It is very possible that water is flowing under the liner, lifting the liner
for a period of time and then percolating out, allowing the liner to settle
back down, making the water level go down. There have been a number of
people that have had problems with the liner floating up out of the hole,
causing a large bubble under the liner. Your soil sounds like it is more
permeable than theirs. Try raising the ground level around the high side of
the pond to divert the water away from the pond. That might keep the water
level from rising and then falling back down.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html


"Michael Shaffer" wrote in message
...
I don't know

Mike Patterson wrote:

I have a 1200 US Gallon pond with an overflow spillway at one end.

If I fill it up, it seems to hold it's level fine, but after a really
heavy rain (we got about 3 inches in 4 hours a couple days ago), the
water level after the rain was about 3-4 inches LOW.

I filled it back up and it has held the correct level for 2 days since
the rains.

The only thing I can imagine to explain this is some sort of siphoning
action that only gets started when the pond is heavily flooded but
that breaks when the level gets low enough.

Any other suggestions or ideas from the crew?

TIA
Mike

Mike Patterson
Please remove the spamtrap to email me.

The question isn't "are there weapons of mass destruction?",
the question is "who has them now?"

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