A9 Gaasperdammerweg

Holendrecht-Diemen
2015-2022
DBFM contract
Ballast Nedam Infra Projects

The A9 Gaasperdammerweg project is an example of going off the beaten track. As part of the IXAS consortium, Ballast Nedam contributed to the Schiphol-Amsterdam-Almere road extension for our client Rijkswaterstaat. The contract included the design, building, maintenance until 2038 and financing. The A9 Gaasperdammerweg project included constructing the longest land tunnel in the Netherlands and creating a park on the tunnel's roof. The project's main goal was to improve the accessibility of the northern Randstad region and the quality of life in Amsterdam Zuidoost.

5,246 solar panels
3 kilometre land tunnel
15 kilometre light coloured asphalt

National Tunnel Standard

Our integral responsibility within the project encouraged us to come up with creative solutions. The motorway was widened to have five lanes in each direction and an alternating lane, and we have built the Gaasperdammertunnel, the longest land tunnel in the Netherlands. The tunnel spans 3 kilometres of the route and includes on and off-ramps. It is the first tunnel that was built following the National Tunnel Standards in the Netherlands and is demonstrably safe and reliable. In addition, the tunnel now ensures a better traffic flow, cleaner air and less traffic noise in the surrounding residential areas.

An autonomous tunnel

The project is a digital piece of art. About fifty technical systems in the tunnel are designed to monitor and interpret tens of thousands of signals to make proper and safe traffic decisions. However, this tunnel’s special feature is that it can behave autonomously. In some cases, it can execute predefined decisions based on signals, which support the road traffic controller to take speed-limiting measures or even close the tunnel.

A good atmosphere, a good neighbour

Given that 87,000 people live close to the project, we immediately researched how to reduce the impact on the environment as much as possible. This resulted in pile drivers being equipped with noise-reducing sheeting, the use of vibration-free foundation techniques, asphalted construction roads to reduce dust and noise and using the river Gaasp as a transport route. Within IXAS, opportunities to involve residents in the project were also considered. In cooperation with Rijkswaterstaat, we organised weekly guided tours, a pop-up cinema in the tunnel and various open days.