Andy wrote:
My mother's house is 55 yrs. old.

Her driveway has sunken and I am wondering why.

Maybe it is the water supply from the city ?

As in the void from the water supply ?


Now you know what to get her for Christmas. A jack hammer.
So you get a concrete saw and cut nice smooth lines and tear out the
sunken part, dig a little and find out why it settled, fix it, back fill
it properly, form up, and call Mr. Redix Mix.
A nice Sunday afternoon project.