Cause of cracked paving in Diss may never be known
The cause of cracked paving on a recently-revamped town centre street may never be known.
Norfolk County Council have said that the results of laboratory testing on Market Hill in Diss – where cracks first appeared last September – have proven inconclusive and that it may never be possible to establish the exact cause.
The council also offered no guarantees the cracks would not appear again after the paving is repaired using a “more robust method” later this month. It will be the fourth time the paving has been relaid and imprinted with the current cobble effect, with three attempts made during the original construction period.
Residents living opposite the area, where the work will be carried out over 14 nights from September 10, between 7pm and 7am, were shocked by the news.
One resident, who lives in Mallard Court, said: “During the three months the work was carried out, we went through a living hell.
“Apart from the roads being closed, the sound from the machinery was amplified through the entrance and we couldn’t even sleep.
"Now we have to go through it all again."
The Heritage Triangle project began in 2009 when a bid was submitted to the regional Heritage Lottery Fund (HLF) to regenerate the Corn Hall.
More extensive plans were then submitted to meet wider national HLF criteria, which encourages community regeneration and heritage promotion.
The Heritage Triangle project, which also included St Nicholas Street, Market Place and Market Hill, the Mere boardwalk and gardens received £3.4 million from backers including the HLF, South Norfolk Council, Diss Town Council, Norfolk County Council, local residents and other sources.
It was later shortlisted for several regional and national awards including those by the Royal Town Planning Institute.
The same paving imprint method to create the cobble effect was used on all the pavements in the area - but only Market Hill has cracked.
According to Sheila Moss King, programme manager for the Diss Heritage Triangle and Corn Project, during the work, the ground under the pavement was discovered to be complex mix of Victorian cobbles, elements from the medieval streetscape, sewers, rain water, electrical cables, gas mains, telephone lines, water connections, some of which are close to the surface.
She said: “It would have been great if Norfolk county council highway’s extensive investigative work had come up with definitive findings as to why the imprint failed immediately in this specific area. But the fact that they are going ahead with remediation is good news.
“We’re grateful that they’ve taken the decision to schedule the work overnight – this adds to their costs but shows real sensitivity to the needs of local businesses.”
Several business in the triangle said that the construction work over three months last year had a severe impact on takings, with two businesses calling the work, the “final straw”.
Diss Antiques said that losses made forced the decision to relocate and the Gluten Free Food Store closed in June, staying trade had not returned.
Diss town council said of the remedial work: “We have been pushing for Norfolk county council highways to resolve the quality issues affecting the imprint.
“This has taken a considerable time because the county council has had to undertake laboratory analysis to determine the causes, and then has been working with its various subcontractors to agree a remediation approach.
“They now have achieved this and have scheduled the work accordingly.
“They will also be replacing a number of cracked hazard paving slabs around the triangle at the same time.”
According to Peter Hyde chairman of the Heritage Triangle Trust, the imprint method had been a “Plan B” as granite setts the trust had wanted would have been too expensive.
Mr Hyde, said: “The Diss Heritage Triangle Trust and the Market Hill traders, just want the work to be done as soon as possible and during the night.
“We hope that the more robust specification, will be combined with some stringent quality control, to bring an end to the problems, once and for all.”
A spokesman for the county council said: “We are working to get the problem with the surface fixed as quickly as possible.
“Since we raised concerns last year that there were issues with the surface, we’ve done a lot of work, including lab testing samples of the surface, to investigate the cause of the problem.
“While it may never be possible to establish the exact cause, what is certain is that the damaged surface needs to be replaced, and work to do this is due to start next month.
“We are talking with the principal contractor to establish who is liable for the costs of the repair work.”
Asked if there was any guarantee the fourth attempt would solve the problems, the council said: “A more robust specification will be applied to these remedial works as a result of our investigations.”
Main contractor Tarmac, said: “We are continuing to work closely with the team at Norfolk county council to support ongoing investigations and rectify the issue as soon as possible.
“The remedial works have been programmed for completion at night to ensure minimal disruption to local businesses and the general public.”
Ed Adkins, of Adkins Opticians, which is next to the planned work, said: “We were aware there were issues due to cracks reappearing, but felt it was probably as good as it was going to get.
“Hopefully, this time they will resolve the issues permanently.”