The Water Services Corporation is delighted to announce that the operation to replace the broken section of the Gozo sewage outfall was successfully concluded.
On Thursday 22 August, work started on fitting two vessels in Grand harbour with specialised machinery and testing was concluded by early Monday 26th August. The vessels then set sail for Gozo with the main one being moored offshore from the sewage plant for the entire operation. Early Tuesday morning the divers entered the compression chamber and were lowered to a depth of 60-90m to start works on the outfall.
During this period the divers were confined to this chamber and worked for eight hours a day, 4 hours at a time, with one diver working on the outfall and the other on standby in the specialised bell to provide assistance in case of safety issues. The divers were given step-by-step instructions from the control facility on the main vessel. The utmost attention was given to the wellbeing of the divers and even their body temperature was regulated by special heated suits.
The divers first installed a special fitting to the old outfall so that the new pipes could be secured. Tailormade S-bends were also used to compensate for the sharp drops in depth. The last pipe section was attached together with a tailor-made diffuser to greatly improve the performance of the outfall. On Friday the outfall was secured in place and following this, with the divers safely inside the onboard decompression chamber, the ships sailed back to the Grand Harbour. The divers exited the decompression chamber late on 2nd September and are still on standby on the vessel in close proximity to the safety facilities just in case these are required.
A cost of around Half a Million Euro
This complex operation cost around half a million Euro and also required the invaluable input of local Port and Maritime Authority.
Damage to the outfall was caused by years of illegal sewer discharges that literally wreak havoc in the sewage infrastructure. The materials discharged range from tonnes of animal waste to domestic items such as cleaning and baby wipes. To complement these investments the Corporation is working on a holistic strategy that will significantly improve the monitoring of the sewers and the deterrents for those who may still abuse the system.
CEO Richard Bilocca thanked the workers for successfully completing this very complex operation whilst also emphasising that although the Corporation went for the best design on the market, this could still be prone to damage and if abused again, the damages may recur which would have worse consequences due to the sensitivity of the new diffuser.