Saint-Nazaire, France

Alvéole 14

Transformation of a submarine base

Lin - Finn Geipel + Giulia Andi Architects

The raw, impressive existing structure was transformed with minimal interference. The project consists of two elements: LiFE and VIP. The street traversing the entire base creates interaction between the bunker cells.
The hall for the international centre for emerging art forms (LiFE) is a minimalisti-cally equipped “monospace”. It is situated in a former submarine basin and can be opened up towards the harbour through a large, retractable gate.
VIP, a “venue for contemporary music”, occupies one of the volumes inside the bunker. A hall for 600 people was created in a simple cubic space enclosed by a steel frame, which also contains a bar, a balcony, and an archive.
A suspended “light carpet” covers the internal street running along former tracks. The street connects the various spaces already in existence with newly created spaces. This “gallery” possesses an enig- matic atmosphere.
A staircase leads from the gallery, through the roof, to an experimental platform. A geodesic dome from the Berlin Tempelhof Airport serves here as a “think tank” for art and music projects.

The harbour and the submarine base
The submarine base is located directly at the harbour of Saint-Nazaire at the mouth of the Loire River, about a kilometre from today’s city centre.
Before the Second World War, this harbour was at the heart of the town centre. Transatlantic ocean liners set sail for South America from here.
The bunker was built exactly on this port basin between 1941 and 1943 under “Organisation Todt” as a submarine base for the German Navy.
The scale of the bunker is enormous: 295 metres long, 130 metres wide and 15 to 19 metres high, covering an area of 3.7 hectares. The roof is made of reinforced concrete and is as thick as 4 to 9 metres.
The base is split into 14 submarine cells (alvéoles), of which eight were designed as dry docks and six as water basins. The basins are 11 metres high and 117 metres long, while the tanks inside measure 17 metres by 90 metres.
The cells are connected inside through an intersecting “street” equipped with tracks. They were used originally for the transportation of machine parts.

The submarine base and the city
The central location in the old town made it the target of air raids from 1942 onwards, which destroyed 85% of the city.
Reconstruction of the city began in 1949 further away from the harbour under the di- rection of the architect Noël Le Maresquier. The virtually unscathed bunker remained a powerful obstacle between the city and the harbour.

Project “Ville-Port“
Since the 1990’s, the city of Saint-Nazaire has made efforts to revive the histori-cal link between the city centre and the harbour.
In 1991, lighting artist Yann Kersalé il-luminated the industrial harbour with his project, “Nuit des Docks”
In 1994, the urban planning project “Ville-Port” was started. Joël Batteux, the mayor of Saint-Nazaire, declared the base as central to the future development of the city.
In the first phase, under the direction of the Barcelonean architect, Manuel de Solà-Morales, four cells at the centre of the bunker were opened up and the roof was fitted with a ramp accessible to the public.
At present, there are various projects under development on either side of the harbour, each encompassing different uses of the site (residential, commercial, and cultural). The second phase of the project “Ville- Port” is due to be completed by 2012.

Project “Alvéole 14“
This project seizes the site’s intrinsic qualities. The raw, impressive structure is transformed through minimal interference, enhancing the enigmatic atmosphere of the bunker cells. The cells are accessible from the outside through just a few en-trances and the roof has also been made accessible. The capillary nature of these transformations contrasts starkly with the monolithic character of the existing space. The bunker becomes a site suitable and appealing for new uses.

Project elements
Street
New flooring and a “light carpet” define this public street running along the former tracks. The street connects the public spaces created by the project “Ville-Port I”(Ocean liner museum “Escal’ Atlantic”, Cells 8-11) with the new project in Cell 14, opening up the possibilities of new uses as it leads through the bunker.

International centre for emerging art forms (Lieu international des Formes Emergentes) – LiFE
The hall for this centre for new art forms is a former submarine basin covered with reinforced concrete beams and concrete flooring. The hall can be opened up towards the harbour through a large, re- tractable gate. This “Monospace” has been equipped minimalistically and is thus open to be adapted to future forms of art.

Venue for contemporary music (Scène de Musiques Actuelles) – VIP
As the street runs through the bunker, it approaches VIP’s “cube dense”, a three- story steel construction. VIP is to become a central hub of the action in the bunker and includes an event hall, a bar, an archive and several recording studios.

The roof and the radome
The bunker is intrinsically ambivalent: it is at once a barrier and a hub. By invigorat-ing the roof through a focal visual point and making it visually approachable, it has the potential to become one of the most important public sites of the city.
The radome and the outside platform are positioned on the roof. An opening in the bunker ceiling connects them to the inside of the bunker via a large stairway.
The radome is a geodetic dome construc-tion. It was in use as a covering for the strategic radar unit at the Berlin Tempelhof Airport from 1984 until 2003. Its aluminium frame makes up 298 triangles, each cov-ered with a translucent membrane.

Europaconcorsi Beta

Alvéole 14