In the commercial construction world,  "diaphragm" or "slurry" walls are used for perimeter basement walls of projects where there is a high water table and a need to build below it (such as parking and service areas of office buildings very near to a body of water) .  These are vertical panels that are excavated and poured with special equipment under a head of bentonite slurry.  These panels act as vertical beams against hydrostatic and soil pressure forces and will typically require internal props or temporary ground anchors if the excavation is very deep until the floor slabs are placed to brace the foundation walls.  These walls form the sides of the "bath tub" below the water table.



The thickness of the diaphragm wall panels is dictated by load, span and ground movement criteria, but would typically be 2 to 4 feet thick (this is not low priced construction).  Unless there are sulfates in the gound water or other problems, it is typical to use a normal 4000-5000 psi mix without waterproofing admixtures.  Because there are frequent vertical joints, these are obviously the weak links in the bathtub walls and there are a variety of joint methods used to make "waterproof" joints.

The definition of "waterproof" is usually considered to be no free flowing water, but there will almost always be dampness.  Since an exposed diaphragm wall surface is not terribly attractive and is usually damp, a ventilated cavity with drains is usually provided and there are also (expensive) ways of waterproofing the inside face.  We assume it will (eventually) leak and are prepared to deal with it.  The hydrostatic pressure 50' below the water table is considerable.

While concrete may be waterproof in the broad sense, I personally would not depend on it to keep water or moisture out of my basement.  I would much rather keep the water away from it in the first place.  Nothing can take the place of good site grading and drainage.  If you have wet subgrade soil conditions, however, you do need to account for it in the design.

xexpat

Wow... I don't know about all that...
But I do know about what Ian is saying- and saying it quite well, I might add...

And to the originator of this post, Eric - you may understand better after checking out the info below.
"Rising Damp" or A.K.A. "the wicking effect" is a real condition to be concerned about when building in certain locations.

The following link is to a pdf. that gives an excellent visual description:
LINK
*Please note that I am Not trying to sell or promote that product line as any sollution*
Rather- It is simply a very good report that shows how this condition can exist.
Hope that helps to shed a little bit of light...
Take care ALL,
C.Kerr