A crew works on the collapsed hillside on Alvarado Road on Jan. 24, 2023, over a week after the slide. The mud took neighbors by surprise last week. “We heard nothing,” said Sari Cooper, a neighbor, about the river of mud that slid down onto the street. Credit: Ximena Natera, Berkeleyside/CatchLight

The first time Gary and Randi Plotner remember the hill above their house starting to slide, it was spring 2006. It began with a giant crack, debris falling as the land separated from the hillside. 

The hill was deemed at risk of “imminent danger of catastrophic failure.” As it pulled away, it exposed the foundation of the $4.5 million dollar house that had just been built midway up the slope. The Plotners’ house was yellow-tagged, and they evacuated. Several inches of mud coated the road, but the neighborhood on the edge of the Berkeley and Oakland border escaped the worst-case scenario. The three houses sitting directly underneath the steep hill remained largely unscathed. 

The Plotners moved back in. Then, they waited. For nearly 17 years, the hill, almost miraculously, stayed put. Beneath the shadow of the menacing hill, million-dollar views were paired with the threat of natural disaster. 

Geotechnical experts who surveyed the slope in 2006 agreed that rainfall could easily reactivate the slide. Efforts to shore up the hillside would not be completed until fall 2022. 

Just a few months after the crews left the neighborhood came this winter’s drenching rains, and then — last week — another landslide on Alvarado Road coating the street in a river of mud. (This was one of two slides that occurred in the area last week. The other slide near Zaytuna College is ongoing and 14 Berkeley residents remain barred from their homes.)

“It’s kind of a physical manifestation of what anxiety is like,” said Sari Cooper, who has lived two doors up from the Plotners on Alvarado Road since 1999. “There’s always this thing hanging over our heads.” 

Cooper was pregnant with her second child when the first slide occurred. Every year, her son, Ziggy, got a year older, and still the neighbors saw no repairs to the hillside. He’s now 16.

Neighbors say drawn-out legal challenges delayed the work necessary to shore up the hill. “Nobody wanted to take responsibility for it. Meanwhile, those of us at the bottom, we don’t have control over anything,” Randi Plotner said. 

Randi and Gary Plotner photographed at home on Jan. 24, 2023. The Plotners, whose property sits directly underneath the hillside, have been keeping records on the issue dating back 15 years and have led the efforts to organize their neighbors. Credit: Ximena Natera, Berkeleyside/CatchLight

At the heart of the issue is the question of responsibility. 

“What caused the mudslide? Mother Nature? Well, we all know you can’t sue Mother Nature,” Gary Plotner said. But it’s different, he said, “if you can show neglect.” 

Building homes on sharp slopes is known to exacerbate landslide risk — and it gets worse when water is added to soil, whether through landscaping or leaks. Most of the Berkeley-Oakland hills are at some level of risk, but this slope is particularly precarious, rising at least 200 feet straight up at a 60% grade, based on a Google Earth analysis. (Slides are more likely on slopes with grades steeper than 15%.) 

Is the collapse of such a steep hill inevitable or is someone to blame? And on roads like Alvarado, a key evacuation route for Oakland and Berkeley residents, what’s the city’s responsibility for preventing a slide?

It took time to hash out these questions after the 2006 slide. 

James G. Potter, who owns the Provençal castle atop the hill at 21 Drury Court, ended up spending over $2 million — much coming from insurance — constructing a massive retaining wall 60 feet deep that runs the length of the property and adding tie-backs that go 150 feet into the hill. Y&H, a San Francisco company that owns the hill beneath Potter’s home, also did work to shore up its property, primarily by compacting the soil.

Potter said there was a multi-party lawsuit that ended in a 2012 settlement and involved multiple insurance agencies, Y&H and his home’s architect and developer, Ronnie Rogers. (Berkeleyside has not been able to independently review the lawsuit. Rogers told Berkeleyside he didn’t remember anything about a lawsuit and declined to comment further for this story. Voicemails left with phone numbers associated with Y&H went unreturned.)

Gary Plotner shovels mud off of Alvarado Road Monday morning after the slide. Credit: Randi Plotner
Crews work to add temporary piping and prevent the land from sliding further down. Credit: Randi Plotner

According to Potter, the massive expense seems to have paid off. Neither his home, nor the land below it, budged after the latest storms, he said. 

But the new mudslide, which appears to have begun just east of the earlier slide, will reactivate a similar set of thorny questions of responsibility. Y&H owns the hillside, and Rogers built Potter’s next-door neighbor’s home above it.

Waiting to see how it all shakes out, yet again, are the neighbors down the hill.

A ‘castle’ nestled into a steep slope

A view of the mansion owned by James Potter, the work done to shore up the hill below, and result of the landslide on the left. Below, three houses on Alvarado Road sit directly underneath the hill. Last week’s landslide occurred beneath Potter’s neighbor’s home (not pictured) — built by the same developer. Credit: Ximena Natera, Berkeleyside/CatchLight

The Berkeley and Oakland Hills have long been susceptible to slides, especially during earthquakes and after periods of heavy rainfall. Throughout the 1900s, slides threatened livestock and livelihoods. In 1982, a house on Alvarado Road half a mile away from the most recent slide was crushed.

Despite the risk of landslides, Rogers decided in the early 2000s to build his dream house midway up the slope, a 7,200-square-foot castle-like mansion with centuries-old chandeliers imported from France.

The city of Oakland approved the project in 2002. In a geotechnical analysis, an engineer assessed the risks posed by earlier slides nearby and concluded that construction would not destabilize the slope. “The Building Services Division is satisfied that the proposal properly addresses landslide concerns,” city staff wrote.

But two weeks after Potter and his wife moved in a few years later, the ground started to slide out from under them.

Fast forward 17 years and Potter is watching his neighbors face similar problems. While his land has held fast during this winter’s rainstorms, the land directly east of his house wasn’t shored up at the same time as Potter’s was. Now, it appears to the neighbors living below, that was the part of the hillside that fell last week, sliding down over a rocky gully that was part of the landslide prevention work.

For both slides, questions about why the hill slid and whether something could have been done about it remain unresolved. “Each geotech kind of says, ‘Well, it could be this or it could be that without any definitive determination, then that leads to a group settlement,’” Potter said. 

The neighborhood grapevine has its own answers. Though they can’t know for sure, they believe it could have something to do with a sewage pipe on a portion of the hillside owned by 11 Drury, another house built by Rogers.

In September 2021, Potter’s attorneys sent a letter to city of Oakland and EBMUD officials alleging that an illegal private sewer pipe under 11 Drury “ruptures periodically expelling raw sewage … threatening the long-term viability of a multi-million-dollar hill repair above Alvarado Road and Gypsy Lane.” 

Attorneys representing the former owners of 11 Drury denied the sewage line was illegal. They said it was code compliant and that it wasn’t defective.

‘A watchful, protective eye’

A crew worker points up the hill. On Alvarado Road in the Claremont Hills, neighbors have lived with the threat of landslides for decades. Credit: Ximena Natera, Berkeleyside/CatchLight

Last Thursday, Randi Plotner flipped through a thick three-ring binder containing all the records she had saved in the 15 years that followed the slide, documenting her and her neighbors’ efforts to protect their homes. 

They included Oakland’s original permit for the construction of Potter’s house, emails sent in frustration to local officials and attorneys and much more. “In some cases, we had to scream a lot,” Plotner said, summarizing years of advocacy.

Now, after the latest slide, she has kicked into high gear.

“We’re in for some difficult times,” Plotner said knowingly, anticipating the work involved in protecting their homes.

Over the weekend, she held a small neighborhood meeting to discuss what had to be done to mitigate future risks. Shivani Grover, a member of the North Hills Community Association, also visited the neighborhood last week, as did employees from the city of Oakland’s transportation department. 

“There have been so many slides on Alvarado Road before. The area is prone to that,” said Grover. “The city should take a more watchful, proactive eye on those areas.” 

What role local governments can or should have in preparing private property to better withstand natural disasters is complicated. 

A 2006 Oakland City Council decision to spend $300,000 preventing erosion that could lead to another landslide on the Alvarado Road hillside was controversial, raising concerns that it would set a precedent for using public funds to improve private land.

But Janani Ramachandran, the newly elected Oakland council member representing District 4, expressed interest in working around the challenges and promised broadly to focus on long-term planning to prepare for future disasters. 

“We do need to start being more proactive, rather than reactive,” Ramachandran said. “I want to take it upon myself to advocate for the funding, whether it’s county or state level, to build infrastructure that we need to prevent these issues from occurring.”

Though the city cleared the mud that piled up on Alvarado Road within the first six hours of last week’s slide, the hillside continued to slowly move down the slope. Soon, more mud was blocking a sewage drain at the bottom of the hill. Crews reappeared, clearing the new mud. A week later, workers were climbing on the hillside, planning to cover it in plastic tarping.

In 2006, Sari Cooper was pregnant with her second child when the previous landslide occurred on Alvarado Road. Her son, Ziggy, is now 16. Credit: Ximena Natera, Berkeleyside/CatchLight

“It sounds so logical that you would just move,” Cooper said, sitting in her kitchen, the mudslide visible in the window behind her. But within days of evacuating, Cooper grew homesick for the house she raised her children in. 

From what they can tell, the hill has stopped moving and a relative sense of safety has come over the neighborhood.   

“It’s happened. It’s working through the process, whatever that is. Until then, everything is a speculation,” Gary Plotner said. Though there is, of course, “this issue that’s always underlying what you might want to do long-term.” 

As for Randi Plotner, she is preparing for a long haul. Motioning to her green binder with old records, she said, “it’s time to start a new one.”

Ally Markovich, who covers the school beat for Berkeleyside, is a former high school English teacher. Her work has appeared in The Oaklandside, The New York Times, Huffington Post and Washington Post,...