Covert monitoring has been taking place in Helston capturing drivers flouting the rules of a new traffic trial.

Major changes to the flow of traffic into and from Penzance Road came into force just over a week ago, which will continue for the next six weeks.

Until July 26 traffic travelling over St John’s Bridge from Cross Street, towards the main road, is no longer able to turn right onto Penzance Road, instead being forced to turn left regardless of the direction the driver wants to go in.

However, some motorists have been spotted ignoring this instruction and instead sat waiting to turn right as a queue of traffic built up behind them – much to the frustration of the other drivers, some of which have even got out their cars to argue the point, while others have blared their horns.

Cars travelling down Sithney Common Hill from the Penzance direction towards Helston are also stopped from turning left onto St John’s Bridge, by a road block.

The aim of the trial run by Cormac, on behalf of Cornwall Council, is to see what effect these changes will have on reducing the number of vehicles passing along Cross Street, where the council said there had been “long running issues” and requests from residents to reduce the volume of traffic.

A spokesperson for Cornwall Council said: "The aim of the trial is to provide a definitive answer regarding the effectiveness of any adjustments to the traffic arrangements at the junction. "The trial has been in place for one week and during this time there have been a few teething problems that have now been resolved.

"As a consequence of the trial, traffic queues are forming on the A394, particularly during the evening peak times where queues have been reported to be extending up Sithney Common Hill. Unfortunately the queue lengths cannot be reduced and this is likely to continue until the end of the trial. However, it is anticipated that the queues may reduce in length as drivers become accustom to the trial layout and during the peak hours once the school holidays start.

"We are aware that additional traffic is using St Johns Road and that queues form at the traffic signals by the junction with the A394. The timings of the lights have not been changed but the additional delays are symptomatic of more drivers using this route whereas previously they would have used the Penhellaz Hill junction.

"Covert monitoring has confirmed that some drivers especially those in commercial vehicles are ignoring the right turn ban. CCTV monitoring will be completed within the next week to establish the extent of this problem.”

The spokesperson added that the six-week trial would act as a period of consultation and that any feedback received would be considered alongside the results of monitoring, as well as discussed with local bodies, before any further action is taken.

The early days of the trial came in for criticism when Helston Town Council met.

Town councillor John Boase, who actually lives on Cross Street, confirmed that traffic had reduced there since the trial started, but that there had been so many problems “even as a resident of Cross Street I don’t want to see that happening in the town.”

He reported how a member of the public rang him to say it took 20 minutes to drive down Sithney Common Hill, while he himself tested driving down The Furry and traffic was backed up as far as the Bulwark Road turning.

The problem, he told a meeting of the town council last week, was that cars unable to turn right onto Penzance Road were instead going through St John’s to the traffic lights at Castle Green – which were set up to change as soon as a car was waiting.

“They need to be reprogramed; it’s a side road. Every ten cars coming down Sithney Common Hill are being stopped because the lights change. The survey isn’t really going to have true impact,” he added.

Mr Boase also pointed out that the warning board at the entrance to Cross Street contained so much information that drivers were unable to read it all as they drove past and there was nothing to say that turning was closed until it was too late.

Councillor Tim Grattan-Kane said members of his family had reported to him: “There were people who still carried on driving straight through. There were a couple of occasions when St John’s Road was brought to a standstill.

“A delivery vehicle for Dales [Butchers] had to drive to St John’s Close, to the bottom, because they couldn’t turn round.

“It was absolute chaos at times.”