Vistula Spit, making waves by breaking waves

An innovative technology to build breakwaters

In Poland, BESIX is contributing to the construction of a new shipping channel in the Gulf of Gdansk. This is a strategic investment for the country, as it will facilitate maritime traffic and give a boost to Elblag’s port activities, local employment and the economy. In addition to the canal, the project also includes the typical marine engineering works in which the Group has excelled for more than 60 years. A project of experience meets innovation, in which breakwaters are being built using a new technology, the XblocPlus.

10,000 blocks

Under a beautiful layer of snow in January, yet still recognisable: the striking shape of the no fewer than 100 first XblocPlus blocks. There will be 10,000 blocks in total, or 21,000 m³ of unreinforced concrete. The concrete blocks will reinforce the structure of the eastern and western breakwaters, which are 900m and 300m long respectively.

This improved version of the globally used XBloc is making its international debut in Poland. Why? The advantages make a strong case.

Better and stronger

Building breakwaters in the Middle East and Australia taught us that the material used is the basis of everything. The structures must not only withstand the typical perils of the sea, but they must also be easy to place and fit into the economic and sustainable requirements of the project. This is how the Vistula Spit team came up with the XblocPlus, elements developed by Delta Marine Consultants in 2018. It primarily distinguishes itself from its predecessor by the hole in the middle. This has the function of reducing water pressure and increasing stability, which makes the structure more resistant to climate change.

Faster and safer

What makes this type of breakwater even more different, however, is the way it is installed. Unlike other breakwaters, the XblocPlus is placed in a regular and orderly way. The site team therefore significantly gains in accuracy, time (up to more than 100 blocks per day!) and safety. There is only one worker needed, behind the controls of a 'Long Reach' excavator. He works from land and not from the water, to be less dependent on weather conditions when building these breakwaters.

More sustainable

Moreover, the new shape is also a step forward economically. Less material is required to make each element and 50% fewer blocks are needed in total to build the same number of km of breakwaters. At Vistula Spit, they range in weight from 2.34 to 9.6 tonnes each and come in three different sizes (1m3, 3m3 and 4m3), depending on where they are placed. For example, the rounded ends of the breakwaters require a different type of Xbloc block (3m3 and 5m3).

All this also contributes to a more sustainable project. Think of a lower CO2 footprint as a result of material reduction and the reuse of the blocks. Marine life also benefits from this. BESIX and Grupa NDI are both known for their expertise in building infrastructure that meets the strictest environmental standards, and applying this technology fits perfectly in their domain of expertise. Marine life can thrive on the elements which, thanks to their special surface, are the ideal habitat for the fauna and flora of the area.

Currently, the two breakwaters of Vistula Spit are under construction. Despite the winter period, the works are progressing quickly. The first one should be ready by the end of the year.