A Road with History
The initial plans for completing the construction of the A4 motorway were already available in the fifties. Following many objections concerning the impact on the area, work was halted. Today, almost 60 years later, the 7-kilometre-long ‘forgotten’ motorway was completed by the building combination A4ALL (Heijmans, VolkerWessels & Boskalis). This has significantly improved accessibility between Rotterdam and The Hague.
Don’t Hear, See or Smell
Reduced noise pollution and optimal integration into the environment are the demands that were made on the project. The solution? The next section: coming from Delft, a 2.6-km stretch of road gradually descends below ground level, followed by a 1.4-km stretch that runs entirely below ground level. In the region of Schiedam and Vlaardingen, there is a 2-km land tunnel connecting to Kethelplein.
A sports park with trees and cycle paths will be built on top of the land tunnel and the tunnel openings will be fitted with soundproofing. In emergency situations, traffic will be guided to escape routes in the middle lane of the tunnel by lighting and sound.
Temporary Bridges & Weekend Work
Various constructions have been thought of to minimize disruption to residents and traffic. An underpass was installed in the weekend and eight temporary bridges were placed which are used by work traffic to avoid disrupting the current road network.
Largest Eco Aqueduct
An eco aqueduct has been constructed across the motorway, providing an uninterrupted ecological structure. Spanning 100 metres wide, it is the largest aqueduct in the Netherlands. In addition to various animal species, pedestrians and canoeists can cross the eco aqueduct using the hiking and canoe links.
The polder construction was applied for the building of the road below ground level and for the gradual descent. The cement-bentonite walls dug into the ground, together with the natural water-resistant layers, form a container. This ‘polder in polder’ construction enables permanent groundwater level control and makes the construction of a floor unnecessary.