They're getting closer to the answer of how this all started. They hope drilling on Wednesday will reveal just how much water is underground and how it got there.
It's been nearly a week since Ronald Martell's dream home was demolished. He's confident what caused the sliding hillside.
"The root cause is the water main as it certainly appears to be," he said.
Crews starting to drill, examine how much water flowed underneath that led 2home being demolished pic.twitter.com/ZPgPz5OLiz— Janet O (@JanetONews) February 3, 2016
He's just waiting for the confirmation once crews start drilling. They'll insert casings that will act as a well to allow them to pump water out and also determine how much water is underground and at what level the water came in.
"The water unfortunately made its way directly onto my property and then the adjacent properties and the properties downhill," said Martell.
Martell estimates the water main leaked millions of gallons of water. The San Francisco Public Utilities Commission shut off the water main on Saturday and since then, Martell says the hillside has been rapidly drying.
"While we lost my home hopefully save other homes around us," he said.
WATCH VIDEO: Crews demolish SF house sliding off hill
Neighbors who have been watching this unfold from day one are still puzzled why no one knew there was a problem before.
"Of course it's a surprise, you don't expect this," said one neighbor.
SFPUC tells ABC7 News that if they are responsible, they will take full financial responsibility.
Martell says he's consulted with a team of experts who tell him he'll most likely be able to rebuild his home on this site.
Homeowner said it was his dream house . Family planned to do renovations . He will figure out if he can rebuild pic.twitter.com/muQdncmuA0— Janet O (@JanetONews) January 29, 2016
SF Public Utilities: No leaks they are aware of along Casitas Ave. Checked cistern and it's full. Water main ok. Root of problem unknown.— ElissaABC7 (@ElissaABC7) January 30, 2016
Crews expect to be here all day tore through first floor two more down below to demolish pic.twitter.com/2z4XAcGDh9— Janet O (@JanetONews) January 29, 2016