Lead contamination in the water supply of Perth’s new children’s hospital likely came from disturbed residues in the surrounding ring main and lead leaching from fittings and fixtures in hospital plumbing, an audit has found.
State Building Commissioner Peter Gow handed down his findings after more than 1000 individual tests by the State Government, the building and plumbing contractors since May 2016.
“Residues containing lead were most probably drawn from the Queen Elizabeth II (QEII) ring main into the Perth Children’s Hospital (PCH) when water flows in the ring main were disturbed in early 2016 as part of commissioning the PCH,” Gow said.
“Testing of water flowing in the QEII Medical Centre ring main in the second half of 2016 and in 2017 predominantly shows lead levels below the Australian Drinking Water Guidelines.”
The QEII ring main was part of the Water Corporation supply network before being handed over to the North Metropolitan Health Service which now controls and maintains it.
The audit found no evidence of lead contamination from the Water Corporation scheme feeding into the medical precinct.
“Water being drawn from the ring main is not a continuing source of lead. The lead detected in end-point testing from mid-2016 onwards came from sources already in the PCH plumbing – either residues already in the piping, including residues drawn from the ring main in early 2016, or directly from the brass fittings,” Gow said.
“When the residues in PCH are eliminated, lead leaching directly from brass fittings remains the only significant source of lead.”
John Holland Pty Ltd is the main building contractor for the Perth Children’s Hospital.
The construction company’s WA Region Manager Lindsay Albonico told the ABC he welcomed the commission’s findings.
“In late January this year, John Holland confirmed publicly that its extensive water testing regime had pointed to the ring main as the problem,” Albonico said.
But he added “urgent questions” were being asked of the Building Commission after a draft version of the report provided to the company differed “significantly” to the final version.
The audit of contractor and product performance concluded there were no grounds for immediate disciplinary action related to the areas audited.
But a statement from the Building Commission said: “the delayed completion, complaints, material failures and contractual disputes suggest the registered building contractor may have failed to properly manage and supervise the project.”