A scheme to complete infilling work on a Victorian tunnel with a tragic past has been completed by contractors working for the Historical Railway Estate.
AmcoGiffen has successfully finished a three-month programme at Clifton Hall Tunnel in Pendlebury, Greater Manchester. The tunnel gained notoriety in the 1950’s when the collapse of a construction shaft resulted in five fatalities. Four houses on the street above were also lost.
Afterwards, the tunnel was closed and partially infilled but a few voids were left that have now been filled to ensure the tunnel remains safe for generations to come.
HRE Engineer Andrew Willison explained: “National Highways took over managing the HRE in 2013 and since then regular safety checks have been carried out at Clifton Hall.
“We decided to fill the remaining voids as a precautionary measure and to ensure the site remains safe for the future.”
Before work started AmcoGiffen used a cavity auto laser scanner which was lowered down drill holes to provide 3D imagery of the voids.
Dave Martin, Contracts Manager at AmcoGiffen said: “The technology is new to us as there are very few of these in the UK. The imagery helped us to calculate the volume of materials required to fill areas of the tunnel with voids present, one of 200 metres long and the other 150 metres long.
“Both sections had five holes drilled that we used to insert the cavity scanner and to pump the materials during the filling stage. In total 2,200 tonnes of material was needed to fill the voids.”
A mixture of cement and fly ash was used in the voids as cement alone would be too strong and would not flow far enough, as it needed to travel 30 metres. Fly ash is made from combusted pulverised coal and added to the cement to increase workability and durability, which means wastage is reduced.
Pumping the materials during the filling stage took 10-weeks working day shifts to keep noise to a minimum for residents nearby.
Some of the drill hole locations were changed to help protect trees and the access areas have been reseeded to ensure the natural habitat regrows.
Members of the project team recently visited St Augustine’s CE Primary School, which, sits next to Clifton Hall Tunnel, to give pupils an insight into the work being carried out. AmcoGiffen also returned to St Augustine’s to clear vegetation, lay artificial grass, paint planters and build an arbour in the school’s Peace Garden as well as working on the early years playground.
History
Constructed in the 1846 Clifton Hall Tunnel, which locally took the name of its dark-whiskered foreman, ‘Black Harry’ formed part of the Patricroft to Molyneux Junction line and is a double track horseshoe shaped tunnel measuring 1187 metres long and lined throughout with brick. Its construction was difficult from the beginning as the ground was very unstable where mining had already taken place.
The surrounding area was subject to intense urbanisation with the need for homes being built directly above the tunnel and there were several rounds of remedial works including the addition of steel ribbing to provide additional support.
Salford City Council granted planning permission for the scheme in May 2024 and AmcoGiffen started work in November.
Following a partial collapse on 13 April 1953 all trains were stopped and inspection carried out. Two weeks later the tunnel roof failed, directly beneath an old construction shaft.
Witness accounts from residents living above the tunnel described hearing a loud cracking noise at 5:35am, followed by two houses, numbers 22 and 24 Temple Drive, collapsing to the ground. The tragedy resulted in five fatalities and the tunnel was never reopened.
