Assessing the Environmental Impact of Norway's Largest Dredging Project


Vibeke Riis

Division Director, Environment & Health – Norway/Nordics
T: +47 95 08 00 10

Services we provided

Norway's largest dredging project to date is underway, enabling large 'Panamax' ships of 70,000 deadweight tonnes to enter the port of Fredrikstad by 2015. The Norwegian Coastal Administration (NCA) has asked Ramboll to conduct a comprehensive evaluation of the impact that the work will have on local biodiversity. 

Panamax ships are 33 meters wide, about 225 meters long and require a minimum water depth of 12.5 meters. Consequently, the 'fairway' or entry route to Fredrikstad port must be expanded to a width of 150 meters by removing between 1 and 1.7 million cubic meters of both clean and polluted sediments. The most polluted sediments will be placed in landfill, whilst the less polluted and clean sediments will be stored in a deep water disposal site.

Unique project with multiple dimensions

This is the first time such a large quantity of sediments has been dredged in Norway. Ramboll has to take into account both the provisions set out in the EU Water Framework Directive and the strict requirements in place to protect sensitive natural ecosystems such as the coral reef in nearby Hvaler national park.

Framework agreement with NCA

In its 2010-2013 plan, the NCA has EUR 37 million allocated to the expansion of fairways and ports. The Division of Environment, water and climate, Ramboll's geotechnicians and Akvaplan-niva/NIVA have established a framework agreement for environmental and geotechnical investigations for such initiatives with the NCA.

The Fredrikstad port project was awarded under this agreement and further initiatives for 2012 are currently being assigned.

Ramboll's framework contract with NCA concerns environmental issues, more specifically:

• Environmental impact assessments
• Mapping of topography, sediment conditions and environmental quality
• Design of monitoring programmes
• Monitoring during dredging, dumping and capping
• Particle and pollutant spreading during dredging, dumping and capping and its effect on biodiversity
• Changes in topography and effects hereof on hydrographical and physical conditions.


4245 North Fairfax Drive
Suite 700
Arlington, VA 22203
Tel:+1 703 516 2300
Fax:+1 703 516 2345

Company registration

Company registration

Ramboll USA, Inc.

Other sites

Other sites