Sewage has stopped seeping into Balluta Bay after repairs on a leaky storm drain tunnel, the Water Services Corporation (WSC) said on Friday.

However, the bay will not reopen for swimming until the health authorities give the go-ahead.

A spokesperson for the health ministry said: “The bay will be reopened by the health authorities once the site meets all quality standards and is fully compliant with the required tests.”

Blockages are a huge headache for the Water Services Corporation. Photo: WSC

Water Services Corporation CEO Karl Cilia said two instances of E. coli contamination in Balluta were not from the sewage system, but the corporation still assisted in the necessary repairs.

Balluta Bay has been closed since May after health authorities announced two separate instances of E. coli contamination. E. coli is most commonly attributable to untreated sewage.

Mystery surrounds source of contamination

A “commercial entity” was found to be the source of one case. In that instance, the health authorities resolved the issue, Cilia said.

The health ministry was asked whether it is investigating anyone for contaminating the bay, but it did not answer that question.

The second source of contamination was coming from a stormwater tunnel that ends in Balluta Bay, Cilia said.

The tunnel, which falls under the responsibility of the Public Works Department, is old and structurally damaged, he said.

“The water that was coming from there was contaminated.”

Cilia said cracks in the tunnel caused sewage water to leak into it, eventually ending up in the sea.

“We closed the cracks so that the sewage would stop leaking,” he said.

The source of that sewage was unclear, he said.

More work on the tunnel is needed, and there are ongoing repairs with the Public Works Department to structurally secure it, Cilia said.

“Almost all cases of seawater contamination are not caused by Water Services,” the WSC CEO said.

When the WSC is responsible for contamination, it is because a drainage pipe is blocked, causing sewage to seep through a manhole, he said.

Blocked drainage can lead to backflow entering people’s homes

Blockages are a huge problem for the WSC and people often flush items like hand wipes, cotton buds, hair and sanitary pads. They do not degrade in water and end up as part of large balls that block drainpipes.

“Blocked drainage can lead to backflow entering people’s homes,” Cilia said.

People also dump materials into manholes. “We’ve found teddy bears, towels, and even animal carcasses thrown into the sewage main pipe,” he said.

And restaurants, he added, pour fats and oils into manholes.

Last June, a towel caused a blockage in Birżebbuġa, leading to contamination at St George’s Bay.

The WSC, he said, does not have the authority to fine people for dumping items into sewers; that remit belongs to health authorities.