Mental health advocates claim the psychiatric unit at Sir Charles Gairdner Hospital is unfit for patients, citing mouldy showers, air-conditioning vents covered in cobwebs and rats in a courtyard.
Long-time mental health activist Margaret Cook took photographs last month of a rusty showerhead, mouldy shower tiles and general disrepair in D20, a 36-bed ward for voluntary patients, while visiting Sara Elliott who was being treated for depression.
The pair said they saw big rats in a courtyard adjacent to the unit and were later told by staff they had tried unsuccessfully to get rid of them using bait.
Ms Cook was so appalled by the state of decay that she sent the photographs to Federal Mental Health Minister Mark Butler, WA's Mental Health Minister Helen Morton and Mental Health Commissioner Eddie Bartnik.
She said the unit was not meeting basic public health standards and in any other hospital setting would not be allowed to operate.
While the State Government was building a 30-bed mental health unit at QEII Medical Centre to replace D20, Ms Cook said hygiene standards were dropping at the existing unit.
"It's degrading to mental health patients who are already very vulnerable but are often too scared to complain because they feel they don't have any rights," Ms Cook said. "The showers are so bad I wouldn't wash a dog in them."
Ms Elliott said staff did what they could but were clearly hampered by a lack of funding to do basic maintenance.
"The staff are fantastic but their duty of care is being compromised, and it's discrimination against mental health patients who are often very unwell and are being treated like the poor relations," she said.
"There's no way those conditions would be tolerated in other parts of the hospital."
Sandra Boulter from the Mental Health Law Centre said she had concerns about D20 as well as wards at Graylands Hospital.
"Whenever I visit the more gloomy and unkempt wards, I wonder how they are conducive to recovery," she said.
By yesterday SCGH appeared to have rectified some issues raised by Ms Cook, saying not all her photos "accurately represented the current state of the ward".
A North Metropolitan Health Service Mental Health spokeswoman said the new mental health unit was due to be finished late next year.
Though regular maintenance and cleaning was still being carried out on D20, the facility was ageing.