marine submersion
territory resilience

On the Marais de Brière site in Saint-Nazaire, an area of transition between the city center and its Grand Port Maritime, the urban study carried out by ANMA proposes adapting urban and architectural forms to cope with the risk of marine submersion.

With the support of Urban Water and Algoe, the agency is looking to the future of the area to rethink the coherence of the landscape and the urban environment, in order to cohabit with the natural cycle of the sea.

Covering an area of 500 hectares, the project involves two levels of reflection: a long-term approach to the programming and urban transformation of the city’s northern entrance; and a more micro-scale approach, focusing on specific transformations through short-term operations.

Extension of marshland
Natural water cycle

The long-term vision is to restore the artificial, impermeable soil to its role as a sponge against flooding. The project recreates a wetland area as close as possible to the biotope of the neighboring marsh, restoring water to its original place and role – in the service of the site’s biodiversity.

This extension to the Brière marshes will be able to receive water from the sea and runoff, as it has been designed as a natural hydraulic machine through the renaturation of the site.

Short-term changes are located in this at-risk zone, and incorporate the main hydraulic principles of the natural cycle of the sea in the area. The requalification of the Grand Large commercial zone and the new Halluard Gautier district are being developed as the first step in adapting this area to the risk of submersion, as a vector for renaturation and new architectural principles, adapted to the risks.

New neighborhood
New uses

For the Halluard-Gautier district, ANMA and its team have drawn up a development plan that supports risk management and the diversification of uses. The agency set out the principles of a neighborhood that would reconstitute fertile soils to ensure resilience to flooding:

– Creation of artificial embankments to recover the alluvial deposits of the Loire
– Deconstruction of hangars to give nature back its rightful place
– Raising of ground-floor houses
– Construction of buildings on stilts
– Reintroduction of soft mobility

PROJECT TEAM

PROJECT MANAGEMENT
Urban planner: ANMA
Programming: ALGOE
Hydraulics: Urban Water

STUDIES
Agrippa Leenhardt
Pierre Bouilhol
Sébastien Moinet

TECHNICAL SHEET

MISSIONS
Programmatic and urban coherence study for the northern part of the conurbation

Pre-operational study of the Halluard-Gautier district, to make it resilient to marine submersion

Study on the redevelopment of the Grand Large commercial zone

Urban feasibility of program insertion

PROJECT MANAGEMENT
ADDRN

SCHEDULE
2019-2022

AREA
500 ha

SEE +
Annecy, Imagine and Draw Greater Annecy
Bordeaux, Bordeaux 2050
Toulon, Parc universitaire de la Garde la Valette