The deposit built by Josep Fontseré in 1874 combines the virtues of good construction, the ease of adapting to changing uses and the ability to understand and improve the place where it is located. A great example of good architecture.
The building was in perfect physical condition after being used as a pavilion at the International Fair of 1888, and it later housed a hospital, a municipal warehouse, a movie set and also became an important resting place for many migratory birds.
The project proposed demolishing all the interior divisions, the central part of the intermediate slab, and opening five skylights in the geometric centre of the roof that balanced the perimeter light and established a visual and kaleidoscopic relationship between the interior and the roof. For safety reasons, the large body of water that had been planned to be stored was never allowed to reach the top edge of the tank and the new proposal replaced it with a thin sheet at the top. This improved the old image of the permanently half-empty pond and solved the problem of vertical loads, seismic actions and tightness by reducing the weight and forming an intermediate security camera between the bottom of the new vessel and the old one.
As for the interior, two elaborate prefabricated pieces of concrete, one as a slab and the other as a support, organised discontinuous mezzanines three metres high above the floor of the room. Treated as furniture in the huge space, they increased the area of use, contained all the voluminous facilities that the building needed and gave rise to a great diversity of reading spaces, from some very collected and homely to others with wider views and spectacular heights.
With the exception of the new skylights, everything, including the new pond, was delicately superimposed on the building without injuring it. Everything could be dismantled so that the original support appeared intact again. The search for the formal expression of this strategy guided the project in all its aspects. Again, an exercise that reflects the relationship between architecture and decoration.
The refurbishment turned the water tank into the Pompeu Fabra University Library, located in the neighbouring barracks. It values the space by arranging it inside in the form of a completely removable intervention. The upper floors are made up of a system of prefabricated concrete pieces supported directly on the floor. The set is treated like a large piece of furniture that enhances the beauty of the interior space. The centre of the space is left empty, with the tables directly under the vaults. It is pleasant to visit the interior and check the power of this central space and, by contrast, the warmth of the corners that form the various small reading rooms.