- Arches uncovered during Newcomen Street road works (Photo: Ann Hardy)
- Arches uncovered during Newcommon Street road works (Photo: Ann Hardy)
Ann Hardy brought to the Committee’s attention recent photographs that she had taken of interesting arch structures uncovered during the excavations currently being undertaken on Newcomen Street Newcastle.
At the Coal River Working Party’s June meeting it was suggested by our archaeologists and historians that the structures could be pre-1860, and that it be urgently requested that construction work cease immediately in order to investigate the structures from an archaeological point of view.
We would like to know what they are, how old they are, and whether an archaeologist has been present during these roadworks. The Heritage Branch in Sydney has also been notified.
Newcastle's Old Government Domain (1804) 
Something for a structural engineer to think about?
There was something similar found in King street after the retaining wall “recently” fell down.
That retaining wall has collapsed more than once in its life but the arch behind the wall has not. The Newcastle Club buildings still stand as a result.
The ground behind the wall is sand and maybe an arch was installed to reduce the pressure of the sand on the wall by reducing the weight and moving the force of the load back and away from the actual wall?
Another possible reason for an arch is that it provides an anchor into the ground that adheres the wall to the hill side with a greater surface area.
Could be that the buttress system on a cathedral might have been employed in another manner.
A final thought is that if the arch was not filled, like in King Street, the void between the wall and within the arch could allow for drainage of water that would otherwise build up hydraulic pressure against the wall. This was the case with this wall and the retaining wall beneath the bowling club in King Edward Park.
In regards to later the pressure was so great that when it was released it apparently went off like a bomb.
These theories are based on history not academic qualifications.