Road network

The road network is the system of interconnected roads designed to accommodate wheeled road going vehicles and pedestrian traffic.

Description

The road network consists of a system of interconnected paved carriageways which are designed to carry buses, cars and goods vehicles; the road network generally forms the most basic level of transport infrastructure within urban areas, and will link with all other areas, both within and beyond the boundaries of the urban area.

A road network can be divided into parts such as:

• intersections
  • controlled or uncontrolled intersections
  • roundabouts
• urban roads
• rural roads
• motorways
• bicycle lanes
• footpaths and pedestrian areas
• pedestrian crossings

Furthermore, several road-side systems (or Intelligent Transportation Systems, ITS) and monitoring systems are used to control the traffic, such as

• intersection control with traffic lights
• Variable Message Signs (VMS)
• Dynamic Road Information Panels (DRIPs)
• loop detectors

Functions

Social

The road network facilitates the movement of people allowing for social interaction.

Economic

By connecting geographic locations, road networks facilitate the transport and movement of people, goods, and services, creating economic impact (i.e. jobs and income). Road networks not only reduce travel time and travel costs (primary economic effects), but also improve the functioning of the local markets due to an increase in scale and size of local markets (e.g. the local labour market or retail business). These effects can be measured with the help of economic tools.

Although road networks are hardly affected by security threats (crime, terrorism), it can happen that roads get blocked due to e.g. riots, bomb explosions, traffic flow management, etc. The economic impact of these kind of threats can be significant, especially in indirect terms since roads facilitate economic activities. Security measures can prevent these negative economic effects, for example, by ensuring there are alternatives routes for traffic (traffic flow management).

Mobility

The road network facilitates movement from one area to another, and has an important role to play in the urban environment.

Safety

Safety of road users is typically focused on road safety (prevention of accidents through speed control, seatbelt enforcement, etc).

Security Issues

The use of the road network is regarded as being safe, with the main threats to security coming from the possibility of vehicle theft or vandalism.

• Terrorist threats? (JP)
• Road blocks by rioters? (JP)

Measures

A highly visible police presence can limit the threats to safety and security.

• traffic flow management (JP)?