Casey Jones posted an interesting video on YouTube regarding a landslide underway affecting over 200 homes in the city of Rancho Palos Verdes in the LA area south of Long Beach.
The short story is that an existing formation with several different layers is shifting roughly south to southwest out from under homes in the area at a rate of about 50 feet per year. In the last few days, a much more accelerated shift took place, destroying many homes and triggering mandatory evacuations of many more. Look at 6:30 in the video for a still photo showing the extent of the shift and its impact on a neighborhood.
Jones notes that this slide may have indirect roots in a road project that cut into the “toe” of the existing layered landslide back in 1956 to expand a road. By cutting into the “toe” (the part of the formation closest to the ocean), it exposed that area to more water, which has helped erode more of the ground underneath, making it easier for the rest of the formation to move larger distances.
The real point of the video was to ask the multi-milliion dollar question. The city of Rancho Palos Verdes has an annual budget of about $35 million dollars. This ongoing landslide and threat of larger landslides has triggered work to create roughly seven bore holes into the formation across the city as a means of extracting some of the lower ground water to essentially remove some of the “lubricant” making it easier for the ground to slide out from its current location. How is a city with an annual budget of $35 million going to pay for $35 million in attempts to mitigate this problem?
More importantly, at what point should a city STOP spending this kind of money to save homes which cannot actually be saved? Should the state of California or the federal goverment step in and provide funds for these mitigation / avoidance efforts? Or should everyone recognize a losing battle and focus on relocating the community?
This particular issue might have been WORSENED by recent heavy rains over the last year from “atmospheric rivers” that could be attributed to climate change. However, the root of this issue might be purely geological in nature. Building a community in the foothills of mountains directly adjacent to an ocean seems guaranteed to produce this situation. Regardless of the cause, the economic and political challenges are identical.
On the Atlantic Coast of the US, if your home falls into the ocean, you’ve lost it, and they won’t let you rebuild. Also, after it floats away, if it gets stuck somewhere and is a threat to navigation, they make you hire a contractor and collect the debris.
Depends on the material you build on or build next to. The granite in Porto is pretty solid yet they still stabilize it when necessary. The biggest headache of a road construction customer in Venezuela was clay which creeps.
It kind of feels like home insurance is going to become a thing that only the very wealthy can afford. And I really can’t blame insurance companies for wanting huge premiums for insuring risks that they cannot predict or model very well. Does not bode well for the mortgage industry either, when home insurance payments start approaching the cost of mortgage payments.
And in the current version of America that hates anything to do with socialism, Cities and States are going to have a really hard time raising taxes in order to rebuild the infrastructure(s) that get wiped out during weather related events.
At age 12 in 1963, on one of my family’s annual visits to Marineland,
and Wayfarers Chapel (paternal grandma being a sometimes Swedenborgian),
I saw and came to understand the local HAZARD: a very HUGE inexorable slow motion landslide! With houses and lots of stuff located on it!! And people pretending they could control it!!! One year we “visited” (hopping a fence) a very optimistic system of drain pipes that were installed there so as to Do Something!
Any willingly sentient creature with a modicum of curiosity, a smidge of skepticism, and especially functioning eyeballs visiting the area over the last fifty years (since enlargement of the roadway across the slide fully exposed the situation) would have seen the same. One member of the relevant city government resigned in outraged protest to zip effect on the electorate/populace who enjoyed the staggering views and prestige while ignoring blatant reality.
I was repetitively astounded that such clear hazards can be and are willfully ignored. Mom and Dad tried to explain WHY to me long ago, making me ever more interested in politics and “dirty handed, wet footed, sliderule slinging” engineering…and human folly.
A great book on this topic is The Control of Nature by John McPhee. There are three sections, trying to control the Mississippi river from changing course, trying to control lava in Iceland, and trying to control landslides in LA.
So, he raises a good question as to who should pay for the wealthiest people in America to sustain their properties in light of a massive land flow. OTOH He suggested that maybe investing money here is wasteful. The same can be said for Houston. Floods cause more property damage in the United States than any other type of natural disaster. There are homes in Harris county that have been rebuilt with FEMA money nine times.
My takeaway is that the wealthiest retirement community in the United States isn’t going anywhere, and slide containment will be paid for one way or another.
Second, I believe that his assessment of home insurance in this community underestimates the number of people with earthquake insurance that covers earth-movement.
Third, if you’re paying $1,200/sqft for homes in the area, I’m sure that Gov. Newsom will take your phone call. If you can afford $5,000/mo HOA fees you can afford a city bond to pay for some of the containment.
I am convinced that the wealthiest retirement community in the United States is going to discover the limits of what can be accomplished with both engineering cunning and political vote-buying, that it will end up going with the flow of its underlying ground, and all moneys spent to stop that will end up being wasted. Only question is how much money will buy how much time?
This situation highlights one of the challenges of climate change. All three points are probably true, if not in Rancho Palos Verdes, then in other locations.
Remove any one and the houses are probably OK. Climate change is a threat magnifier.
As I pointed out, the flooding in parts of Harris County hasn’t stopped FEMI from spending billions continuing to rebuild home in floodplains. There are hundreds of homes on Harris county that have been rebuilt 8 to 10 times with FEMI funds. Palos Verdes is looking a some 40 to 50 homes.
You may be right, but I doubt very much that Palos Verde will be abandoned
Palos Verdes is a peninsula much bigger than Rancho Palos Verdes, and it will NOT be abandoned. Just the part that is slowly falling away will be abandoned (Hey, it’s a landslide!), and that is entirely within RPV.
The scandal of USAian subsidization of housing on flood plains is much larger scale with far more beneficiaries, both small scale idiots buying the ever repeating scam, and the various large scale crooks who approve facilitate finance build and sell to people desperate for housing.
I’m not sure how you distinguish between types of flooding. Whether it be from a hurricane or not, the landslide in Rancho Palos Verdes is due to flooding. The last two years, Rancho Palos Verdes has seen over 52in of rain, and the run off from Rolling Hills, and Portuguese Reserve. The decade before the 2022-23 season saw 80in of rainfall in ten years total.
The same is true in Houston which has seen three 500 year floods in nine years (not trying to pick on Houston in particular). When it comes to floods in Houston there is an ongoing flood damage problem. Homes that are rebuilt repeatedly with taxpayer-backed FEMA flood insurance are referred to as Severe Repetitive Loss Properties, or SRLPs. Harris county leads the nation with 7,700 SRLPs. In total The Houston area has 7,700 SRLPs and has received over a billion dollars in FEMA just for SRLP damage over the years, and according to FEMA 75% of those don’t have any mitigation/alteration to protect against future flooding. FEMA plans to distribute $800 million in Flood Mitigation Assistance grant funding to help reduce or eliminate the risk of repetitive flood damage in Harris County. Not all of that funding will go to Harris county, but Harris county by far has the greatest number of SRLPs.
The landslide in Rancho Palos Verdes is not the only problem, all of Palos Verdes is sliding. The Palos Verdes Peninsula has a history of landslides. According to the WashPost, Rancho Palos Verdes received a $23 million federal grant from the Federal Emergency Management Agency last year. The sudden slide at Portuguese Bend is a small area of Rancho Palos Verdes. It remains to be seen at this point if the Palos Verdes dewatering wells project is a “ship that already sailed” (extract groundwater to stop it from infiltrating the slide).
As far as the phone calls to Gov. Newsom, Governor Gavin Newsom declared a state of emergency in Rancho Palos Verdes Tuesday afternoon. According to the governor’s office, contrary to the YouTube engineer, Newsom’s Office of Emergency Services has been coordinating with city and county officials for nearly a year to support them in responding to the land movement.
Will homes be permanently lost in the major slide area where hundreds of home have been cut off from power and services? Yes, and that is true in all natural disasters. After The Camp Fire in Paradise, California 30% of homes were never rebuilt. Two-thirds of homes burned in CZU Fire never rebuilt 4 years later. Will the Slide Mitigation plan move ahead: absolutely
