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Le Havre is the tenth largest container port in Europe and under the project of "Port 2000" the Port Autonome du Havre was realizing a major port extension for container vessels. The project presented itself with some challenges, one of which was to compensate for the loss of nature, or even to increase natural values. As part of the environmental compensation, a dedicated bird island was created.
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In the case of Port 2000 Le Havre, not only the economical and functional requirements, but also environmental issues were taken into account. The construction was executed in phases to minimize the ecological effects on the estuary. Compensation measures were taken to mitigate environmental effects or even enhance the ecosystem.
The expansion of a harbour is mainly based on economical issues. The design and construction methods are shaped by functional requirements and cost limitation only.
General Project Description
Title: Port 2000 Le Havre
Location: Le Havre, France
Date: 2001 - 2006 (construction bird island 2004 - 2005)
Initiator: Port Autonome du Havre
Companies: Boskalis, Dredging International, Atlantic Dragage
Costs: 1,1 billion euro (> 46 million on environment) + 218 million euro for bird island
Abstract: To increase container handling capacity a large harbour extension was planned. Because of the ecological value of the Seine estuary, many environmental measures were taken, such as the creation of a bird island on top of an existing sandbank.
Topics: port expansion, environmental compensation, estuary development, impact mitigation, island reclamation, bird habitat, added environmental value.
As the port of Le Havre reached its limits, a major extension was planned. The community, however, raised many questions on environmental and economic issues, which could only be met by introducing flexibility in the project’s design and construction. The main goals were to minimize the ecological impact and to maximize the use of dredged material.
The creation of a bird island was included in the project as environmental compensation. The island would be located in the Seine estuary as a designated bird habitat.
Project Management and Governance
Because the harbour extension could affect the environment, much opposition existed among fishermen, bird watchers, hunters and local farmers. At the same time a dispute between the European Commission and the French government on the designation of environmental protection areas slowed down the process. Many years of negotiation finally led to consensus on a number of compensating measures.
A large new container harbour was created in the estuary of the Seine, including breakwaters and an access channel. Moreover, the project included compensation measures to minimize the environmental impact. These included the creation of mudflats and bird habitat and the re-routing of infrastructure through ecologically less vulnerable areas. Also the design and construction of the port extension were adapted to meet environmental requirements.
In order to add ecological value to the area and to increase the total area of bird habitat, a bird island suitable for sea birds was projected in the Seine estuary. It was shaped to have a minimal effect on the currents.
BwN-dimension: Because the ecological value of the area was recognized, various environmental compensation measures were taken, including the creation of a bird island with dredged material. Moreover, by applying Building with Nature principles, the environment has been included in the design and construction of the port extension.
Planning and Design
The 'wet' part of the project included a maritime access and internal channel of the new port, internal and external protective breakwaters, two beaches and a bird island. A major concern was to what extent the new harbour would influence the flood channel of the Seine estuary. In the design both economic and ecological values were considered. apart from a number of compensating measures, the project was constructed in different phases in order to minimize the environmental impact (see Çonstruction).
The bird island was constructed south of the port extension, on a sandbank called "Banc du Ratier", situated in the middle of the Seine main channel. Available knowledge about bird behaviour within the natural environment of the estuary was taken into account in the design. For several reasons the island was given a complex geometric shape: it should be able to resist storms, comply as much as possible with the prevailing currents and provide optimal habitat to different types of sea-birds. The resulting shape is an oval opening to the south. The hard rock revetment provided a different habitat for aquatic life in the otherwise soft-sediment estuary. The island was reclaimed with dredged material from the extension of the approach channel to the port.
The construction of the project has been executed in a number of different phases in order to limit the environmental impact.
First, an inner basin was created, which was designed in a way that the surrounding flood currents where not altered in a mayor way. This basin was used to temporarily store sand and gravel from the newly dredged access channel. The next phase was the creation of the base of the western part of the island. Construction was only under-water, preventing obstruction of the flood currents. This provided time for the estuary system to adapt to the new situation. Finally, the dikes above water were constructed. And the last phase was opening the temporary dike en simultaneously the permanent (inner) dike was closed.
Material dredged from the port channel was used to construct the bird island. After construction of a dike along the future perimeter of the island, hopper dredgers discharged the sand during high-tide, while earth-moving equipment shaped the island during low tide. This method was favoured over the hydraulic transport of dredged material, which in this case would have resulted in higher turbidity. Finally, a rock revetment was placed around the island for protection against wave attack and at the same time as a new substrate.
BwN-dimension: The environmental factor has been of great influence on the construction process. During construction multiple measures were taken to mitigate the environmental impact. Moreover, the creation of underwater basins before closing off the harbour area provided time for the ecosystem to adapt to the new situation. Furthermore, dredged material was used to create environmental value in terms of bird habitat, mudflats and beaches.
Operation and Maintenance
The artificial bird island has been effective in attracting a range of bird species and ornithologists are confident of further progress in the future. Directly after construction of the island (and even during construction) birds started to settle on it and to forage in the shallow waters of the small bay. The evaluation of the environmental restoration and compensation measures in the Seine Estuary is ongoing.
- The port extension was put into use in March 2006, and so were the beaches and the bird island. First observations suggest that the bird island is fulfilling its functions.
- With well thought-out planning and engineering this harbour extension project did not only minimise environmental impact during construction, but even enhanced environmental values while implementing commercial infrastructure.
- By combining available resources and making clever use of the prevailing conditions it is possible to achieve sustainable infrastructure and nature development with limited effort.
- Mink, F., W. Dirks, H. de Vlieger, G. van Raalte, M. and Russell, 2007. Pressure on ports: Evaluating EU habitats legislation. Terra et Aqua 109:pp. 3-10.
- RBW, 2005. Creation of a bird island south of Le Havre port extension. Project Data Sheet.
- VandenBroeck, J., 2006. Port 2000, Le Havre's new container terminal: breakwaters and dredging of the nautical access channel. Terre et Aqua 104:pp. 22-27.
- P. Galichon, L Hamm J Vandenbroeck (2006). The extension of Le Havre Port in the Seine Estuary - Sediment management on a Large Scale Project. PIANC 31st Congress, 14-18 May 2006, Estoril, Lisbon.