With the help of two pumps, 40,000 square feet of plastic sheeting and 250,000 pounds of gravel, officials said they are planning to work 24 hours a day through the upcoming rainy weekend in hopes of protecting property at the site of the American Beauty/Trestles development landslide.
On Wednesday, employees of Landscape Development Inc., the private firm hired by the two homeowners associations that have shared ownership of the collapsing hillside, were blanketing it with spool after spool of tarp, and bag after bag of gravel.
After a weekend storm earlier this month, residents of the hillside neighborhood on the 19700 block of Terri Drive watched as their property physically transformed and broke apart, and the first layer of tarp was laid down to reinforce the hillside. And now, 10 days after families first noticed fissures appearing in their walls and patios, another series of storms is on the way.
“What we did (Wednesday) was in preparation for the rain that’s coming,” said Amy Ambrose, division president for Landscape Development. “We added additional layers of plastic in order to prevent as much moisture from getting into the soil as possible … And our emergency storm crews have begun their 24/7 monitoring.”
However, according to Ambrose, the tarp-and-bag tactic is only designed to be a temporary solution to the expected weather conditions, and more permanent solutions would need to be implemented eventually in order to the address the hillside’s long-term problem.
“If enough water gets into the soil, it creates more movement, which is already happening. And we’re trying to avoid that,” Ambrose said. Right now “we can only try to slow (the slippage), but we can’t fully stop it with what we’re doing.”
Ambrose said one of the primary reasons the geologists and engineers haven’t been able to stop the gradually occurring landslide is because a single mistake made due to misinformation could exacerbate the soil displacement.
“The ultimate plan is to stop it,” said Ambrose. “But there could be something like five different factors going into this and without knowing the source (of the landslide) you could end up making it worse.”
In the meantime, Landscape Development has laid down the initial plastic layer, an additional layer and has a couple extra thousand square feet of tarp and couple extra thousand pounds of gravel waiting in reserve just in case, according to Ambrose.
As for the company’s 24/7 emergency storm crews, when they’re not working with the reserve pile to patch up or fix holes in the protective tarp, they’ll be working on the drainage system or manning the “sump-pumps” located at the top of the hill.
“The rainwater can collect on top of the tarp, and like a cup that gets heavier when you pour a liquid into it,” the water pools on the plastic sheeting and could gain enough weight to cause damage, said Ambrose. “The goal of the two pumps is that we don’t want to retain any water, and we want to pump it out right away.”
The bags will work as a “paperweight” of sorts for the tarp, and although everyone calls them “sandbags” they’re actually filled with gravel, and there’s a reason, according to Ambrose.
“The gravel filters water through, but filters sediment out,” said the division president. “When you try (erosion control) with sand in the sandbags, you’re stopping the water from flowing out … and that’s when you get a thing we call a ‘blowout.’”
Barring any incidents with the drainage system, pumps and/or tarps, Ambrose and her on-site storm emergency crews say they hope to achieve their two highest priorities this weekend: “Slow the movement on the slope as much as we can and minimize as much damage to structures as we can,” Ambrose said.
As of Wednesday afternoon, two American Beauty homes and three Trestles homes, for a total of five houses, have received “yellow tags,” or voluntary evacuation notices, from the city of Santa Clarita. Ambrose said there are a few others, though, that are in danger and/or already seeing signs of damage.
Homeowners Associations and City Hall
G.M. Management Inc., the company contracted with the American Beauty Classics I Owners Association to manage the maintenance and landscaping of the neighborhood at the top of the hill, released a statement Tuesday, saying they were addressing the situation since the first report and are taking it very seriously.
“The association has engaged professional consultants to determine the cause of the slope failure and the necessary measures which are necessary to ‘shore up’ the area while decisions are being made about permanent repairs,” the statement read. “In the interim, the association is providing regular updates to the four homes adjacent to the slope to provide information on the actions being taken by the association.”
Property Management Professionals, the private firm similarly hired but for the Trestles development at the base of the hill, has also commissioned its own geotechnical report. However, as of Wednesday afternoon, residents in the PMP neighborhood report they have not heard from their association or received any updates.
And, as the two homeowners associations announced they were each either hiring or working with their own geotechnical firm to compile a report on the source of the landslide, Santa Clarita City Hall officials said city staff would be on site every day monitoring the geologists and overlooking the safety of residents whose homes were in danger.
“I was out there yesterday with staff from Public Works to see it for myself and get a better idea of the neighborhood affected,” City Communications Manager Carrie Lujan said on Wednesday.
However, city officials, as of Wednesday, were still saying that they and the city engineers will not be heading up their own study, nor will they take on the responsibility of funding or heading up the geological disaster relief effort.
Saying the hillside maintenance was the responsibility of the homeowners associations and developer, Lujan also stated the city had not received requests for assistance from any of the residents or either HOA.
“We have not had any requests for additional assistance in regards to the rain … (and) to my knowledge we have not had any requests for assistance from the families,” said Lujan. “Our staff would work with the consultants on site if they were to recommend additional homes to be tagged.”
A call was placed to the city of Santa Clarita Engineering Services Department Wednesday, but department staff declined to comment and deferred all requests for comment to Lujan. A call was placed to the city of Santa Clarita Building and Safety department and Assistant City Engineer Shannon Pickett, as well, but department staff had not returned the call as of Wednesday.