By Christine Lavelle
A SPECIALIST rope squad called in over safety fears at Edinburgh Castle have been forced to remove four tonnes of volcanic rock from its world famous cliff face.
Roads beneath the huge castle rock were ordered to close earlier this month after large chunks of stone were dislodged during heavy rain falls, crashing onto the roads and pavement below.
Although no-one was hurt, passers-by on September 23 reported ‘bread loaf’ size boulders being among the debris which forced City of Edinburgh Council and Lothian and Borders Police to seal off access.
Historic Scotland have now deemed Johnston Terrace safe enough for use by members of the public, following an investigation carried out on the castle’s rock face.
But the results of a Freedom of Information Inquiry has revealed that geo-technical engineers and a rope squad have removed “three or four tones” of rock and plant materials.
In his FOI response David Storrar, regional architect for Historic Scotland, said: “Several fragments of rock fell onto Johnston Terrace, with a total estimated weight of approximately 25 kg.
“Following the initial rock fall event at Edinburgh Castle, a tactile and visual inspection of the south rock face over an area of approximately 2,000 square metres – 40 metres wide by 50 metres drop – was carried out by the geo-technical engineer and rope squad.
“Approximately three to four tonnes of rock and plant materials were removed over a two week period.”
Further inspections are to be carried out over the next three weeks, with an abseiling team set to descend on the castle’s rocky slope.
But Johnston Terrace will remain open and only the footpath will be affected.
A spokeswoman for Historic Scotland said: “The Historic Scotland rope squad, under the supervision of a specialist geo-technical engineer, has completed close visual inspections of the rock face, carefully removing any rock, which might become loose through the process of natural erosion.
“The team will now move back onto their programmed pro-active inspections on the north face of the rock.
“Similar inspections and rock scaling will be carried out there over the next two to three weeks – weather permitting.
“The abseiling team will be visible from Princes Street.
“The footpath immediately below will be closed for the duration of the works, but the railway and footpath-bridge between Castle Terrace and Princes Street Gardens will be unaffected.
“It took us longer than planned to agree the road was safe enough to be reopened, because we wanted to be absolutely sure it was safe.
“The area is completely safe, there is no way we would have reopened the road if there was any kind of safety issue.”
It is not the first time rocks have fallen onto the road.
Last year Historic Scotland looked into covering the rock face in wire mesh, but it was met with opposition.
City centre councillors have called for the organisation to seriously consider new safety measures that would prevent any debris falling again.
Conservative councillor Joanna Mowat said a solution had to be reached before a passer-by was injured or property was badly damaged.
She said: “We’ll have to discuss maintaining the wall because it is clearly not safe.
“I appreciate that the castle is a historical landmark, and while something like wire mesh is not attractive, the safety of pedestrians is paramount.”
Following the reported fall, the road was immediately closed and barriers were put in place.
The 2,000 square metre area was closely inspected by the geo-technical engineer and rope squad, who removed loose rock and surface debris.
Mr Storrar said: “On completion of the plant removal and rock scaling exercise, the geo-technical engineer re-inspected the area and signed off the works before the road was re-opened on 8 October.
“The south slope area will be re-visited and re-inspected in May 2011, as previously planned.”
The spokeswoman added: “This is an important issue which requires to be resolved as soon as possible.
“Historic Scotland is working closely with Edinburgh City Council and is assessing a number of possible options in partnership with the council.”