bob wrote:
Is there a way to measure the water table level under my yard without
digging a deep hole? Perhaps some sort of radar or sonic equipment?

I'm trying to figure out if my damp crawlspace is caused by high
water table or some other reasons.

Are there any professionals who can do this? I don't know who to
call. I don't want to call just any crawlspace waterproofing
contractors because they are usually interested in selling a service
than fully understanding the problem.

Is this crawlspace well ventilated?

If your soil isn't too rocky, you could use this method to make a hole, and put
a "PVC well point" into that hole. Then use a stick or float on a string to find
the water level. It uses water pressure and 2" PVC pipe to drill the hole. Then
you slip the well point into the larger PVC, and pull out the larger PVC,
leaving the well point in the ground.
http://www.drillyourownwell.com/background.htm

https://www.google.com/search?q=brad...x=&startPage=1

Lowes list a number of well points on their site, or you can order them at other
hardware stores like ACE.

Another guide.
http://prepperchicks0.homestead.com/...stallation.pdf