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View Full Version : A Major Earthquake Could Flood the DLR?!?



mckygirl99
11-18-2008, 05:47 PM
So last week when we did the "Great Shakeout" drill at the school I teach at, which is a hop, skip & a jump from DL, I found out some frightening information. We were told by the preparedness staff that if the Prado Dam breaks, Anaheim will be under 7 feet of water because of the way it sits! :eek: Has anyone else heard about this? I wonder if the resort has any type of precautions it would take if something like this happened.

I am pretty scared because not only do I not know how to swim but I am responsible for the 11 children in my class. I thought that dam was pretty far away but it is closer than I thought.

It is just something to think about though!

foolishmortal
11-18-2008, 05:51 PM
The Padro Dam should be just fine even in a major earthquake. I wouldn't worry too much. IT survived the North ridge quake just fine.

I would learn how to swim though, it is a valuable skill and you never know when it will come in handy, and you are NEVER too old to learn how!;)

I'll ask my dad's neighbor about it, his firm did dam consulting for SF a few years back.

screamin4ever
11-18-2008, 06:00 PM
Well I guess anything is possible. But I wouldn't lose any sleep over it. 35 people a year die from lawnmowers but I will still mow my lawn.

cstephens
11-18-2008, 06:31 PM
In the event of an earthquake that can break the dam, having DLR being flooded is going to be pretty low on most people's list of problems. You'd have to have something like a magnitude 9 or 10, and in that case, everything is going to crumble.

"Major" is a relative term.

jenniebean
11-18-2008, 07:13 PM
As if I weren't paranoid enough already... :rolleyes:

currence
11-18-2008, 07:58 PM
It doesn't take a major earthquake to flood Disneyland. Does anyone else remember the El Nino rains in the late 90's?

We went to Disneyland despite the downpour and had a blast walking on to just about everything. We did Space Mountain about 13 times in a row - they were using the wheelchair entrance as the main entrance so you could keep getting back in line without going outside - until part of the roof started leaking and the ride was shut down. We left that ride and found the people in what's now the HISTA theater being evacuated becuase that attraction was flooded.

Then we went on Mr. Toad's Wild Ride (to warm up/dry off during hell) a bunch of times - sometimes not having to get out of the car - until an inspector found water on the track and that ride was shut down.

By then we were weren't sure if anything was still open and ready to leave ourselves. We discovered that Main Street was flooded. Literally water up over the curb in spots and into the entrances of some of the shops. We waded across Main Street (because I wanted to see the shops on the other side) and were given free coffee at the Kitchen store because the power was out, they couldn't sell it, and didn't want it to get cold.

It was one of those trips that was pretty miserable at the time but a really good memory in hindsight.

adriennek
11-18-2008, 07:59 PM
So last week when we did the "Great Shakeout" drill at the school I teach at, which is a hop, skip & a jump from DL, I found out some frightening information. We were told by the preparedness staff that if the Prado Dam breaks, Anaheim will be under 7 feet of water because of the way it sits!

Is this based on the specifications for the "Old" Prado Dam or the totally wow and snazzy and been working on it forever "New and Improved" Prado Dam?

Adrienne

SteveMartin
11-19-2008, 06:02 AM
Is there any significant water behind Prado dam right now?

ladodgerjon
11-19-2008, 07:19 AM
I've been going to the DLR since the 1960s, and was born in L.A.


If a truly MAJOR quake were to hit, there are also issues of "liquification." In short, underground water tables would be shaken, causing the water to rise, and turn the surface into mud. Generally speaking, a quake in the 6.5-7.0 range could create this environment. PARTS of the OC have soft, sandy, expansive soil-- the perfect landscape for liquification.

What I've just written is fact... but not likely to happen but once in every 200 lifetimes. A 6.5-7.0 shaker happens rarely (but IS expected sometime in the next 50 years).

As for flooding, visit Disneyland on a day when we get 1.5 inches of rain-- a flooded Main Street is quite a sight (drainage is a real bugaboo over by West Street).

Malcon10t
11-19-2008, 07:29 AM
Our town is about 30 miles from the local dam. I can remember growing up and everyone's fear that if the dam broke, the town would be under several feet of water. It terrified me as a child. Now, I realize how silly it is. About 10 years ago, we had too heavy of a snow pack, and they opened the dam, giving us a feeling of what it would be like if the dam broke. Town didn't flood. Some houses along the river didn't do well (they did flood) but nothing like the wall of water rushing out of the mountains that terrified me when I was young.

If the earthquake breaks the dam, there is a lot worse things to be worrying about other than DIsneyland.

Katlovett
11-19-2008, 08:01 AM
Our town is about 30 miles from the local dam. I can remember growing up and everyone's fear that if the dam broke, the town would be under several feet of water. It terrified me as a child. Now, I realize how silly it is. About 10 years ago, we had too heavy of a snow pack, and they opened the dam, giving us a feeling of what it would be like if the dam broke. Town didn't flood. Some houses along the river didn't do well (they did flood) but nothing like the wall of water rushing out of the mountains that terrified me when I was young.

If the earthquake breaks the dam, there is a lot worse things to be worrying about other than DIsneyland.
It's much more dramatic in the movies and on TV, isn't it? They always show a 1000 foot tall wall of water bearing down on the unsuspecting city.

Malcon10t, remember the heavy January/February rains back in 1998 (I think it was), when the national news showed flooded parts of Sacramento? I lived there back then and my family members in other parts of the country all called me to see if I was OK. They were pretty sure the entire city was underwater, not realizing that the only flooded areas were places where leaves had clogged the storm drains.

stan4d_steph
11-19-2008, 08:59 AM
If a truly MAJOR quake were to hit, there are also issues of "liquification."The word is actually liquefaction.

DizneyMommy
11-19-2008, 09:53 AM
Eh - just climb the matterhorn or space mountain and wait at the top for the rescue choppers :-)

SteveMartin
11-19-2008, 09:57 AM
Eh - just climb the matterhorn or space mountain and wait at the top for the rescue choppers :-)

If it gets really bad, you can just kill and eat the yeti.

:)

adriennek
11-19-2008, 10:00 AM
Is there any significant water behind Prado dam right now?

I don't know.

A few years ago, there was a big storm that flooded the Santa Ana River area behind "old" Prado Dam. There weren't any homes that were threatened but there were bridges over the Santa Ana that were flooded over and other streets that had to be closed which made a transportation mess for people who use those routes regularly.

The neighborhood below the dam in the western most tip of Corona, the one that most recently lost homes at the beginning of the Freeway Complex Fire, was evacuated because they were worried that the "old" Prado Dam could not handle the water and they could not divert it because they were still working on building the "New" portion of the dam.

I can't quite imagine the dam holding back THAT much such that Disneyland would be under 7 feet though.

Adrienne

SteveMartin
11-19-2008, 11:10 AM
I've been around the other side of it a few times recently and it looks like it's just a big depression with a bunch of trees growing inside. There must be some water behind it as it seems there is always a group of people fishing in the outflow area (yuck!). Right at the 71/91 interchange.

Klutch
11-19-2008, 01:07 PM
Is this based on the specifications for the "Old" Prado Dam or the totally wow and snazzy and been working on it forever "New and Improved" Prado Dam?

Adrienne

Was ithe Old Prado Dam which had the Stars and Stripes painted on it for the Bicentennial? (I'm not specifically asking you, Adrienne. I know you're way too young to remember. ;) )

SteveMartin
11-19-2008, 04:13 PM
Was ithe Old Prado Dam which had the Stars and Stripes painted on it for the Bicentennial? (I'm not specifically asking you, Adrienne. I know you're way too young to remember. ;) )

Yes, that's the one.

ryanvalle
11-19-2008, 09:44 PM
Eh - just climb the matterhorn or space mountain and wait at the top for the rescue choppers :-)

I'd just take a jump into a submarine or a Grizzly River Rapids Raft.

foolishmortal
11-19-2008, 10:24 PM
it's not the wall of water that gets you it's the amount of debris that it is carrying and mud that is the major danger.

Interesting the History channel had a Mega Disasters show on a dam the collapsed in Ca in I think the 20's? Will have to do some research on that.

adriennek
11-19-2008, 10:39 PM
Was ithe Old Prado Dam which had the Stars and Stripes painted on it for the Bicentennial? (I'm not specifically asking you, Adrienne. I know you're way too young to remember. ;) )

Unfortunately, I'm not. ;) (That and they never painted over it so it's just been fading for years.) But like SteveMartin said, yep, that's the one.

Here's a picture (http://www.spl.usace.army.mil/Pradodam/pradodam.htm)

Adrienne

mckygirl99
11-20-2008, 03:04 PM
Is this based on the specifications for the "Old" Prado Dam or the totally wow and snazzy and been working on it forever "New and Improved" Prado Dam?

Adrienne

This based on current info. This is what we were being told from "experts." These are the people who apparently also prepare the city and factor in the DLR into their plans. At our meeting they even discussed the average attendance in the park and other major locations in the city and they factored this into the amount of emergency personnel available on any given day and the numbers were pretty grim. This was when we were told that as teachers, we would the ones to have to help out b/c we are state employees.

I am not so much worried about being hit by a wall of water when I am in the park. I am more worried about the amount of damage it would cause to park in addition to other structural damage from the quake itself. I believe they were talking about a 6-7 magnitude quake and as we all know there is a major fault near that dam.

I am just passing along the info I heard to guys. Thought you might be interested to know since it is our favorite place! :)

Bolivar
11-20-2008, 05:31 PM
Keep in mind that these people are paid to plan for disasters and the worse the potential for disaster, the more planning we all need, so they have a build in incentive to paint the most pessimistic picture possible. I am not saying that they lie in order to prop up their jobs, but given a spectrum of possible scenarios, it is in their best interest to describe the worst possible. And, selecting the most pessimistic assumptions, can lead one to a pretty skewed conclusion.

DisneyFunFamily4
11-20-2008, 05:32 PM
All I know is I want to be at the GCH in the event of a major earthquake it was built on rollers....

Mrs Mouse
11-20-2008, 07:34 PM
This based on current info. This is what we were being told from "experts." These are the people who apparently also prepare the city and factor in the DLR into their plans.

For some reason, and I don't know why, I keep flashing to Brad Pitt in Ocean's 13 when he's disguised as the hippie seismologist (http://movies.about.com/od/oceansthirteen/ig/Ocean-s-Thirteen-Photos/oceans13pic24.htm) warning Al Pacino's character about the necessity of evacuation plans. "No sir, let me tell you what you don't want..."

What can I say? My mind does weird things sometimes. :rolleyes: