Posted on 01/25/2010 10:22:53 AM PST by NormsRevenge
SAN ANTONIO – Dozens of homes were evacuated in San Antonio after the ground below began shifting, creating crevices up to 15 feet deep and nearly splitting a nearby retaining wall in half, officials said.
About 80 homes were first evacuated on Sunday after residents in a northwest side subdivision reported that the ground was caving behind several houses. No one was injured.
The large crack in the retaining wall sent soil tumbling out below. Fences were tossed askew and crumpled like accordions, and aerial photos showed land had given way near the foundations of several homes.
Engineers at the scene Monday were trying to determine why the ground was shifting and how much damage it could cause.
(Excerpt) Read more at news.yahoo.com ...
http://www.kens5.com/home/Massive-sinkhole-forces-20-families-from-their-NW-side-homes-82559657.html
***The homes were in a new subdivision...***
I wonder if those homes were built over an existing excavation of mines.
Probably build atop limestone, and a sinkhole is forming.
I guess we have a few too many movers & shakers here...
No, Haiti was a natural geological process and this was probably as well, I know there is a lot of limestone in the Austin area and that probably extends down to San Antonio as well. Limestone forms caves, and when a cave gets too close to the surface, you get sinkholes.
I’m losing confidence that votes like this aren’t contingent on bundles of cash exchanging hands. More likely i’m just too naive to have ever believed they did without it. Whores all.
We need to hold down the D.C. power button for 10 seconds and listen for the “tong”.
Looks like house sites are on alluvial fill, too close to the retreating scarp. I doubt that there is a fix for this.
Lots of underground caves/caverns/rivers in that part of Texas. Could just be from an underground cave in.
We’ve had sinkholes opening up in the Tampa Bay area recently. Quite a few along highways. Those photos make it look more like the retaining wall is giving way, and the buildings are sliding...not what we, in Florida, typically see when a sinkhole opens up (probably because everything’s so flat here, it just looks like a hole in the ground.)
Bingo. Seems they ought to do a geophysical survey before building in areas of limestone.
He is probably an Engineering Geologist.
or a previous land fill or dump, something that deteriorates ...
How scary for them.
The aerial shot (Birdseye View) on Bing.com/maps, shows that you are correct. The shot looking east shows that not only were the houses built on fill, there was cut right about where the failure occurred. The cut appears to have been to allow the construction equipment access to both the top and bottom of the slope. Quite likely they didn't properly fill and compact it. (Some of the shots from other directions show the houses already built, some of them anyway, but the one I'm thinking of shows the site prep in progress, but no houses right there.
Sacred Indian Burial Ground (and not covered by homeowner’s insurance).
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