A retaining wall in a Black Mountain subdivision collapsed causing one house to be evacuated and another to be placed on evacuation alert.

The incident occurred early Wednesday morning and neighbours described hearing a loud crash that sounded like an earthquake.

The wall extends along Samurai Court on four tiered levels along the steep hill along the backyard of homes that front Nishi Court.

James Kay, City of Kelowna development engineering manager, said cleanup efforts to remove the debris from Samurai Court will begin when it’s deemed safe to do so.

As well, a forensic investigation is underway involving the city’s building and development engineer staff to determine what exactly caused the structure to collapse.

“If the wall was built properly to begin with, what goetechnical engineers tell us why these things happen because something changed. It could be extra loading caused by a structure built above the wall or a change in groundwater flow,” Kay said.

“But we will absolutely want to know what happened in going forward.”

All four walls disintegrated behind the house at 1317 Nishi Crt., which was ordered evacuated by the city. The neighbouring house at 1303 Nishi was placed on evacuation alert, although police at the scene said the residents appear to be out of town.

“I better go home and check my home insurance,” said one resident looking over the damaged walls, the collapsed brickwork spreading out on Samurai Court.

Kay said once the safety factor is addressed, it will take about a day to clean up the street, with much of the fill material, gravel and bricks reusable in the eventual reconstruct.

He said the subdivision developer built the wall initially before many of the homes above it were built. While the wall structure extends up the north side of the entire street, it falls under the responsibility and ownership of each property owner that it crosses.

“We appreciate the patience of people affected. We’ve been in contact with the homeowner who had to be evacauted but otherwise we haven’t had many calls about this as far as I know, which has surprised me a bit,” Kay said. “Once it is safe to do so, we should have the street cleaned up within a day.”

Residents living above the accident site on Samurai Court have had to park their vehicles at the bottom of the steep incline road off Loseth Drive and walk up to their houses.

Nearby, a Nishi Court home, a five bedroom 3,253 square-foot house with a secondary suite near the wall collapse site, is currently for sale with a listed sale price of $799,000, and a second home at the corner of Nishi and Loseth just went on the market this week.

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