The motorway network (HWN) plays a crucial role in accommodating traffic flows on the Dutch road network. In this study, an alternative network concept is elaborated. The main feature of this concept lies in a partial but coherent upgrading of the regional road network. The result is a second coherent road network on the regional level: the OWN+ network. This second network is separate but complementary to the motorway network. To quantify the impacts of the suggested approach, the concept was applied to the network of the northern part of the Zuidvleugel. The model calculations were performed for three network configurations: the present network, an upgraded regional network (OWN+), and an upgraded motorway network (adding one lane to each motorway, HWN+ ). These three variants were compared using a cost-benefit analysis. The main results of the model calculations show the following: Upgrading the regional network generates a positive impact on the overall accessibility in the area. Reliability, capacity and accessibility of the transport system are significantly improved. Upgrading the motorway networks generates less positive results in this respect; Applying safe design standards to the upgraded network generates a significant improvement in overall traffic safety; The low maximum speed (70 km/h) allowed on these upgraded roads influences positively traffic safety, restricts the growth in commuter traffic, and acts as an impediment to the use of the regional network by long distance traffic; and upgrading the regional road network creates a clearer hierarchy in the various network junctions. Given that regional government is primarily responsible for the realisation of the OWN+ network, it will be necessary to investigate how the necessary expertise can be upgraded.
Abstract