Click photo to enlarge
Developer Joe Callahan (left) and engineer Frank Berlogar survey the efforts to repair a landslide which occurred above grading work for the Garin Vista subdivision being built near Mission and Tennyson Rd in Hayward. October 1st 2007. (Mike Lucia/Daily Review)
HAYWARD — On a South Hayward hillside scarred by generations of quarry work, a 6-acre landslide has complicated plans to build a new neighborhood.

Last year, prominent East Bay developers Joe Callahan and Jack Smith were gleeful about Garin Vista, their proposed hillside subdivision that would afford future residents a panoramic view of the San Jose, Oakland and San Francisco skylines.

Now, they are fighting furiously to stabilize the damaged slope, chopping off an 80-foot-deep section of hillside before the coming rainy season sends it slipping away. The deepest part of the slide is 140 feet deep, Callahan said.

"About May 7, as we're cutting up the hill, we experienced what can only be called a bulge in the midslope of the grading area," said Callahan, poring over a map and describing how "this whole mass, which is approximately 1.8 million cubic yards, has moved down the hill."

The landslide, known as a slump, came as an unpleasant surprise to the developers as they were about halfway through their regular cut-and-fill work, and it has jeopardized the economic feasibility of their project, they said. Callahan estimates it will cost up to $7 million to fix, and that is compounded by the problems caused by a poor housing market.

"It's gone through the sky. We really don't have a hold on it," said Smith, who was Hayward's mayor in the late 1960s.


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"I'm no longer thinking of profit."

For neighbors, the slide also presents concerns. On the west side of the hill, the slide already has encroached into more than an acre of Garin Park, owned by the East Bay Regional Park District. It has affected the parking lot of a nearby apartment complex.

And it has frustrated residents of Bodega Street, who complain of the daily din of a Ride of the Valkyries-style fleet of earth-moving vehicles.

A chain of eight to 12 of the 170-ton scrapers rumbles up and down the slope every day, tasked with emergency grading that will haul hundreds of thousands of cubic yards of soil off the hill by mid-October.

History of slides

For those who know Garin Vista by its old name, Blue Hill, the slide has not come as such a surprise. For one thing, the foot of the hill also marks the main trace of the Hayward fault.

"We were told when we moved in here almost 40 years ago that they'd never be able to build on that hill because it's unstable, it would slide," said neighbor Sharon Golden. "And during rainy seasons, it did slide."

Adelaide Moita, an 80-year-old Bodega Street resident who has lived beside the hill her entire life, said men have been tampering with the slope since before she was born.

The first one, according to local legend, was the Rev. Agapius Honcharenko, a fugitive Ukrainian anarchist and priest who established a 19th-century commune in the Hayward hills. The priest hoped he could find diamonds in the hill's bluish slate, Moita said.

"That was the rumor," she said. "I've heard it ever since I was little. I don't think he ever found any diamonds in it, though."

Next, for sure, came the quarry developers. The bulk of the boring happened at neighboring La Vista Quarry, whose dark, chiseled scars can still be seen from the opposite side of San Francisco Bay.

But inexperienced quarry workers also dug into Blue Hill, at a time before there were strict regulations on how to work the land for materials. Smith, who has family connections to the property dating back to the 19th century, said the quarry operations were haphazard and ended by the early 1950s.

"They just took the materials from the best areas there were," he said.

Smith has pledged over the years that the developments will improve, not worsen, the land by smoothing over the property's scars.

He said he still believes that's the case, but the developers and engineering partner Frank Berlogar did not foresee how deep into the earth the problems were. They didn't drill deep enough to find a dangerous layer of loose, granular material, they said.

"We missed the bad material by about 20 to 30 feet," Smith said. "We drilled 100-foot holes. If we drilled further, we would have known."

Another firm, Dublin-based DeSilva Gates, won city approval in 2005 to turn the La Vista Quarry into a 179-home subdivision. At the time, the same company was working to transform its steep-sided Leona Quarry in Oakland into a housing development, along with other quarries throughout the Bay Area.

That was followed in February 2006 by the Hayward City Council's split 5-2 vote to allow Smith's company to build another 125 homes at the Garin Vista site, just to the south. Current plans would link both developments with a new eastward extension of Tennyson Road that would loop back to Alquire Parkway.

But the La Vista project is largely on hold because of the problems with its neighbor, although Callahan said the poor housing market means that no one is in a big hurry anymore.

DeSilva is supplying the scrapers that Garin Vista developers are using to repair their slide. All of that excess dirt is dumped into a gully at the foot of the La Vista property that is designated by city leaders for a future public park.

Callahan said the park was not intended to have all that extra soil, but he insists the altered grading won't affect its viability — the park would be the same size, just a little bit higher above sea level.

And although the hills are marked by several large green veins of asbestos-bearing serpentine, Callahan said all of the hauled material will be carefully capped according to environmental regulations.

Bob Bauman, Hayward's public works director, said city officials have been monitoring the landslide since it happened. Engineers worked with Garin Vista developers over the summer to formulate a testing regimen and repair plan that both city officials and developers could agree with.

A troublesome rock layer

The slump slide occurred because the underground gravelly layer of rock that developers didn't know about moved down the slope plane. A fissure ripped through the upper end of the hill, and a bulging mass of rock rests at the bottom.

Callahan said he is not sure if it is water-related, but the hills do often have seeps in them and water can fall from a much higher point, finding a soft spot, he said.

Slides are not uncommon in the East Bay hills, said Roland Burgmann, a geology professor at the University of California, Berkeley, and there is always an "unknown factor" when anyone seeks to grade a steep slope.

"If it's not strong bedrock, and you have a slope greater than the angle of repose, then effectively it's a sandpile," Burgmann said. "If you have a big pile of sand, then the hill will want to keep sliding down until it gets to that angle of repose."

City Councilman Olden Henson, who lives nearby and expressed enthusiasm about Garin Vista in 2006, said the incident might be a "telling point" that causes the city to "close the door on future development" in such areas.

His own subdivision has one unoccupied house because of a drainage-related slide several years ago, he said.

And Moita said that in the 1960s, a poorly managed subdivision project on today's Woodland Avenue caused a major slide that threatened her street.

"They cut the slope. There was water coming out of three places, and so the slope gave in and the water came around the road," she said. "They had a one-to-one slope and it was like 30 feet deep, straight up and down, practically. That was their fault."

She said she remembers going to Smith, who was mayor or councilman at the time, and being told the city couldn't do anything about it.

Today, Smith said he is committed to solving the neighborhood's latest land problems. He said that although it might come at a great cost to him, the end product might be a better development, with bigger lots and better views because of the smoother slope.

"We're not going to leave it, we're going to fix it," Callahan added. "We have an obligation to make this safe, and we're going to damn well do that."

Matt O'Brien can be reached at 510-293-2473 or mattobrien@dailyreviewonline.com.