A top geologist has hit back at a structural engineer's assurances that a sea cave in Tigné posed no threat to the stability of an overlying tower being built above.
Peter Gatt said studies cited in defence of the tower’s safety were not necessarily accurate and insisted that fractures in the underlying rock extended several metres below sea-level.
The geologist had first raised concerns earlier this month after photos showed the tower block on the north face of the Tigné peninsula, the latest addition to the Midi development, perched on fissured rocks and a cave.
Dr Gatt said the rock was part of the foundation of the building and warned that if the sea cliff failed, there would be nothing holding up the high rise over it.
The warnings were dismissed by Alex Torpiano, a structural engineer involved in the design, who said the claims were “completely unfounded”.
Prof. Torpiano insisted that the fissures and caves were well known to engineers and that the building was designed accordingly – to ensure there was no risk of collapse.
Studies may not always be accurate and rocks have a very complex nature which we can never fully understand
He also said the building’s foundations were underneath the road tunnel linking Qui-si-Sana to the Sliema Ferries, well below the level of the fissures and cave. However, writing on Facebook yesterday, Dr Gatt defended his original assessment.
“Studies may not always be accurate and rocks have a very complex nature which we can never fully understand,” he said, citing the inaccurate geological studies which accompanied the nearby Townsquare development.
“Indeed, Torpiano had publicly admitted many years ago that pile foundations for high-rise building in the Midi Tigné project had penetrated caverns unknown to engineers.
“Torpiano’s comments do not reassure the public. He claims that building foundations are at a lower level than the fractured rocks. It has to be said that the oblique fractures shown in the photo (which pose the greatest danger) extend to several metres below sea-level.”
Dr Gatt added that a tunnel excavated behind the sea cave had further weakened the precarious structure, which now consists of a narrow wall of fractured rock unsupported on both the seaward and landward sides.
“The fractures along the sea cliff represent a classic scenario for rapid erosion and failure,” he said. “Even the most rudimentary study would have shown that the sea cliff will fail. The question is not if, but when it will fail, and whether rocks will be dislodged seawards or landwards where they will directly damage the built structures.”