Factfile – Skandia Gateway Project

In just 10 years the average container vessel has become 10 times larger. The limited depth in the fairway means that the largest vessels are currently unable to call at the Port of Gothenburg when fully loaded.

According to a study produced by the Swedish Transport Administration, the fairway needs to be deepened by around four metres if the draught is to be sufficient. The area that requires deepening is almost 5 kilometres long. In total, dredge spoils equivalent to the volume of 20 Globe Arenas will need to be excavated. A vital part of this initiative is the deepening and reinforcement of the quays to allow vessels with a large draught to load and discharge simultaneously and sustainably in the future.

Gothenburg Port Authority is also involved in discussions with contractors

Deepening the fairway will require extensive reinforcement of the existing quays at our container terminal.

The Gothenburg Port Authority is involved in discussions with contractors that may be interested at a later stage in submitting tenders as part of the upcoming procurement process linked to our quay reinforcement programme. Contractors that are interested in taking part in discussions are invited to notify the Gothenburg Port Authority by emailing Jan Andersson, Senior Technical Advisor and Project Manager, at jan.andersson@portgot.se

FAQ Dredging of the fairway and docks, Port of Gothenburg

Why does the fairway need to be deepened?
Answer: To maintain the competitiveness of Sweden and the Port of Gothenburg on the international freight market, and to ensure they remain competitive in the future, the fairway and the docks need to be adapted to the global container fleet. If the fairway is not deepened, the Port of Gothenburg would in the future not be able to receive the largest vessels. If that were to happen, Swedish export and import companies would no longer have direct access to the world via a major international port. Shipping is by far the most sustainable means of transporting large volumes of freight over long distances. Without access to a major port with direct links to the continent, Swedish industry would be faced with additional costs and longer lead times. It would also result in a larger carbon footprint over which it would have very little control.

What volume of dredge spoils are we looking at?
Answer: A total of 13.5 million cubic metres of clay will be excavated. Of this, 285,000 cubic metres of contaminated clay will come from docks where the former shipyards emitted a number of environmentally hazardous substances, including mercury and tributyltin. Most of the dredge spoils are thus clean and made up of preindustrial glacial clay deposited during the ice age.

Why can you not deposit 285,000 cubic metres of contaminated material on land instead of in the sea?
Answer: During the work leading up to our permit application we conducted several inquiries and investigations dealing with the various alternatives for handling excavated spoils.  It is based on this work that we feel that the proposed solution – deposition in the sea – is the best alternative. Problems and risks associated with landfill would include the use of large areas of land, the need to drain the material, and the need to take care of the resulting water. Transporting the spoils would also require almost 14,000 truck movements. In addition, there is the problem of finding suitable landfill locations for the spoils and the risk that natural sea salt in the spoils could prove ecologically hazardous if it were to rise to the surface and leach out into the natural environment. By using large barges instead of trucks to move the spoils, we would not only reduce the number of transport movements, and thus unnecessary carbon emissions, but also the reloading frequency with less risk of spillage.

Are you not simply shifting the problem when you excavate polluted dredge spoils from the docks and deposit them out at Vinga?
Answer: No, quite the opposite. Both the seabed and the habitat for flora and fauna will be improved once dredging has been completed. This is the case out at Vinga and in the port, where the materials in question are at present totally exposed at the mouth of the Göta Älv River and are being washed out to sea. Our investigations show that by depositing the polluted dredge spoils in deep repositories and sealing them with a 10-metre layer of clean dredging spoils, they will no longer pose a threat to the environment.

Why just off Vinga?
Answer: The location just off Vinga was chosen following a careful examination of the seabed as it offered accumulating conditions and there are no currents that could cause the spoils to move. 

You say that the dredge spoils will remain still in the deep repositories. Have you any control over this?
Answer: Yes. We intend to draw up a programme of checks to manage and monitor the site over several years. The control programme will be approved by the regulatory authority.

When you release the polluted spoils into the sea off Vinga, is there not a risk that they will then spread?
Answer: The dredge spoils will be released 4-5 metres below the water surface, falling directly onto the seabed, and will not spread beyond the designated area. It is inevitable that there will be spillage when the spoils are released, but this has been carefully modelled and the assessment is that it will not have any negative implications for the marine environment.

When you dredge the water becomes turbid. Will this not affect marine life?
Answer: The turbidity that results from dredging has been modelled. Coupled with our experience from previous projects we know that the resulting turbidity will have minimal impact on marine life, both now and in the future.

How sure are you that this will work?
Answer: We are quite sure as we have done it before. In 2000-2004 the Swedish Maritime Administration and the Gothenburg Port Authority ran the Safer Fairway dredging project in Gothenburg with the same dredging volumes that we have now. The approach we have opted for has already been tried, tested, and approved. Follow-up investigations have shown that there has been no permanent damage to the environment or marine life.

I have more questions. Who can provide the answers?

Answer: You are more than welcome to contact: 
Jenny Röström, Project Manager for Skandia Gateway at the Swedish Maritime Administration. 
She can be reached at: 
jenny.rostrom@sjofartsverket.se,
mobile 0707-24 57 76 or

Jan Andersson Sub-Project Manager for Skandia Gateway at the Gothenburg Port Authority. 
He can be reached at: 
jan.andersson@portgot.se,
phone 031-368 75 27.