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Roads: Motorway Gantries

Volume 694: debated on Tuesday 24 July 2007

asked Her Majesty's Government:

When the motorway gantry traffic information system messages were last evaluated for accuracy and timeliness. [HL4903]

The Highways Agency has around 2,400 variable message signs (VMS), located primarily on the busier parts of the strategic road network and at major intersections. They are set by automated systems, the motorway incident detection and automatic signalling (MIDAS) system or by operators working from control centres. The National Traffic Control Centre (NTCC) monitors this network and sets “strategic” or longer-distance messages, such as diversion information. The seven regional control centres (RCCs) monitor the network at a more local level and set “tactical” or local messages. Where installed, MIDAS detects slow-moving or stationary traffic (from loops in the road) and sets safety messages on VMS.

Supervisory staff working in these control centres assess the accuracy and timeliness of signs in real time. In addition, the performance of the Traffic Officer Service/RCCs and the performance of the NTCC are monitored monthly through performance indicators. In addition, the agency, through its road users’ satisfaction survey, seeks customers’ views on the accuracy of speed reduction and “conditions ahead” information, as well as whether the information has improved over the past 12 months.