Measure type: Directing traffic flows

Directing traffic flows is a traffic management measure of directing the traffic in a preferred way, for example reducing the opportunities for a criminal to approach a suitable target by physically separating the flows of traffic.

Description

Directing traffic flows is a traffic management measure of directing the traffic in a preferred way. Usually this is done from a traffic management perspective to improve throughput of a road network. For example, when a certain route is congested, the traffic can be guided to an alternative route with a dynamic route information panel (DRIP). The measure is also applied to increase safety, such as for instance to prevent flows of traffic from colliding, manage crowds or to support evacuation management in case of emergencies.

Another application of directing traffic flows is to increase security. In this case, the measure is usually intended to separate potential offenders from locations or circumstances where they might do harm. Examples include building barriers for vehicles, to ensure a stand-off zone as a protection against car bombs, to provide safe transportation for the public across high-risk areas or to separate pedestrians from motorcycles to prevent snatch theft.

A traffic flow measure can be directed at all traffic, or only certain modes.

Effectiveness

Economic effectiveness

Directing traffic flows does not only reduce the potential impact of security threats, but also requires time and money by private agents, companies/developers and the public authorities, exacting economic costs. Together, the benefits and costs are referred to as economic impact of security measures. The costs of traffic flow management measures contain the relatively straightforward direct expenditures on capital equipment and operational costs (both temporary and permanent), and in addition generate various types of secondary effects.

In general traffic flows that are being managed will be more robust than in the opposite case. One should bear in mind though that at the same time traffic will be limited as well. This as a result of this traffic flow directing. Traffic rules such as speed limits, for example, aim to improve safety and the robustness of the road network, but at the same time increase travel time for road users Since they cannot drive as fast as wished for in all cases). Indirectly, this limited accessibility could lead to negative economic effects as a result of the less efficient transportation of goods, skills and persons. These negative impacts will reduce the functioning of the markets in the local economy, reduce the functioning of labour markets and attribute to less scale and agglomeration advances due to a decreased market size.

Whether the costs are making sense from an economic point of view, depends on many factors, and can be answered by two distinct sets of questions:

1. Are the envisioned measures cost effective from a socio-economic point of view, or are there better alternatives?
2. Which specific agents (individuals, companies, sectors, authorities) are affected by the specific measures, and to which extend? How do the envisioned measures adjust the behaviour of these agents, and of course the behaviour of criminals/terrorists?

Economic tools can help the decision makers to answer these questions and to prevent wasteful expenditures on security (of course in collaboration with insights from criminology, sociology, etc.).