Theory of evolution

How does a National Traffic Management System in Sweden deal with life-threatening incidents on its region’s roads? Trevor Platt has the details.

The National Traffic management System delivers an integrated service for the whole of the Swedish road network, managing at local, regional and national levels, through four regional and coordinated management centres. It provides a comprehensive decision support facility, bringing information from multiple systems together into a single platform and tool, automating many services to enable operators to focus on critical decision making. It communicates with multiple systems and stakeholders, including highway operators and maintainers, public transport service providers, the emergency services, the media and third-party information system suppliers. This multi-layered and expert system has evolved over many years to become one of the world’s most advanced systems.

Pieces of the jigsaw

There are over 50 subsystems today and their connected roadside devices total some 10,000 in number and include over 100 different equipment types, each with particular operational requirements.

They include SCADA systems for the control of tunnels, weather and climate control, CCTV and road condition cameras, traffic and radar incident detection, urban traffic signalling, lighting, variable message signing and lane control signalling, radio and RDS TMC, road assistance and maintenance vehicles, emergency telephones, the list goes on.

The process of subsystem integration has been simplified through the use of an industry standard IP network, using standard and bespoke interfaces – e.g. Microsoft.NET remoting, web services, DCOM, XML, ASN.1 and ODBC.

By integrating these subsystems into a single platform it is now possible to minimise the number of items on the control desk to a single workstation, consisting of one virtual screen (comprising multiple monitors), one mouse and one keyboard, to optimise operator performance. Creating a single view of the network enables an operator to effectively manage major incidents and the system provides them with high levels of decision support, taking many routine decisions automatically, guiding through a process of pre-defined action plans running in series and multiple parallel work flows, prompting the operator to take certain actions at certain times and when conditions occur, all allowing the operator the time and ability to take the critical decisions and actions when they are needed.

The diagram below shows the type of information that feeds into the Traffic Management Centre (TMC) and what information comes out of the TMC and where it appears.

Theory of evolution diagram
INCIDENT ONE – 6 May 2013: major accident on Sweden’s busiest road

There was a major accident between a lorry and a car at 7.00 am on Sweden’s busiest road, the E4/E20 at Essingeleden. All southbound lanes were closed directly after the collision. After 30 minutes one lane (out of four) was opened and after 1 hour and 45 minutes all four lanes were opened. Massive queues occurred in both directions on the E4 and all roads towards Stockholm from the north were congested throughout the morning. The Södra Länken tunnel closed all entries for over 1 hour for safety reasons. Disruption on southbound routes lasted for 12 hours.

This major incident was effectively managed by only one operator at the TMC. NTS analysed the problem defined in the system and used its expert system to propose the best action plan to respond to the accident, helping the operator to take the most appropriate actions in a logical and agreed process to effectively resolve and close the incident. NTS presented all alert and camera information to the operator when the accident happened and proposed the best camera to verify the incident. The system helped the operator to distribute streaming video, information and alerts to the TCC co-operating parties including the police, fire rescue, emergency assistance vehicles, the media, along with senior management at Trafikverket. NTS coordinated response planning which included changing the Stockholm city traffic signal timing plans and managing traffic on the motorways and strategic roads through lane signals and variable message signs. Within the control room, NTS managed the video wall to display the right information to stakeholders including television and radio operators. NTS issued traffic information through the Trafikverket website and via SMS, fax and email. They were kept updated with the latest news throughout the entire incident.

INCIDENT TWO – 3 March 2014: major tunnel fire

  • A vehicle caught fire in the Södra Länken tunnel.
  • One operator was able to safely close the tunnel in just over 3 minutes from verification.
  • The Operator received a phone call from a motorist in the tunnel as well as a number of system alerts, the operator created an incident report, verified the vehicle fire using CCTV and executed an action plan.
  • NTS implemented 280 specific commands, closing tunnel entrances and sent commands to 11 different systems (VMS, sprinkler systems, fire ventilation, barriers to close tunnel, radio messages, SMS and traffic information and emergency services notified).
  • The fire was quickly dealt with to prevent damage to the tunnel and no persons were injured, and to minimise the impact of tunnel closure on the surrounding network.
  • The response to such an incident could not have been dealt with as swiftly without an integrated system.

Trevor Platt is Sales and Marketing Manager at Nicander