What pops to mind is that a permanent install would hang down and
possible get hit by something and break the tank outlet or the tank
itself.  How about something that would fit the inside of that
drain?  Like a rubber stopper you would jam up in there, which would
have a hose coming out of it and a shutoff on the end of that.  If
that proves to not be secure enough, a bail or two that swings down
to hold the stopper up into the outlet would be good.  You would have
to do a quicko-change-o at the campsite but you could catch what you
lost in your bucket to re-use it for washing up or whatever.

If you need to fill a bucket in a hurry for a fire, just taking the
cap off and putting it back on when the bucket is almost full is not
as hard as it sounds.  Not for me anyway.  Try it.  Another idea for
the shower would be to have a hose that snakes down the fill port
into the tank.

Now that I think about it... I hear the drain cap is the same as the
washer bottle.  Probably the same as the washer bottle on millions of
80's VWs.  you could get a couple to experiment with gluing a fitting
or valve to one of those

Edward  (full of ideas tonight.)

At 08:41 PM 6/19/2011, you wrote:
>Say that a fellow was looking to replace the standard drinking water
>tank's drain plug with a fitting that provided a, say, male garden hose
>bib fitting along with a shutoff valve ... does such a thing exist?
>
>I ask because I was camping in the Oregon high desert this weekend and
>was thinking (A) about a quick way to fill a bucket with water from the
>Westy's drinking water tank in case of a campsite fire without dumping
>the whole tank of water (I live in an arid environment so I worry about
>every drop of spilled water); and (2) that the drain outlet on the water
>tank could be a useful place to tap into a reservoir for a campsite
>shower system.
>
>So to replace the Westy water tank's drain plug with a fitting that has
>a valve and some kind of standard hose fitting would be swell.
>
>-- RJS