Construction bosses have revealed the surprising mess of pipes they uncovered beneath the Granite Mile – as they argue that delays to the Union Street revamp have been “unavoidable”.
Engineers working on the £17 million project say they even encountered a mysterious manhole leading 10m underground as they puzzle their way across the section between Market Street the St Nicholas Kirkyard…
This series of “unexpected underground obstacles” was, they stress, “completely uncharted”.
This revelation comes weeks after the council’s retiring chief captial officer, John Wilson, announced the scheme had been waylaid until at least next spring.
Amid a list of reasons, he blamed the delays on “less than required contractor productivity”.
Today, Morrison Construction have hit back with their side of the story – with images showing the unexpected artifacts that have caused the Union Street delays.
What was to blame for the Union Street delays?
Morrison bosses catalogue “historic tram infrastructure, unrecorded utility pipes and cables” among those obstacles buried beneath the street.
More than 20 “unrecorded clusters” were discovered.
Despite the project being in the works for some time, they were “previously undocumented on any maps or diagrams”.
This has all meant the project will extend well beyond its original target of the end of this year.
Gas, electricity and water bodies have now had to visit Union Street to advise on whether these cables and pipes were still live or redundant.
Were they found to be live, they would have to be made safe. If redundant, they could be moved.
The complex process resulted in “unavoidable” delays.
What were the more unusual finds?
Among the more unique finds was an unknown “concrete access shaft” which led down to a 10m deep underground culvert.
Due to the risk of collapse, the access shaft could not be safely removed.
The project team then had to devise an “alternative engineering solution” to redesign the new street drainage system around it.
Old electric tram power cables, dating back more than 120 years and encased in wooden boxes, were also discovered, with eight “running the length of the project site”.
Old metal sleepers from the trams were also found, along with a cast iron carrier pipe running the full length of the 300m site.
How is pavement work progressing?
In March, work began on pavements around what will be the entrance to the new Flint market.
But already, similar problems have emerged.
Nine “unrecorded services” have been discovered during excavations – including two gas pipes.
What do you make of the Union Street delays? Let us know in our comments section below
‘Obstructions can be incredibly frustrating’
Rod Buchan, construction manager for Morrison Construction Infrastructure on the project, has now spoken out.
He said: “Despite the challenges presented by these unexpected underground discoveries, the team remains committed to delivering the much-needed upgrades to Union Street Central.”
And Hub North Scotland project director, John Edwards added: “The project team went to great efforts before works started to determine what lay beneath the ground.
“However, there is always a possibility of finding these uncharted obstructions which can be incredibly frustrating for the site team and can have an impact on progress.
“The team continue to work hard to minimise that for the shops and businesses.”
Read more:
Union Street revamp delayed until 2026 as council blames ‘worker productivity’
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