[J P Stein]

I lived in a hillside house that my dad built for about 10 years.
The front of the house was built on recent fill where as the rear half (2/3 ?) was on the original hill top. Can you say slump? The whole front of the lot, including the retaining wall at the base of the hill, was on the march. The foundation (one large crack in a 4 foot tall part) of the house was not immune. I shudder to think what it looks like now (50 years later)......probably similar to your pictures. The ground looks to be slumping and is not likely to stop. ......the "why" is not really important.

The house I live in now is also on a hill side but not not nearly as steep. The builder carved down to solid ground to build a tri-level. We've been here for nearly 40 years and the foundation is still in one piece.