Let’s start with the figures, because those are impressive. Five tunnel tubes, five lanes in each direction and an alternating lane. In and around the tunnel there are, amongst others, 140 ventilators, 5,500 light boxes with led lighting, 360 cameras and 366 emergency cabinets. The tunnel comprises a total of 15,000 different components. In 2017, more than 1,300 people were working on the project.
“Our project is big in every respect and that’s what makes this job so special”, Twan Daverveld says proudly. Since the beginning of 2014, he has been working as an advisor for building combination IXAS, a consortium consisting of Heijmans, Ballast Nedam, Fluor and 3i. “During the preparatory phase, I focused on the design process and the integrated collaboration within the consortium. Throughout the execution, I was responsible for all communication between IXAS and the operational stakeholders, such as the safety officer, tunnel operator and the traffic centre of Rijkswaterstaat (the Dutch Department of Public Works and Water Management).”
Key piece of the puzzle
Construction of the Gaasperdammer tunnel is part of the road expansion Schiphol-Amsterdam-Almere (SAA). This project is key to keep the area between Amsterdam and Almere easily accessible. Twan: “IXAS is responsible for the sub project ‘road expansion A9 Holendrecht – Diemen’, in which the tunnel is de key piece of the puzzle. IXAS was granted the project in September 2014, a year after that we started the construction.”
“The fact that we are building in an urban area, makes it a complex puzzle”, Robin adds. “The tunnel is located exactly at the interface of the Amsterdam neighbourhoods Bijlmermeer and Gaasperdam.” As a project manager Robin is responsible for all the technical installations in and around the tunnel. He has been working for IXAS since 2015. “Space for construction was limited. The building site was located right in the middle of a residential area. And we had agreed with the principal Rijkswaterstaat that we wouldn’t use the main and surrounding road network for construction traffic.”
Luxurious construction road
The first hurdle was making room for the tunnel and construction roads. “The phasing consisted of 3 parts. Various rail and metro viaducts have been extended and a total of fourteen temporary bridges have been installed for crossing cars and bicycles”, Robin continues. “The A9 has been expanded. On the northern side sheet piles have been installed and part of the former A9 has been excavated where the tunnel is currently located. And lastly, the alternating lane has been laid. It was originally built to create extra capacity for the A9. However, due to many complaints by local residents, it ended up being used as a construction road. This way we didn’t have to work nights anymore and we could limit any disturbance.”