On Monday, underneath the busy roads of San Gwann, 50 meters underground a tunnel was being drilled from the Pembroke Reverse Osmosis plant to the Ta’ Qali Reservoirs. This was a significant milestone, being the second of three scheduled tunnel break-throughs.

The Ta’ Qali –Pembroke Tunnel is a 9.5km tunnel linking Pembroke reverse osmosis to reservoirs in Ta Qali. The project is intended to improve the overall water quality in many parts of Malta and improve operational efficiency and environmental sustainability.

The tunnel will house two pipelines, one to deliver water to Ta’Qali and the other to be used to supply good quality blended water to the central part of the island through a centralised hub feeding mainly via gravity- therefore no need of pumps. A total of around 3,000 tonnes of pipework and fittings will be laid in the tunnel.

“The Ta’ Qali- Pembroke tunnel is a €30 million project and today we see that 7km out of 9.5km is ready,” Minister for Energy and Water Michael Farrugia told The Malta Independent, who was visiting the tunnel being drilled.

The project is forms part of the Water Services Corporation’s ‘Net Zero Impact Utility’ project, which is coordinated by the Water Services Corporation and is co-financed through EU Cohesion funds.

Farrugia explained that the intention of the tunnels will have a huge environmental impact, as it will improve the quality of water and that slowly will reduce the use of CO2.

“We are calculating that in the first quarter of 2021 we will finish the tunnels, of course all the piping will have to be finalised too and systems, so we are seeing that by the end of summer 2021 operations would have begun, of course keeping in mind we work within the limits of the pandemic we are facing and affect the project,” explained Farrugia.

The tunnel boring works are being carried out by the Bonnici Bros. Services Ltd. The tunnel will be crucial asset for the Corporation and will allow it to link its largest Reverse Osmosis plant in Pembroke to the Ta’ Qali Group of Reservoirs via large diameter 1.2m mains. This will ensure that all the blending potential of RO water is exploited and pumping energy reduced to the barest minimum, therefore giving better efficiency and optimal environmental performance. The reduction of pumping losses will mean crucial savings in electricity used for pumping as well as hundreds of tonnes of chlorine per year.

The production and supply of the large diameter glass fibre reinforced plastic (GRP) pipes inside the tunnels are entrusted by the Turkish company Superlit Boru Sanayi A.S.  These pipes are a first for Malta. 

 Photos: Michael Camilleri