MC wrote:
On Feb 18, 1:58 pm, Eric in North TX wrote:
On Feb 18, 12:48 pm, MC wrote:

Can anyone think of anything else bad that might cause the water level
to be low that could be missed on an internal inspection of the tank?
Thanks
Yes; a leak between the house and the tank causing the liquid never to
reach the tank.

I guess. But that would have to be a huge leak to prevent the
accumulation of 1500 gallons of water in the tank over a 2-3 year
period. Plus we flushed a toilet and saw all of the water come from
the pipe into the tank.

How do you know it was "all"??? That would take a volumetric
measurement on both sides which undoubtedly wasn't done. Not that I
would suspect too much, just a point that you can't draw excessive
conclusions from simple observations.

As for the overall situation --

First is the question of the tank design, etc., ... was/is there a
siphon that could account for the permanent level?

Were any cracks/potential leaks that were fixed/repaired below the level
that could account for it? I've not read the whole thread by any
stretch but did see indication that what appeared to be most problem(s)
may have been at the level of the outlet which wouldn't have explained
the low level anyway. If misread that or that's wrong, ignore...

Is the house presently occupied? If so, it shouldn't take any time at
all for the level to reach the outlet level (in overall terms); normal
household activities will put quite a level of water down the drain in a
day or so unless there's some very stringent usage restrictions being
observed by the occupants. If so, observing the level should lead to
fairly quick conclusion as to whether there's an escape path somewhere
or not.

If it's unoccupied, and the tank is still open, I'd just fill it up w/
hose and other running water until it is at the outlet then watch to see
if it goes down from there for a period.

As for leak in exit line from house, how deep is that line and what's it
made of? Unless it's quite deep it shouldn't take much investigation to
discover (particularly since you say it's short) whether there's
waterlogged soil in the area -- even a probe rod should tell you the
answer of whether there's saturated soil or not close by.

That last holds for areas around the tank as well--if you can probe
deeply somewhere indicating soft ground, that would be telling of
leaking--of course if it's in area of repair above, that could/would
likely be old, not new.

All in all, if the house has been occupied and used in normal fashion w/
reasonable number of occupants and there are no visible indications I'd
tend to think it's not a major problem.

You might want to write in a clause in any contract that owing to the
circumstances any subsequent problems uncovered or becoming apparent
within oh, say one year, are to be covered 50:50 or something similar by
you and seller.

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