dws-grontmij-dike-design-wantum-770pxpxWater board Noorderzijlvest has contracted Dutch-based consultancy firm Grontmij to make a preliminary design and a contract for a 12 km sea dike improvement between Eemshaven and Delfzijl, on the north coast of the Netherlands.

The flood defence project is part of a nationwide programme to reinforce dikes to withstand heavier wave loads. The authorities decided to accelerate this particular project because of increasing frequency of earthquakes caused by local gas extraction activities.

Specific for this section, the sea dike also has to be made earthquake proof which is very unusual for flood defences in the Netherlands.

The preliminary design and contract have to be ready by November 2015.

dws-grontmij-sea-dike-delfzijl-eemshaven-aerial-350px The 12 km long sea dike section that has to be enforced.

Multi-criteria design
The design takes into account seismic activities and opportunities for other regional developments such as a city beach in Delfzijl, various recreational facilities at Eemshaven, and nature development.

Besides making a design, Grontmij prepares all procedures and permits and drafts a contract which constructors can register for.

Dike improvement speeded up
Ate Wijnstra, project leader water board Noorderzijlvest: "We take responsibility for water- and earthquake safety for our residents and have the ambition to accelerate the work on this dike improvement. Because Grontmij has in-house specialists in both seawalls and earthquakes, they provide exactly what we need to translate this task into a good design and a contract in a short period of time."

dws-grontmij-dike-design-delfzijl-350pxStorms damaged the asphalt coating on the sea dikes and water board Noorderzijlvest has to make repairs earlier than usual.

Experience in earthquake prone areas
Jana Steenbergen-Kajabová, business developer Protecting Deltas at Grontmij: "Our company has over 100 years of experience in protecting the Netherlands and other delta areas from flooding. We were among others active in the rebuilding of the Dutch province of Zeeland after the floods in 1953, and now in Jakarta."

Steenbergen-Kajabová: "Besides, we also have more than fifteen years of experience in the inventory of risks and building in earthquake prone areas such as China and Turkey, but also more recently in the Netherlands. We like to use this knowledge and experience to achieve the ambitions of the water board Noorderzijlvest."

EU-code for earthquake resistance
"The insights regarding the construction of dikes in earthquake-prone areas, is still in development in the Netherlands", adds Steenbergen-Kajabová. She expects that Eurocode 8 for the design of structures for earthquake resistance, can provide a good guidance. "We designed the flood defenses along the near-by Ems Canal. This experience will certainly help us to make a good earthquake-proof design for this dike".

This news item is based on a press release originally published on the website of Grontmij (in Dutch only)

More information
De Bilt, the Netherlands
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