Thseng, I have never heard of that! It looks to be the most logical solution... even if they aren't being shot at.

Sue

I wonder how man SoCal residents are relying on their swimming pools as a water source. And I wonder how much would be left in them after the shake?

It would certainly play havoc with the real estate values, wouldn't it?

Sue

The past experience in major quakes in SoCal (Sylmar and Northridge) is that real estate values are depressed for about three months, and then everything gets back to normal. A really large quake, an 8 or 9, might keep values down a bit longer....

Sue and folks ... The various thoughts expressed here were quite helpful. I've been thinking about possible solutions, and I am going to go away for a couple of days and put together a trial "plan" for a fast-response to an earthquake in L.A. Then we can take a look. I wonder if anyone at FEMA ever reads these threads???

Meanwhile ... the Great Shakeout is an attempt by many agencies to get the residents of L.A. "involved" in planning for a major disaster in their own city. You would think that everyone would be highly motivated. BUT several factors tend to undermine preparedness.
(1) People in So. Cal have been told that the Big One is coming for at least the last 40 years. So the typical reaction to this news is "Yeah ... heard it all before".
(2) Like many cities, life in L.A. is incredibly busy and stressful these days. Especially in a never-ending economic recession. So families are just struggling to get by each day, while parents try to avoid getting fired from their jobs and bosses demand that people work longer hours. It's tough.
(3) Even when people do get together some earthquake supplies, the pile of stuff gets "eroded" over a period of weeks or months. Things get moved. Water and food are used for other things. Tools are used for other jobs. And pretty soon your earthquake supplies are mostly gone.

I think I said before - but will repeat again. I asked people here in Los Angeles (where I work) how many days of supplies they had put away for a disaster. This was immediately after the Sendai quake in Japan. My co-workers had enough food & water to last maybe 2-3 days - if they were lucky. Many only had 1 container of water in the cupboard at home. And these are professional people (!). I really doubt that anything has changed, since i asked those questions.

So real preparedness in L.A. remains very low - at least at the level of the civilian population. And most local agencies, like fire and police, do have plans. But they tend to be "responsive" - meaning that they will adjust to the real conditions of the incident AFTER it happens. However, if that incident involves a disaster of Biblical proportions, along with a civilian population that is virtually unprepared, then you know what the end outcome is going to be.

Pete2

I haven't been back to SoCal since I left in 1980, 30 years. I know it's worse than what I remember, and even then, you could almost walk the rooftops from the Pacific Ocean to Redlands without touching the ground.

The idea of a mega quake hitting there is mind-boggling, more than the mind can really comprehend. But I'll bet that most of the people there will be found on their lawn chairs, watching the sky for FEMA helicopters to deliver their cold drinks and hot meals.

And Pete, you're absolutely right about the current day-to-day stresses that are eating away at people. If we don't slide right into a full-scale economic depression, I will be incredibly surprised.

Can you imagine a full-scale depression and then being hit by a mega-quake anywhere in the western U.S.? A zombie apocolypse pales by comparison.

Sue

Not to minimize the consequences of a major earthquake in LA, San Francisco Seattle, Portland, or other large cities. However, one needs to keep in mind that the amount of ground breakage is very dependent on local geologic conditions, which vary dramatically in a small area. Above ground features, such as highway overpasses, are different, in that they can collapes due to the shaking itself. A runway can shake a lot and not be damaged if there isn't actual ground breakage. Certainly the damage in Anchorage from the '64 quake varied tremendously over small distances. Part of my house dates from pre '64, and was not damaged at all, so far as I know. About a quarter mile away, a whole neighborhood was totally destroyed in a landslide.

Regarding airports specifically, the control tower at Anchorage International collapsed. I'm not sure how much damage was done to the runways. I do recall reading somewhere that Elmendorf AFB (just north of downtown) was able to get recon flights into the air the day following the '64 quake, to begin surveying the extent of damage. I will try to find out more info on this.

Beacause they are designed to operate in war zones, military aircraft are a good deal more versatile than many people realize. Besides the big C5A's, there are somewaht smaller C-17's, and smaller still C-130's. Either of these can operate on shorter and rougher strips. If even a portion of the runways (or even taxiways) at SeaTac or LAX were left intact, there is a good chance these aircraft could get in. Bring in a few bulldozers in the initial loads, and even more of the runways might be put back into operation. Helo's would be essential to ferry supplies out from these airports to outlying areas. The military also has mobile teams that could quickly come set up local air traffic control to fill the gap left by destroyed control towers etc.

There is no doubt that a major earthquake under a big city would be catastrophic. And no question that people should prepare, as much as their particular circumstances permit. However, there is also no doubt that some significant help would be coming in from areas outside the damage zone.

A Mullberry harbour might be useful. But they would need to make sure that they don't let it blow away in the wind.

Now those are really cool, but they don't scale up for supplying a major city in rubbles with water and food...

I think shipping is the only way to realistically move the quantities needed for supplying million-size cities when there's no working infrastructure. Most really big cities are at or close to the coast. You still have the problem of distributing withing a city without any working roads, but at least you've got shiploads and shiploads of supplies in the harbour.

Shiploads full of useful supplies along with skilled relief workers, trucks to deliver supplies and heavy machinery to clear the docks and the roads so stuff can get unloaded and the trucks can go anywhere ...... That kind of organization isn't something you just improvise. Just think about the recent big EQ in Haiti and how long it took before heavy-duty relief effort was being shipped in substantial quantities. Pre-planning can cut the response time considerably.

For the city of Los Angeles,the most practical way to deliver supplies inland from the coastline would be by Tsunami.LAPES are not going to cut it for a population over a few thousand,at best!LAPES loaded with fae's or daisycutters would be more of a humanitarian effort in the longrun!

OK, replying to myself now, I did a bit of research after work today. Damage to airports after the '64 Alaska Earthquake was overall surprisingly light. According to Hansen et al (1966, USGS Prof Paper 541, "The Alaska Earthquake March 27, 1964: Field Investigations and Reconstruction Effort"): "Damage to airports was relatively minor....Greatest damage was at Anchorage International Airport, where a life was lost when the control tower collapsed...and where minor damage was sustained by other buildings.....Runways and taxi strips were only slightly damaged."

However, port damage was another matter. The ports of Whittier, Seward, and Valdez were almost totally destroyed by a combination of fires, slumping, locally induced waves due to underwater landslides, and the tsunami generated by the earthquake. The Port of Anchorage (which is not subject to tsunamis) was damaged, though much less severly, by slumping and shaking.

As I noted in my previous post, damage in an earthquake is highly dependent on the local geology of each site (soils, topographical relief, etc). How succeptable a port is to tsumanis is likewise highly dependent on the local underwater topography.