"john smith" wrote in message
. ..
Kyle Boatright wrote:
Silt doesn't make good structural fill because the particle size is too
small. Small particles don't well, and result in soil that moves once you
think you have it put in place.

So what is the problem?
You build it 50 feet higher.

Moving, placing, and compacting dirt is very expensive. Supply is a bit of a
problem too. Where are you gonna get enough fill to fill several square
miles to any useful depth?

Beyond that, installing footings and foundations in unstable soil ain't the
best idea.

KB