Large cable project in a unique environment

The Royal National City Park is located between Ulriksdal in northern Stockholm and Fjäderholmarna in southern Stockholm. The park is a twenty-seven square kilometer area. In this unique environment, Skanska and Ellevio have carried out a cable project. An existing aerial line was replaced by an underground line. The purpose was to secure large parts of Stockholm's future electricity supply.

Sensitive environment dictated the work

The Royal National City Park consists of oak forests, parks, lakes and castles that Stockholm citizens and visitors can enjoy all year round. The environment is very sensitive and the work could therefore only be carried out between May and October. This meant extra careful planning where obstacles and challenges had to be identified before the work began. Our planning helped us to be efficient on the worksite.

Before the project began, there were major geotechnical challenges that needed to be resolved. The project was divided into two phases between 2017 and 2018. The time between phases one and two was used to plan for the next phase.

Construction contract with a focus on climate and safety

The construction contract made sure both Skanska and Ellevio had a strong focus on climate and safety. To ensure decision-making was quick, Ellevio had its own office at the establishment. This way, Ellevio gained insight into the daily work and was familiar with the details. As the project progressed, challenges related to earthworks and geotechnics were discovered. Thanks to Ellevio’s presence at the establishment, quick decisions could be made and helped us keep the timetable.

Cable laying in the middle of a relay race

Early in the project, we discovered that the cable laying would go straight through one of Sweden's largest relay races – Convinistafetten. To avoid the problem, an alternative route for the race was proposed to ensure the runners’ safety.

Sustainable solutions were chosen

We chose sustainable solutions to the greatest extent possible in the project. Among other things, green asphalt was used on a road and we took measures to minimize mass transportation. The Royal National City Park became one of the first projects to use Coredination, a mass and transport logistics tool where the system optimizes the utilization of transport and mass handling.

Safety in focus

During the course of the project, safety was Skanska's and Ellevio's highest priority, which clearly permeated the entire project. Everyone focused on the working environment – from client and project management to skilled workers and subcontractors. A proof of this is that the Royal National City Park project was awarded Ellevio's safety award in 2018.

About the project

• In total, approximately 46,000 meters of cable were laid
• The cable measured 13 centimeters in diameter
• The cable weighed 17 kilograms per meter