Limiting Nuisance for Traffic during the Refurbishment of the Heinenoord Tunnel in The Netherlands:In Search of Resilience Possibilities

The Heinenoord Tunnel in The Netherlands connects the Hoeksche Waard Island with the city of Rotterdam.The tunnel is 614 m long,consists of two unidirectional tubes(3 lanes each)and has an average daily traffic load of 92,100 vehicles.The tunnel was opened for traffic in 1969.The structure is basically still sound,but a full refurbishment of the installations and systems is required,because they are end of life.A long closure of the tunnel(or even one tube)is not possible,because alternative routes are scarce and require significant extra travel time,not suitable for the high traffic load.Thus,various scenarios were considered to assure the accessibility of the Hoeksche Waard during the works,scheduled for 2023-2024.Multi-criteria analyses were performed for each scenario,taking into account the total project cost,societal cost(due to extra travel time)and the total required time span for the works.Refurbishment through“parallel assembly”proved to be optimal.This concept means that the new installations and systems are installed next to the current ones,that will remain in service until the end phase of the refurbishment.The existing installations and systems are only dismantled after integral testing has shown that the completed new ones work properly.This approach allows most of the works to be carried out during a series of night and weekend closures of just one tube.This limits nuisance,because one driving direction is always left undisturbed,while the closure for the other driving direction takes place in low-traffic periods.This paper describes the applied method to select the optimal refurbishment approach,as well as the(partly unconventional)measures that are implemented to enhance the resilience of the tunnel system to assure as much availability for traffic as possible,also during future maintenance works.