These traffic lights were built on a roundabout as part of a £3.5m scheme four years ago - but they still haven’t been switched on.

The part-time traffic lights, designed to tackle congestion, have remained switched off since they were erected in June 2010.

Despite the huge outlay, they’ve remained off as traffic at the roundabout in Preston, Lancashire, hasn’t been serious enough to switch them on.

The lights were put in place as part of a number of traffic schemes in the area, paid for by United Utilities at a cost of about £3.5m.

They formed part of a major scheme to prevent water pollution, which was taking place at the time.

Paul Dunne, highways manager for Preston, Lancs., said United Utilities had paid a contribution towards future traffic management for the area at the time.

He said: 'When United Utilities were doing major works in this area, we took the opportunity to seek a contribution from them towards the future needs of traffic management in Riversway. The lights are part of a £3.5m scheme from 2010.

Useless: Until congestion worsens in the area, the traffic lights serve no purpose.

'One of the projects which resulted as part of a wider scheme of works to prevent congestion is the part-time traffic lights at Mariners Way.'

Mr Dunne said other improvements had thus far 'kept traffic flowing well', but as it increased, drivers would begin to benefit from congestion-busting measures.

He said: 'Improvements at other junctions made as part of this scheme have kept traffic flowing well, which mean that traffic has not yet reached the level needed to trigger the part-time lights.

'However, as this area of Preston continues to develop, weight of traffic will increase and drivers will begin to benefit from all the measures we've taken to prevent and manage congestion.'

Coun Bhilhu Patel, who represents Riversway on Preston Council, said it was 'fortunate' that some of the traffic measures had not been needed.

He said: 'Lots of money was spent by United Utilities on all junctions trying to benefit traffic flow, and the area benefited.

'But I think we've been very fortunate that some of the systems that were created have not had to be used.'