DIYbanter - waterproofing a shower with a twist

Hello again a.h.r.,

I'd like to thank the usual suspects in this forum who have answered
many of my questions lately, and answered them well.

Almost always, I find the need to mention that I'm in albuquerque, where
the relative humidity is 20% after the evaporative cooling. The dryness
is almost mind-boggling for this product of Chicago, and there are
features in this town that not many others have. I bet you don't know
the one I mean yet, so I'll try to write the story well.

Leaks disappear in this town. There's no clay anywhere. My lawyer
buddy left his hose on for 2 days and had a simultaneous leak in the
city water going out to him. It all ends up in the same place: the rio
grande.

The drain underneath the slab on grade is now exposed: 2" PVC. Around
it is the adobe dirt that is everywhere else. It is porous and dense.
I don't think I need weep holes in my drain if this shower cries to the
rio grande. Furthermore, no weep holes allowed me to buy my client's
drain at lowe's, where she prefers that I buy things, as she has a
charge account that gets a modest discount, and, much more importantly,
allows me to make purchases without having to treat the receipt like the
ark of the covenant.

Anyways, (the heat of the day seems to be taking its toll), so if the
object of the shower is not to be a complete dam but more of a funneler,
then what do I for water-proofing, with an eye to the fact that I'm
spending somebody else's money here, and you could either imagine that
person as a sister or the person who feeds me, and I like to have money
leftover so there's grub for all of us. I would think that a shower
might make at most 2 cm^3 of water that soaks into it, and the rest goes
down the drain, unless you f*ed up the plumbing or tiling in a big way.

A liter of water disappears near this drain in a less than five minutes.
I'm a little concerned that I might check how quickly sand and water
disappear in this region, but that's a separate post.

I'm convinced that I can use building paper to achieve what I could do
with the shower pan liner that I bought today. So many times in my
construction career I have seen people but vapor barriers where there
doesn't need to be one, and this has the odd effect of undermining the
vapor barrier. Tja!

As I think about it the matter more, I don't think I need a vapor
barrier at all on the bottom. Matter of fact, I think I should get out
the hammer drill and make several relief holes around the perimeter that
penetrate the slab. Not unlike the city of abq does to mitigate the
exxon valdez that the air force dumped on us. Now that I think about
it, since I'm north and east of the base, it might not be relevant to
our location.

I learned last night that the rio grande is mostly underwater. It goes
down a 1000 feet deep at the middle of the valley.

Am I thinking crazy?
--
Uno