The opening of a new maternity hospital could face significant delays due to the high presence of a bacteria in its water system, the Belfast Trust has said.

The hospital, at the Royal Victoria site in Belfast, was due to open next year after numerous delays.

The trust took possession of the five-storey building in March and began a “clinical commissioning phase” – a process of ensuring a safe transition of service to the new site.

First reported by PA, the trust said that during testing of water outlets, high levels of Pseudomonas aeruginosa were discovered in the water system.

Pseudomonas infection killed three babies at Belfast’s Royal Jubilee Hospital in 2012.

The infection does not usually affect healthy people but infants and people with weakened immune systems are vulnerable.

The Belfast Trust said it is “developing a remediation plan” for the water systems, which could “significantly impact on timescales for occupation of the building.”

The trust added it acknowledges that, “for a number of reasons”, the new maternity building has taken a long time to complete.

A Northern Ireland Audit Office report earlier this year said the hospital was originally expected to be completed by the end of 2015.

The report said: “Whilst the new maternity hospital has been substantively built it is not operational. The latest estimated date for completion of the final phase of the Maternity Hospital is June 2025, almost 10 years late.

“The original cost estimate was £57 million, with costs now expected to be £97 million.”

The new hospital is expected to have an admission unit, early pregnancy department and an active birthing centre with 10 dedicated rooms for mothers who choose midwifery-led care.

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Also included in the development is a new neonatal unit with 45 cots.

A 10 bed ward is also located directly above the theatres to facilitate the care of high risk antenatal and postnatal women.

“Whilst this further delay is very disappointing, the safety of new mothers and their babies is our main priority,” the trust added.

“We will continue to address the required remedial works in order to ensure the building is safe to open to provide high quality care for women and their babies.”

Pseudomonas aeruginosa is the definition of a tough bacterial strain, able to survive in harsh environments.

It is found widely in soil and stagnant water, and can infect humans and plants.

It does not usually cause illness in healthy people, but is described as an “opportunistic” organism, causing serious infection when our normal defences are weakened.

This means that it represents a genuine threat to the most vulnerable hospital patients, most commonly intensive care patients, those with depleted immune systems such as cancer patients, people with severe burns and premature babies in neonatal units.

Several babies have died in Northern Ireland from the bacteria.