A Black Saturday bushfire victim has broken down in court, recalling the moment he realised his wife and children had perished in the Kilmore East blaze.

Darrin Gibson lost his partner Lesley and his three children, Kiona, four, Jye, three, and Ava, two, when the blaze hit their Kinglake West home on February 7, 2009.

He sustained burns to 25 per cent of his body and has had partial amputation of both his feet, which had melted off.

In the Victorian Supreme Court on Monday, Mr Gibson said he had been listening to the radio all day on Black Saturday, as well as monitoring the television and checking the Bureau of Meteorology website.

His family had planned to leave in the event of a bushfire but by the time news of the Kinglake West blaze was reported on radio, the fire front was just 200 metres from his home, he said.

Mr Gibson said he called police to ask which direction he could take his family to escape but was told the roads were closed and they would have to stay put.

He lay with his family on the floor of their home until the flames came inside.

He then led his family outside - but there was nowhere to go.

"I told (Lesley) to get to the dam," Mr Gibson said.

"I looked across and she was sitting on the ground.

"She was cuddling Kiona and she said 'I can't move'."

Mr Gibson said he too had become exhausted.

He kept dropping the other two children, and decided to leave Jye on the ground while he threw Ava into the dam.

He returned for Jye but couldn't find him, so he ran back to the dam and Ava.

"She had her eyes closed and her belly was burnt and she just mumbled 'mum', she kept mumbling 'mum'," Mr Gibson said.

"I was calling out for Lesley and the kids to see if they were still alive.

"I knew that they had passed away."

Mr Gibson was placed in an induced coma for four weeks.

He awoke to find Ava had died two days after the blaze.

Mr Gibson is one of 10,000 people in a class action claiming damages against power company SPI Electricity for failing to maintain their power lines, which sparked the blaze.

They are also suing the police, CFA and environment department for failing to give adequate warnings about the fire.