Highways Agency

Thames Valley Journey Time: Reliability and Quality

Safe Roads

The following make travelling on motorways unsafe:

• Excessive speed
• Travelling too close
• Unforeseen incidents ahead
• Poor lane discipline

What can be done?

Speed Management

Speed management can help improve safety and reduce the number of incidents.

Headway Management

Managing the gaps between vehicles, for example by chevron markings, can give drivers more time to react and control braking, therefore avoiding collisions, helping to alleviate congestion and reducing ‘shockwaves’ caused by braking traffic.

Reliable Journeys

The following can cause delays and make journeys unreliable:

• Accidents and incidents causing a build up of queuing traffic
• "Shockwaves" – vehicles braking harshly behind slower vehicles, before moving on at a slower speed
• Congestion due to major events or roadworks

What can be done?

• Delays might be reduced and journeys might be made more reliable by:
• Controlled use of the hard shoulder at the time of incident related congestion
• Controlling speeds and slowing traffic down gradually ahead of queues
• Reducing distraction – higher central barriers reduce "rubber necking" congestion on the carriageway opposite an incident

Access Management

Traffic signals at entry to the motorway can:

• Control traffic flow on to motorway
• Reduce congestion where traffic merges from slip roads
• Improve traffic flow through junctions

Incident Recovery

Highway Agency Traffic Officers now patrol the network, and Incident Support Units are  provided.

Currently Traffic Officers, Incident Support Units, the emergency services and recovery vehicles are delayed because some bridge columns block the hard shoulder.

A continuous hard shoulder, together with controlled motorway, would enable the hard shoulder to be used as a running lane during incidents if one of the other lanes was closed.

With a continuous hard shoulder, emergency services and recovery vehicles can get to any incident without difficulty. A continuous hard shoulder could be achieved through:

• Replacing bridges that obstruct the hard shoulder with new designs
• Narrowing lanes and the central reserve to allow for a continuous hard shoulder
• Constructing the hard shoulder behind existing bridge columns

Informed Travellers

Information enables better decisions to be made when planning a journey.

Information can be provided:

• Before the journey
• Whilst travelling

Before the Journey

Information can be provided as follows:

Web based planning services can include expected journey times and alternative travel options (for example, Transport Direct)

• A mobile phone message service can give information on expected travel times
• Information can be updated when roadworks or other events take place

Whilst Travelling

Real-time updates can be linked to:

• Variable message signs at the roadside
• In-car navigation systems
• Mobile phones
• Car radio-based systems
• Displays at service areas

Priority Lanes

Lanes can be designated for use by particular types of vehicles, giving them priority over others.

The purpose of this is to encourage the use of these vehicles and to encourage car sharing, thereby reducing the total number of vehicles on the road.

Examples

Priority could be designated for use by:

• Buses, coaches, taxis and motorcycles
• High Occupancy Vehicles (HOV) – vehicles with more than one occupant
• Vehicles with lower emissions of pollutants and greenhouse gases
• Officials and competitors at the time of the 2012 London Olympic Games
• A combination of some of the above

Environment

The Highways Agency is committed to respecting the environment.

With any improvement works, however, there are a wide range of potential environmental implications. These include:

• Air Quality
• Road Surfacing
• Noise Barriers
• Landscape

Air Quality

Air pollution from vehicles can be reduced near residential areas by controlling the speed of vehicles so that standing traffic, and rapid acceleration and deceleration, are minimised.

Road Surfacing

New types of road surface materials can help reduce noise from travelling vehicles.

Noise Barriers

Noise barriers are often fences, sometimes with noise absorbing characteristics, which redirect noise from road traffic, and can help reduce noise pollution in residential areas.