A proposal to build a five-storey block in Birżebbuġa close to a cave of “archaeological and scientific” importance is fuelling concerns it might compromise the subterranean structure.

Known as Għar il-Friefet (Bats’ Cave), it comprises a number of chambers linked by tunnels and is home to a large colony of bats and rare species of invertebrates.

The cave has been threatened by development since the late 1980s as it is nowadays in the midst of a residential area.

However, in 2009, the Planning Authority had intervened by amending the local plan to introduce a buffer zone around it where excavation is not allowed.

Last May, an application was filed to demolish a house very close to the cave in Triq Herakles corner with Triq De Redin to make way for a five-storey block with 10 flats and two maisonettes.

Of particular concern is the fact that the applicant is also seeking to excavate the site for a basement parking facility.

The Birżebbuġa local council is objecting on the grounds that the proposed excavation would be “too close” to Għar il-Friefet.

It notes that in line with a permit for a separate nearby development issued in 2016, a buffer zone of at least 15 metres should be imposed within which no excavation works should be allowed.

A photo of the caves taken from a 2004 study.

The council called for a revision of the plans, presumably the total or partial elimination of the basement level.

The submissions received by the objectors so far during the public consultation period include a report which the PA had commissioned in 2004 to assess the cave’s structural integrity due to a separate development application.

Back then, there was evidence that parts of the roof had collapsed due to fragility of the cave system, though not necessarily due to neighbouring developments. The report is being cited as evidence that the cave cannot sustain further loads.

However, the Superintendence for Cultural Heritage is not objecting despite acknowledging that the application lies within an area of archaeological sensitivity due to its proximity to Għar Dalam and Borġ in-Nadur.

It noted that following “extensive archaeological evaluation” no archaeological features were found within it and that the proposed excavation was “limited to an area away” from the cave.

It said a method statement should be provided by the developer, works monitored, and that plans might have to change in case cultural heritage features are discovered. 

Objections have also been submitted by Moviment Graffitti and Flimkien Għal Ambjent Aħjar, who cited the buffer zone regulations banning excavations works and the possible threats to the cave and neighbouring residents.