented in France, and it foreshadows the large canals developed in the second half of the 17th century at Vaux-Le Vicomte, Versailles or Chantilly.
The Grand Canal is a work of major importance not only for the hydraulic network, which irrigates the chateau’s gardens and the park, but also for the great Bellifontain landscape. It is the backbone of the historical gardens in the royal domain of Fontainebleau.
Classified as a Class C hydraulic structure by prefectural decree and, in its entirety, as a historical monument, it is also listed as a UNESCO World Heritage Site along with the chateau and its gardens. It belongs, just like the entire estate (chateau, gardens and park), to the State (Ministry of Culture) and is placed under the full and sole responsibility of the Public Establishment of the Château de Fontainebleau.
Essential work to restore the sealing of the Grand Canal
Following subsidence problems in 2008 at the eastern end, on the Avon side, a diagnosis highlighted watertightness problems on the eastern and northern dikes of this prominent heritage element, i.e. water reservoirs along the entire length of the canal on the city side, as well as at the level of the outlet where the canal empties on the Avon side.
In addition, the control structures that allow the emptying, dumping or managing overflows are fragile, impacting the masonry of the basins, which have undergone numerous deformations. Although regularly monitored and controlled since the initial measurements from 2009, the public establishment has noted that these degradations have sharply increased in recent years. Faced with this worrying state, the Château de Fontainebleau has decided to undertake the work necessary to restore the sealing of the Grand Canal. The technique that will be use specialized products and will restore the barriers back to the former watertightness. Over the centuries, these barriers have become permeable and no longer serve their function of containing the water of the canal. This work is therefore essential for the preservation of the Grand Canal, which is a major architectural element of this preserved historic landscape and a popular site for visitors.
Initially, a temporary dam, called cofferdam, will allow the Grand Canal to partially dry up and permit intervention. It will be positioned 200 meters from the end of the canal on the Avon side and will involve preventive fishing so that all the fauna is preserved and moved upstream of the dam. Ecological monitoring of the water quality, aquatic flora and the fauna will be carried out throughout the work, which is part of a committed approach that favors the environment by minimizing the impact on the flora and fauna, both in the choice of materials used and in the respect of the ecosystem. This preparatory stage will also involve the removal of several dangerous trees that are suffering from an incurable disease and have roots that have significantly damaged the sealing system of the dike to the east. These alignment plantings will be replaced as part of the master plan for the renovation of the gardens and the chateau park. In a second phase, the masonry of the dikes and hydraulic structures will be restored and strengthened. Finally, the dam will be removed, and the Grand Canal will be completely filled with water. The surroundings will be restored so that they can once again be visited by Bellifontains and visitors.
The operation, which is expected to last 12 months, is placed under the project management of OPPIC (Opérateur du Patrimoine et des Projets Immobiliers de la Culture). The Project management is conducted by Patrick Ponsot, chief architect of historical monuments.
Visitor traffic modified to facilitate restoration work
For safety reasons, the Allée de la Reine, which runs along the Grand Canal to the north, will be closed to the public during the restoration, and it will be reserved for the movement of construction machinery. An area to the east of the Grand Canal, around the outlet on the Avon side, will also be fenced off during the restoration process.
Aside from this limitation of access to the Grand Canal, the chateau park will remain open for the duration of the restoration work, every day for 24 hours. Visitors to the chateau and its gardens will rediscover the delight of touring the Grand Canal in Autumn 2023.
An area to the east of the Grand Canal, around the outlet, will also be closed off while this restoration operation is carried out. It will therefore no longer be possible to go around the Grand Canal completely. The majority of the park, however, will remain open, under current conditions, every day for 24 hours.
