Currently 10 weeks behind schedule, the Promenade reconstruction project is inevitably being carried out under the glare of public scrutiny.

There’s been criticism about lack of parking, access and communication and about the scale of disruption with large sections of the seafront fenced off.

But since the problems with delays and cracked concrete were confirmed last month, work has progressed very well, said project manager Keith Podmore, of the Department of Infrastructure’s highway services division.

And he is confident that the first part of the new promenade - at the Strathallan end - will be completed before Christmas.

Completion of the project, scheduled for October 2020, can’t come too soon for businesses who say they are really struggling.

Mr Podmore, said: ’We always knew the job was going to be difficult and it was going to be disruptive.

’We’ve tried to be proactive and reactive. We have been in contact with all the businesses along the promenade. We have listened and we have taken the criticism on board. We have improved communications.’

While work has progressed well in recent weeks, the project remains about 10 weeks behind schedule but Mr Podmore added: ’I don’t think we’ve lost any more time.’

One of the main reasons for the delays is that no one knows where all the old services are as no records exist for them and trial holes had to be dug to find them. An old mains water main was discovered at the bottom of Summerhill, for example.

All the old services are being replaced, including the gas main. And the new services are being laid at a greater depth.

Many people are surprised that the contractors are not having to excavate deeper, given the underlying problems with the prom’s failing substructure. Maximum excavation depth is about 400-450mm and about 1.7m for the services.

But Mr Podmore explained the problem lay with the concrete slabs beneath the road. The slabs are in poor condition, tilting in places and crumbling to the touch.

Below them, however, no voids have been found during surveys or the current works.

About a quarter of the promenade has been excavated so far. New concrete foundations have been laid under the tram tracks but a new flexible method of construction is being used for roadway itself.

This involves 150mm of compacted aggregate over a geotextile membrane and then three layers of asphalt - a 160mm base course and a 60mm binder course topped by a 40mm surface course.

A 470m section of the tram line has reopened from Strathallan to Marathon Terrace and it is hoped the line will be extended to the Palace by the time of the Festival of Motorcycling.

Work on the southern section, where a single tram line will run along the seaward side of the road, will begin some time in October or November.

Contractors admit the project would have been easier without the tram tracks.

Mr Podmore said the tram corridor was being done first as there was a ’contractual obligation’ to provide a horse tram service. The distance between the twin tram tracks is wider, by about 300mm, to comply with modern standards, he said, and it’s nothing to do with future ambitions to run modern trams or extend the MER along the prom.

Mr Podmore said any such move would mean battery powered trams so there would be no need to install overhead electric cables or an underground conduit.

CRACKS

Cracks found in the surface of red concrete used for the tram corridor are still being investigated. ’There could be several reasons for the cracks,’ said Mr Podmore. ’It’s something to do with the concrete itself.’

The solution has involved laying a metal mesh under new cement but the concrete already laid is not having to be replaced.

Some 38% of the promenade is being worked on at any one time. Mr Podmore said to get the scheme done in the quickest possible time meant working on multiple fronts.

During excavations part of the old sea wall have been found.

Work is currently well advanced on the seaside carriageway between Strathallan and the pumping station opposite the Queen’s Hotel.

When work is sufficiently far advanced on the next section to the Palace, the landside carriageway from Strathallan will be done - and the first bit of the new promenade will be complete, sometime before Christmas.

Mr Podmore said: ’It’s probably the biggest highways scheme the island has seen in the recent past. There are a lot of competing priorities.

’It’s very exciting and when it’s finished we will have a fantastic promenade to be proud of.’