Located on the banks of the river Seine, the building fits in with the history of the site and the continuity of the existing hangars, which feature the same volumes. The programme integrates the highly defined envelope of the hangar: it asserts the identity of the Agence de l’Eau (French Water Board) and creates a showcase for its missions to preserve water resources while proposing a highly contemporary architecture in its overall implementation and its specific interior design. The building’s facades and volumetry respect the local requirements: a brick construction with visible metallic framework. The vertical openings follow the rhythm of the porticos. The building is cooled thanks to natural night-time ventilation, a passive system that provides guaranteed comfort in summer: at night, cool air enters via apertures, transits through the offices and is evacuated via the top of the atrium. The full-length skylight in the roof features high-performance glass that provides natural light for all the volumes.
The offices are located on either side of the atrium and accessed via a walkway. The reception areas are clearly defined, with abundant natural overhead light and ventilation bringing environmental quality. We undertook careful studies to make the overall office plan flexible and develop communication areas between the different services. Steel walkways with wooden decks cross and link the open atrium on all levels, supplemented by metal staircases in the central space. This interconnection between the stairs and the bridges enables multidirectional circulation. The architectural approach is characterised by a unique element that is visible on entering the building: an inclined plane slopes down the full length of the building from the first level to the ground level. This sloping slab, down which a thin film of water flows, actually provides an additional thermal regulation system. It is in scale with the building, helps to enhance the interior spaces, and offers varied perceptions of the volume of the atrium. The artist Emmanuel Saulnier created an artwork entitled
Fils d’eau for this space: on the watery slope he placed a number of glass tubes, also filled with pure water, that create an intriguing play on shifting ripples of light.