As heavy rainfall drenched Southern California on Wednesday, large concrete planters came crashing down at a shopping mall in Rolling Hills Estates.

Around 60 to 80 feet of dirt-filled planters and flower boxes tumbled over a parking lot entrance at Promenade on the Peninsula around 2 p.m.

A witness, Dana Graham, was sitting in his realty office across the street when he saw the concrete structures collapse.

“I was sitting at my desk and I heard what sounded like a really bad traffic accident,” Graham recalled. “The water was cascading off the top level. It was like Niagara Falls. I’m glad nobody was under it when it collapsed because they wouldn’t be around.”

Mall employees taped off all entrances to the garage as firefighters and structural engineers arrived at the scene to clear debris and assess the damage.

“Essentially, it was excessive water on the planters that were on the facade that caused it to collapse,” explained an L.A. County fire official. “There are other planters in other locations and they are being assessed as well.”

The Rolling Hills Estates community is still recovering from a massive landslide in July that destroyed a dozen homes and forced widespread evacuations. A report released in November claimed excessive rainfall was to blame for the shifting soil and widespread destruction.

With rainfall continuing through the end of the week, residents are concerned the storms will result in even more damage to homes and structures.

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