The family of an 11-year-old Perth girl who received an electric shock from a garden tap says she has suffered a "catastrophic brain injury" and doctors do not think she will survive when she is taken off life support.

It follows the results of an MRI test on Denishar Woods at Princess Margaret Hospital to determine the extent of the brain damage she sustained as a result of the accident.

Denishar's mother, Lacey Harrison, said even if her daughter does survive, she "will be in a vegetative state".

Doctors have told Denishar Woods's family she is unlikely to recover from her injuries. ( Supplied )

"Once they pull the tubes out she's got to see if she can breathe, but that's as much as her life represents anymore," she said.

"There's no quality of life in her … there's nothing of my little girl left in there."

Denishar's aunt said doctors have told the family they don't think she will ever recover.

"That is what the doctor believes. He does not think that she can recover or will recover, he thinks the best outcome is she can just breathe, and that's no life for a little girl like her," Katrina Harrison said.

Doctors are expected to temporarily take Denishar off life support today to test if she can breathe on her own.

Her family said if that was unsuccessful, another attempt would be made in a few days.

Ms Harrison said if Denishar was not able to breathe independently then, she would be put back on life support "for as long as I need".

"How can you make a decision? She's in there but she's not," she said.

"I can't watch her suffer now.

"Unless there's a miracle in there, which I believe, which I want to believe — that she's going to fight the odds of the medical expertise."

Denishar was shocked when she went to turn off a garden tap at her home. ( Supplied )

Accident 'should have never happened'

Denishar suffered a massive electric shock when she tried to turn off a garden tap on Saturday night at her Department of Housing home in Beldon, in Perth's north.

The shock from the tap hit Denishar with a surge of up to 250 volts of electricity. ( ABC News: Irena Ceranic )

She had been placed on a cooling pad in hospital to try to limit the heat damage to her internal organs.

Ms Harrison is demanding answers from authorities about what happened.

"I will get those answers and it has to be sooner rather than later," she said.

"They've destroyed me and my family's life, they've taken away my girl and I can't get her back."

"She was there one minute, gone the next, through something that should have never happened," Katrina Harrison said.

Denishar's family rallied around her mother Lacey Harrison outside hospital. ( ABC News: Hugh Sando )

Power surge five times dangerous level

Denishar's mother was also injured in the accident as she tried to drag her daughter out of a pool of electrified water.

Ms Harrison was watering her garden on Saturday night when the power to the house went out, and when she went to the meter box to turn the power back on, she received a small electric shock.

She said she contacted the Department of Housing's emergency line to notify them of the fault, but was not given a warning not to touch anything.

Denishar then went to turn off the garden hose and was instantly gripped by a massive electrical current.

The electric shock has been blamed on a malfunction in the property's electricity supply, known as an "open circuit neutral".

It hit Denishar with a surge of up to 250 volts of electricity, which is five times the amount that can cause serious damage to the human body.

Finger pointed at Department of Housing

The accident happened at the family's state housing property in Beldon, in Perth's north. ( ABC News: Irena Ceranic )

Katrina Harrison said it was not the first time the family had encountered a problem involving Department of Housing property.

"Things need to change at that place, they need to listen to their tenants when they say there is an issue," she said.

"We don't ring up just because we're bored and we've got nothing else to do, we ring up because there are problems.

"We always get told 24 hours or 48 hours [waiting time], and now I'm losing my niece, she's losing her daughter, through something that should never ever have happened.

"It's just so wrong and it's just not fair."

Housing Minister Peter Tinley said his department would do whatever it could to support Denishar's family.

Peter Tinley says the government will find out what went wrong at the house. ( ABC News: Pamela Medlen )

He said an investigation by the Office of Energy Safety would determine what caused the accident.

"One thing I can assure Ms Harrison and everybody interested in this particular tragedy is that we will get to the bottom of it," Mr Tinley said.

"We will find out what has happened [so] we can make sure other West Australians are safe and that this doesn't happen again."

A Perth barrister has said the Woods family could be eligible for millions of dollars in compensation if the Department of Housing is found to have failed to provide them with safe and adequate housing.