SAN FRANCISCO (KRON) — While crews work quickly to demolish a $2 million hillside home in danger of collapsing, nearby residents say a number of recent construction projects may be causing their neighborhood to slip.
Workers were continuing emergency demolition on the three-story home located at 256 Casitas Avenue. So far, only the top floor has been cleared, and despite inclement weather expected this weekend, workers expect the house to be completely demolished by Monday.
The owners of the 3,143 square foot home were away on vacation when a neighbor reported a massive crack on the side of the house. The structure also appeared to be shifting to one side.
City officials quickly red-tagged the property and ordered an emergency demolition. There were concerns that the home could collapse and fall onto a row of homes at the bottom of the hill.
While engineers investigate the cause of the sliding foundation, city officials have asked neighbors along Casitas Avenue and Miraloma Drive to inspect their homes and report their findings by Monday. Officials will review the reports and decide whether those homes should also be red-tagged.
Joe Cassidy, the contractor who is demolishing the home on 256 Casitas Avenue, has concerns about an adjacent house showing cracks.
“The house at 250 right now, has an issue as well,” said Cassidy.
“There is something happening up here,” he said about the Sherwood Forest neighborhood.
Cassidy doesn’t know what is causing the earth to slide but he says there are signs of movement underneath the road and sidewalks, and out towards the houses.
“The soil is obviously moving under this whole area,” Cassidy said. “It’s maybe groundwater or maybe it’s city water, but it has to be investigated and found out.”
Stephen Ader, a resident on Casitas Avenue, says the neighborhood, which sits at the base of Mt. Davidson Park, is having his home inspected. He says he’s confident his home is not in danger but wants to know what is happening underground.
“We would like to know the real cause of this,” Ader says.
He says the soil movement could be linked to the recent construction work in their neighborhood. In the last year, there was the removal of several large trees during the city’s storm preparations. Pacific Gas & Electric also had to excavate parts of the street to install a high-pressure gas pipelines that runs down Casitas Avenue.
Just up the street from Ader’s home, the city installed a 70,000 underground water tank used used by firefighters last spring. The cistern is massive and buried at least a couple of stories deep, but is seismically fortified, he says.
“There have been El Nino storms, there have been multiple deluges for the last 45 years, and none of these houses have had such a problem and now suddenly one is going down the hill,” Ader says.
“That’s an indicator of something different that wasn’t there before.”