Reconstruction of Storm Surge Barrier Billwerder Bucht, Hamburg

Aerial view: Barrier before reconstruction Client: Free and Hanseatic City of Hamburg Construction Costs: approx. 30 mill. € Services: Conceptual, pre-engineering and detailed engineering, tendering, site supervision Period: 1996 - 2003 Cooperation: Prof. Dr. Lackner & Partner GmbH

As result of a new policy of storm surge protection of the City and the Port of Hamburg (as result of increased extreme water levels) the protection level of all existing structures along the almost 100 km long storm surge protection line have to be raised. The barrier Billwerder Bucht has been constructed in 1966 and had to be modified from a protection level NN +7.00 m to NN +8.20 m.

In addition the reconstruction should also provide the required second defence line.
The barrier is about 150 m long and includes 4 openings.

During the conceptual stage several options for storm surge protection have been compared:

• complete demolition and reconstruction
  
• construction of locks
  
• flood protection measures in the entire bay behind the barrier

In addition several technical options for the closure devices have been analysed.

A reconstruction with integration of existing facilities has been selected. The existing barrier is constructed on the upstream side of the existing barrier as an structurally entire independent building. The engineering design included:

• foundation
  
• gate piers
  
• gates
  
• hydraulic system
  
• buildings.

The coordination of various contractors (management of interfaces) was essential during construction supervision.

During construction shipping and motor traffic had to be allowed.