AKSAR

re faults like San Andreas. I thought there was a study done on an undersea fault that ruptured in a way similar to the San Adreas. and generated a quake larger than expected. I'm not claiming that the San Andreas will give a Mag 9. My comment actually said 8-9. So that could include an 8.2

MATH: There are about 10 million people in LA County, and 3 million in Orange County. Let's suppose 50% have serious water problems. so that's about 50% x 13 million = 6.5 million. If each person needs 4 pints of water per day (which is a LOW number!), the requirement is 25 million pints of water PER DAY. Stop and think about how you could possibly get 25 million pints of water per day into a major metropolitan area, esp. with the major freeways down. Helicopters cannot come close to this problem. Even if there are large convoys of Army trucks transporting water on normal roads, it's probably nowhere near 25 million pints per day, and it only reaches some distribution points. THIS is a big problem. I don't see how the math comes close to working out i.e. supply versus demand. I agree that people will drink from ponds, but those will be gone quickly. the quake could damage some reservoirs.

Bottom line - I am not optimistic about how people will behave, once their families are seriously thirsty. It's a real concern, I think!

Pete

I suspect that supplying drinking water to those affected would be well within the capabilities of the civil or military authorities.

A tanker truck holds at least 25,000 litres of water, 100 such trucks each making 10 trips a day can supply 25 million litres a day. In an emergency, such tankers can be hired or requisitioned from dairies, breweries and other industries handling potable liquids in bulk.

Wide bore flexible hose as used by fire fighters can transport a lot of water. A single line of hose with a pump every half mile can transport 10,000 litres an hour, enough for tens of thousands of people.

Providing enough water for firefighting would be more challenging, though the many swimming pools would help.

"A tanker truck holds at least 25,000 litres of water, 100 such trucks each making 10 trips a day can supply 25 million litres a day. In an emergency, such tankers can be hired or requisitioned from dairies, breweries and other industries handling potable liquids in bulk."

As a long-term solution, say within 4-6 weeks after a major quake, I think your idea would be fine. There are a lot of logistics to be figured out. Roads have to get re-built, and debris removed. A large number of trucks, driving constantly, also requires fuel depots. Somebody has to set up distribution points around L.A., and organize how water supplies can be given to victims. All this stuff can be done - but it's a major logistics challenge.

BUT I don't see how any of it happens in the first 2-3 weeks after the quake. There will be a lot of confusion in the city. Many roads broken, or with debris. There could still be fires burning in some neighborhoods. So there won't be any simple logistics paths. The situation really needs someone like the US Marines and the US Army Corp of Engineers working together ... to establish new supply routes. I'm not sure that we have any such plan. So I still think there is a time window, maybe 4-10 days after the quake, when supplies of food and water will be critically low for millions of people in the quake zone. It's possible that California will try and put the city under martial law. But that won't stop people from dying from dehydration.

I think that one of the things that people forget - there are TWO sides to an earthquake fault. There is major damage on both sides. For the San Andreas, on one said you have LA and all the communities. But on the other side you have major towns that are "bedroom communities". The general area of Lancaster-Palmdale now holds over 300,000 people. There will be heavy damage there, and major destruction in Palmdale. The area over by Victorville, with a sprawling population of 100,000 people (incl. Apple Valley) will also see very heavy damage. And looking south down to Palm Springs and Palm Desert, with a population (60,000-100,000 seasonal) - those cities will be wiped off the map. They are sitting at the epicenter for the Southern San Andreas rupture location. So the bottom line is ... there are easily half a million people in the bedroom communities of LA who will be in desperate shape ... and those people are on the OTHER side of the fault line. It would take 2-3 weeks just to stabilize all these people - but that job is do-able because outside access roads are more direct.

Pete

"I'm not sure that we have any such plan." I don't know whether or not there is such a plan, nor do any of us know if there is an effective plan in place which will be properly executed when the time comes. Judging from public statements, I suspect effort has been devoted to planning in this area.


I am just a tad more optimistic than you - not to say there won't be trials and tribulations and definite challenges,along with significant loss of life.

Some of us here in SoCal have stockpiled water and supplies and most of us have water inadvertently stored in hot water heaters and toilet tanks. There are campaigns and PSAs, etc. to raise public awareness and preparedness for EQs - not totally effective, most likely, but still of value.

I am confident we will see a massive response to an incident here, but I agree it will take time. I am good for about three weeks, pretty easily. "72 hours" is better than nothing, but it likely will not be enough.

Hope that you are right about human nature.

What works in the FAVOR of Los Angeles - in a backwards sort of way - is that it's likely that we will get large local quakes (under the city) before the San Andreas ruptures. Those local quakes, while quite devastating (with casualties), will be the best reminder for people to prepare properly. Hopefully the "city quakes" will also be an excellent reminder for the federal disaster response folks - they need a GOOD PLAN for L.A.

Pete

I agree, based on my experiences at multiple disasters. For the most part, a disaster brings out the best in people. Where things like looting occur, it tends to be mostly goal oriented, and targeted at commercial establishments, not people's private homes. The people who are visibly armed usually stick to their own homes and businesses, and they don't tend to bother anybody who isn't bothering them.

I've also noted that it's established blue-collar, working-class neighborhoods where I've seen the most visible neighbor-helping-neighbor activity. I've seen far less of that in wealthy neighborhoods, or places with more transient populations, like apartment complexes.

With respect, my opinion is somewhat different. We MAY be able to supply the water people need, but I suspect that it will severely strain the capacity of available civil and military resources.

There are two major components of the problem. First is making or accessing potable water supplies. Existing civilian water plants in the affected area may be offline for some time, along with their normal distribution grid. Trucked in water will have to come from further away than just outside the affected area, since SoCal is surrounded by a lot of desert. Trucking in all that water will require passable roadways, intact overpasses, etc.

In this case, a saving grace may be that SoCal is rather near the coast. Some USN vessels can make, pump or deliver a lot of water, and commercial ships can also deliver a lot, although offloading may be a problem.

The second major component of the problem will be distribution of water to each and every neighborhood that needs it. Again, roads may be a problem. Also, I expect that Fire Department resources will be tasked with higher priorities than relay pumping drinking water.

It can be accomplished, but it won't be pretty. Let's just hope it happens in a season other than high Summer.

"a saving grace may be that SoCal is rather near the coast. "

I have thought a lot about that too. To be honest, California is NOT doing a lot of things - they should be doing!

Right now CA is in a major water crisis. We know this is not going away any time soon. This should be a time when they take major emergency action to build as many desalination plants as possible. I know they've got studies, and one plant is coming on line soon. BUT honestly. they needs these facilities all the way up the coast. Especially around the big cities. It's a real lifesaver.

I also thought about the US Navy. TRUTH is - they could make a tremendous difference. In terms of security, water supplies, and hospital beds. I don't know what the capabilities of a large aircraft carrier are - in terms of water purification. I've got no idea. But they must be pretty good - just to sustain the operations.

Like I said - if we are "lucky" we will get a local city earthquake that really shakes things up. I am 100% positive that the system can handle a local quake - like the Newport-Inglewood fault line. Or maybe the Palos Verdes fault line - it's the sneaky ones that creep up on you. That fault is active, but has not triggered for a very long time. There could be hundreds of casualties, and the economic damage will be really huge. But it will have the big "payoff" of really giving the LA and California governments a wake up call. That could save a lot of lives over the long term.

I am confident that people will pull together during the first 72 hours after a quake. I am pretty confident that a lot of people will keep trying to be positive for a lot longer. But I don't know what will happen during the time period 3-14 days after the Big One hits L.A. I guess we will find out.

I am a scientist. I live in LA. I went back and personally double-checked all the data for the southern San Andreas fault line. According to my quick calculation, there is a 98% chance that the Big One should have hit already. So right now, we running on a 2% chance that we are still in the clear. Nobody knows how long that 2% is "good for". But seriously, we are "running on fumes". In terms of geological time, this could still be 10 years 0r 30 years. But it could just as easily be next month or the end of the year.

Pete

Pete, thanks for starting this very interesting thread. It has stimulated me to do a bit of research on various earthquake and disaster related items. A couple of points:

Regarding the potential magnitude of strike slip earthquakes, the conventional wisdom has been that they don't get bigger than about M 8. Pete mentioned some recent data suggesting they could be bigger than that. He is probably referring to the 2012 M 8.6 earthquake that struck off the coast of Sumatra. The size of this quake surprised most seismologists. So yes, they can get bigger. However, something in the M 7 range is still probably the most likely case for "the big one" on the Southern San Andreas Fault.

Pete raises the very real issue of supplying potable water to SoCal after a big quake on the San Andreas. As he points out this is not hypothetical nor is it a trivial issue. I found an interesting document from the LA Mayoral Seismic Safety Task Force. The section on water, beginning on page 54 makes interesting reading. The bulk of LA's water comes from 3 aqueducts, all of which cross the San Andreas Fault. The Los Angeles Aqueduct crosses the fault once, in the Elizabeth Tunnel Near Santa Clarita. The other two aqueducts cross it multiple times. All would likely be cut in a major quake, and would take a year or more to repair.

There are some emergency water sources available. The Mayoral report notes "There is an inadequate backup water system available to provide water to Southern California through the one-year aqueduct reconstruction period. Emergency water supplies are stored for use following an earthquake. These supplies are stored at the Stone Canyon, Hollywood, and Encino Reservoirs where large water volumes are stored primarily for emergency purposes. Back-up water sources are also available through connections with other water distribution agencies. Additionally, MWD constructed the large Diamond Valley Reservoir and some local groundwater banks for emergency water storage, some of which can be made available to the City of Los Angeles. Despite these efforts, local water storage is estimated by MWD to last approximately 6 months, and even then only with significant rationing."

Also note that for those area on the east side of the fault, the situation might not be quite so dire. Presumably the portions of the Los Angeles and other aqueducts east of the fault would continue to be operable. Indeed, places like Palmdale might have more water than they know what to do with.

JeffMc was concerned about having to transport water from great distances in a largely desert area. However, if the portion of the aqueducts east of the fault remain intact then it is a somewhat more tractable problem. To be sure there would be great difficulties in distributing the water, especially early on. And it would be a long long time before SoCal was back to normal. However, I think with a large scale mobilization of military and other resources, enough water would reach the people to sustain life.

How well served by railroads is the area ?

Basic repairs to a railway line following earthquake damage are often easier than repairing a freeway for heavy truck traffic.
A single train can transport several million litres of water either in tankers or packaged water in cans or bottles.

Some breweries are equipped, in an emergency, to can drinking water on a vast scale and some dairies can package drinking water in milk jugs. Such firms are well equipped for handling vast numbers of cans, bottles or jugs.
Railroads can transport such supplies economically in bulk over hundreds or even thousands of miles.

Here in the UK the army train in emergency repair of railways, I presume that this is also the case in the USA.