Enemalta chairman Frederick Azzopardi apologised for the nationwide outage on Tuesday that was triggered by a faulty cable outside the Marsa distribution centre. Photo: Paul Spiteri Lucas

An underground cable that had a fault so bad it caused the road surface to crack kick-started a chain of events that led to Tuesday’s nationwide power outage.

Enemalta chairman Frederick Azzopardi yesterday ruled out the cable being damaged by a contractor and said an internal investigation was under way to establish what caused the fault.

“At this preliminary stage there is no indication of foul play,” he said.

The cable feeds into Marsa South Distribution Centre at the Marsa industrial estate and the fault occurred beneath a road situated a block away from the building.

The fault sparked a fire at the distribution centre that eventually led to an explosion. The accident forced the Delimara and Marsa power stations to trip, leading to the nationwide blackout. The Marsa centre is an important cog in Enemalta’s distribution network, supplying electricity to the south of the island.

Mr Azzopardi said the explosion did not cause structural problems but equipment was damaged. He said the cost was “substantial” but could not quantify the amount, saying a verification process was still under way.

At this preliminary stage there is no indication of foul play

While electricity was restored to many localities throughout the early hours of Wednesday after a second blackout, residents in Luqa, Qormi, Żebbuġ and parts of Siġġiewi were still without power early yesterday afternoon.

Electricity was fully restored to all Malta and Gozo by 3pm. Mr Azzopardi apologised for the outage and explained that the localities directly linked to the distribution centre had to wait longer to have electricity restored until all safety checks were carried out.

Trenching works were being carried out yesterday at two sites in the vicinity of the distribution centre as part of the repairs to the faulty cable, which seems to have overheated, while engineers were working on the distribution centre.

Mr Azzopardi said the first priority on Tuesday night was to ensure that the fire was contained, preventing it from spreading to other parts of the distribution centre.

He ruled out that the power cut was a result of an increase in demand, insisting the company had “a spinning reserve” – extra capacity – of 60MW at the time of the total shutdown.

Given the extent of the damage, the police are conducting an investigation and a magisterial inquiry is under way.

ksansone@timesofmalta.com