FUNDING for major new transport investment - including an overhaul of junction 16 of the M4 - will be put to the Swindon and Wiltshire Economic Partnership this month.

After years of increasing congestion at the roundabout, plans have been floating since the turn of the century to widen feeder roads, and estimated costs have been slashed from an initial £11.54m to £7.2m.

It is thought the scheme would pave the way for an access tunnel under the M4 to Wichelstowe, which was originally proposed in 2002.

However, campaigners have raised major concerns about the viability of the plans, after a public consultation was limited to Swindon, with various consultants pointing out the potential for severe congestion in Royal Wootton Bassett, and safety issues on the junction itself.

The plans propose to introduce a right-turn for Swindon Road traffic turning on to Hay Lane and a new, signal-controlled junction for traffic joining Hay Lane from junction 16.

The M4 slip roads would be widened to four lanes, and capacity on the circulation carriageway on the Great Western Way approach would be increased.

Work will also include changes to road signs and markings and alterations to the surface water drainage systems.

Also included in this year’s funding bids is a £4.5m improvement scheme for J15.

Charmian Spickernell, the vice-chairman of the Campaign To Protect Rural England, has been calling for greater scrutiny of the plans and said the system itself lacks accountability.

“Instead of funding for transport coming through the local councils, it is now coming through partnerships of unelected business people together with the leaders of the councils and two cabinet members from each council,” she said.

“It appears that some decisions are announced without debate in the local councils and without proper public consultation despite Government insistence on the need to engage with stakeholders and the general public.

“In particular, the proposed improvements to M4 junction 16, raise issues of safety at the junction and severe congestion on local roads.

“The transport corridor should have been assessed to seek the best solution, rather than progressing an isolated road scheme.

“There appears to be no evidence of the separation between promoter and decision maker that the Department of Transport asks for.

“It is questioned whether the scheme is best value for money.”

From this month, the Department of Transport is devolving funding for major transport in Wiltshire to the SWLEP.

A total of £129.3m has been secured from the government’s Local Growth Fund to support economic growth, with £12m confirmed for 2015-16 and £50.1m for 2016/17 to 2021.