The planning authority has approved an extension to a controversial development incorporating Sliema’s old naval clinic, on the site known as Il-Pjazzetta.

The Gasan development, which was approved in 2014, features an eight-storey complex containing offices, retail outlets, apartments and underlying garages.

Prior to its approval, the proposal had attracted the ire of residents and heritage groups because of risks to an underlying air-raid shelter, which the Heritage Superintendence referred to as a “subterranean rock-cut corridor” and which would be destroyed by the development.

Concerns were also raised over possible damage to an extensive and fragile cave system, including the iconic Għar il-Lembi and Għar id-Dud caves, as well as the aesthetic impact of the development, which will protrude from behind the façade of the old naval clinic.

The proposal had attracted the ire of residents and heritage groups

However, the extension approved yesterday, which involves demolishing a building on High Street and amalgamating it into the new development, met with no objections and was approved unanimously by the Mepa board.

The extension includes a number of minor alterations, including the relocation of the garage entrance to the adjoining basement garages and change of use of an existing garage ramp to a retail outlet, as well as the construction of a pool over the penthouse level.

The Environment Protection Directorate, which had previously called for the underground car park to be scaled down to minimise the risk of collapse of the cave system, noted that the proposed extension of the car park was further away from the underlying cave system and therefore did not raise any concerns.

Mepa carried over a number of conditions and bank guarantees from the original proposal, including the requirement for the developers to restore the existing façade of the naval clinic and incorporate it into the design.