2013 Tornado Season

What makes it difficult to build basements?

 

Tome Cole (R) was on MSNBC talking about the hardness of the ground. Never visited the state so I have no idea.

 

Yes. I'm watching live video feed from an ABC affiliate down there.

 

ABC station reporting debris is landing in Tulsa, 90 miles away.

 

It appears it was Briarwood Elementary. Tough to tell from reports if any were injured. Seeing reports now 7 drowned at Plaza Towers Elementary and more than 30 are missing. Now search and RECOVERY mission.

 

Two elementary schools were hit - Briarwood and Plaza Towers. Everyone at Briarwood was okay. The deaths are at Plaza Towers.

As for the basement question, it's a combination of several things. The first seems to be a building stability issue - there's a very shallow "frost line" for a house's foundation to have to sit below, so there's no need to dig into the ground for a basement. Other issues include high water tables (leading to early cracking and shifting of basements as well as mold, mildew and flooding), flat land (more flooding, as the water wants to run to the lowest point when it rains, and there's nothing lower than your basement) and really hard rock below the topsoil in some areas.

The underground storm shelters aren't waterproof either, but it doesn't matter because you're not living in them for more than the hour you're riding out the storm. And like doctorquant said, your larger public buildings (like schools) can serve as storm shelters along their inside walls to a certain strength of storm. Those are fine for almost every storm cell. It's only the very rare strong F4s and F5s that can take those out.

 

The soil in Oklahoma also expands and contracts pretty dramatically from wet to dry/draught seasons. That can destroy basement walls unless they're extra thick end reinforced, which is expensive.

Storm shelters are smaller and less expensive, so most houses have them instead of basements.

Older and less-expensive houses sometimes don't have them.

And mobile homes live up to their name.

 

CBS: death toll has hit 51.

 

WTF?

 

That was my reaction. Some powerful pix on Twitter (from the Oklahoman) of teachers and kids from Briarwood.

 

Apparently the school did have a basement or something like it - probably a boiler room, and those seven kids were found down there. The issue is the basement filled with water (maybe a water main burst?) and then there was no way for them to get out.