An £8m revamp of Junction 16 of the M4 – which could severely increase congestion on feeder roads – may be pushed ahead without any public consultation, a rural lobby group fears.
Plans to overhaul the busy junction, to smooth the flow of traffic, have been in negotiation since 1999, but local councillors have been joined by the Campaign For The Protection Of Rural England in calling for full scrutiny of the latest proposals.
The Highways Agency plans to widen the Swindon Road and Hay Lane junctions, widen slip roads to four lanes, and create a new right turn to Swindon at Hay Lane.
Wiltshire Council has said the plan should be looked at in isolation and issues arising from nearby housing estates should be addressed by individual developers.
But Charmian Spickernell, of the CPRE, said the public should have the chance to comment on proposals.
She said: “Consultants in the past have said that if you increase the traffic flow around that junction it will cause severe congestion on the feeder roads, particularly around Wootton Bassett and Wroughton.
“There are some real safety issues around Junction 16. Transport consultants said the lanes are so narrow there would not be room for lorries to manoeuvre around bends.
“Under the recent proposals people would be coming quite fast off the motorway, with others coming on their offside through traffic lights.”
A council spokesman said: “The changes will not have negative effects on the environment, so the development does not require an Environmental Impact Assessment.”