It is widely accepted that the South West lacks a major road link between the M3/A303 and the M5. At present drivers of all kinds of vehicles – from private and light goods to HGVs – opt to use the A358 to make this connection. Improving this short section of road will be of great benefit to the whole region by providing a high-quality route at limited environmental cost.

Dualling and trunking the A358 will conform with regional and sub-regional policies and improve east-west traffic movements as well as north-south traffic movements.

A road of the current A358 standard could be expected to cope with 13,600 vehicle journeys a day. At present the A358 carries almost 30,000 vehicles a day. It is operating at more than twice its design capacity. Dualling the A358 will relieve congestion and improve safety.

The plan to upgrade the A358 includes a new access point to and from the M5 just south of the existing Junction 25. This proposal conforms with Regional Planning Guidance from the Government Office for the South West published in September 2001. This guidance (Policy SS14) urges the need for: “investment in transport … including measures to address capacity problems at M5 Junction 25.” Planned improvements to the A358 conform to this requirement.

A number of traffic surveys over recent years reinforce the case for improvements to the A358. In July 2000, for example, a study of heavy goods vehicles travelling east on the A358 through Henlade discovered that by far the largest percentage of these vehicles (29%) had set out from Devon and Cornwall. They had chosen to avoid the section of the A303 between Exeter and Ilminster and to use the M5/A358 instead.

There is also evidence that goods vehicles seeking to access the M5 and to avoid the A303 are now using unsuitable country lanes because of hold-ups on the A358. For example, more than 150 lorries a day use a country lane off the B3151 south of Street to avoid congestion on the A358 (see picture).