Tuesday, August 4, 1998 Published at 07:52 GMT 08:52 UK
Road capacity 'could be increased four-fold'
Overhead gantries can be used to control traffic flow
The government agency that manages motorways and trunk roads says a four-fold increase in traffic capacity could be achieved by using new technology.
According to the agency new methods of monitoring traffic flows, controlling vehicle speeds and communicating with drivers could make the road network more efficient.
Trials of the new technology should begin on the M4 and the M25 between Heathrow and Gatwick airports later this year.
The Highways Agency also plans to introduce more bus and lorry lanes on motorways and extend the use of variable speed limits to smooth out rush hour traffic.
On the vehicles' dashboard, messages will be received from roadside beacons about possible hazards ahead and, where necessary, drivers will be warned to slow down.
Such measures could eventually lead to existing roads carrying up to four times as much traffic.
"So all these small changes that will occur over the next few years will have a fairly big impact in a 10 to 15 year time frame."
The M25 already has automatic equipment that detects hold-ups and then uses signs on overhead gantries to warn drivers of the delays ahead.
The Highway's Agency hopes to develop this technology further.
Three regional traffic control centres will also be built to monitor congestion and keep motorists informed of potential delays.