I ask because I took out the old PVC liner today and I discovered that it no
loner touched the bottom of the pond when empty. It was in decent shape
after six years although perhaps a little brittle.

I was going to let the new liner settle (with water) about 24 hours before
cutting the hole for the bottom drain, but if the old liner is still
settling after six years!

The other bad news is that the weight of the water has turned the clay into
one large brick bowl, even the Mattock has a hard time breaking it up. I was
hoping that all the moisture around the pond would make the clay soft, but
that is not the case.

"Bill Stock" wrote in message
...
I ask because I took out the old PVC liner today and I discovered that it
no loner touched the bottom of the pond when empty. It was in decent shape
after six years although perhaps a little brittle.

I was going to let the new liner settle (with water) about 24 hours before
cutting the hole for the bottom drain, but if the old liner is still
settling after six years!

The other bad news is that the weight of the water has turned the clay
into one large brick bowl, even the Mattock has a hard time breaking it
up. I was hoping that all the moisture around the pond would make the clay
soft, but that is not the case.

I don't think that the bottom was still settling, the vinyl shrank when
allowed to dry. My daughter pumped her swimming pool dry and allowed it to
be dry for a few days to do some major cleaning after not using it one year.
The sides shrunk enough that the bottom was pulled up the sides some. She
had to replace the liner due to shrinkage.

When you install the bottom drain, concrete around it to prevent it from
twisting or shifting. Pull the liner into roughly the final position,
making sure that there is liner enough to go around. The hole for the
bottom drain can be cut into the liner and the bolts attached as the first
thing done. Start filling with water and pull the wrinkles out, working
outward from the bottom drain. Wait until the water level is up to the
skimmer opening before cutting for the skimmer. The weight of the water
will be pulling down on the liner from the top as it conforms to the exact
shape of the pond and could pull away from the skimmer.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html
Zone 7A/B Virginia

On Mon, 3 Sep 2007 07:21:45 CST, "RichToyBox"
wrote:

When you install the bottom drain, concrete around it to prevent it from
twisting or shifting. Pull the liner into roughly the final position,
making sure that there is liner enough to go around. The hole for the
bottom drain can be cut into the liner and the bolts attached as the first
thing done. Start filling with water and pull the wrinkles out, working
outward from the bottom drain. Wait until the water level is up to the
skimmer opening before cutting for the skimmer. The weight of the water
will be pulling down on the liner from the top as it conforms to the exact
shape of the pond and could pull away from the skimmer.

IIRC, we installed the under-the-liner part of the bottom drain (with
concrete as RTB mentioned), and the little stub of the skimmer poking up.
Laid the liner and filled. This made the liner tight over those areas, so
the next day when we emptied, we knew where we'd be cutting... granted,
because of the skimmer pipe in the bottom, we had to lift the liner, glue
the small extension piece, wait to dry, and then wiggle the Greg Bickle
pipe boot over it. Can't remember if guys marked the liner... but I think
the markings, the bottom drain hole (which we had plastic wrap over to keep
dirt out) and screw holes remained indented in the liner. Kind of like
pillow marks on your face when you get up. ;-) ~ jan
------------
Zone 7a, SE Washington State
Ponds: www.jjspond.us

"Bill Stock" wrote in message
...
The other bad news is that the weight of the water has turned the clay
into one large brick bowl, even the Mattock has a hard time breaking it
up. I was hoping that all the moisture around the pond would make the clay
soft, but that is not the case.
==============================
Clay soil is the pits. Rock hard when dry and like mustard when wet. After
about 8 years we had to drain both ponds and make cement berms. The clay
sank over the years, some washed away, the sides, sloped, still started to
collapse.... the rocks were falling in, runoff was entering one pond. I
would make the cement berm before adding the liner rather than have to go
back years later when the problems start.
--

RM....
My Pond & Aquarium Pages:
http://tinyurl.com/9do58
Zone 6. Middle TN USA
~~~~ }((((* ~~~ }{{{{(ö

Reel McKoi wrote:

==============================
Clay soil is the pits. Rock hard when dry and like mustard when wet.
After about 8 years we had to drain both ponds and make cement berms.
The clay sank over the years, some washed away, the sides, sloped, still
started to collapse.... the rocks were falling in, runoff was entering
one pond. I would make the cement berm before adding the liner rather
than have to go back years later when the problems start.

Interesting.....my soil is also clay and although some of the sides of
the construction have held up well with the variations in weather some
bits will need more stability (this is the bit I've got left to do). We
were going to go with building/using wooden (untreated) planters which
will then be filled with bog irises (the liner will go up the outside)
and eventually use the same to create a veggie filter that will sit on
the deck.

Gill

"RichToyBox" wrote in message
. ..
"Bill Stock" wrote in message
...
I ask because I took out the old PVC liner today and I discovered that it
no loner touched the bottom of the pond when empty. It was in decent shape
after six years although perhaps a little brittle.

I was going to let the new liner settle (with water) about 24 hours
before cutting the hole for the bottom drain, but if the old liner is
still settling after six years!

The other bad news is that the weight of the water has turned the clay
into one large brick bowl, even the Mattock has a hard time breaking it
up. I was hoping that all the moisture around the pond would make the
clay soft, but that is not the case.

I don't think that the bottom was still settling, the vinyl shrank when
allowed to dry. My daughter pumped her swimming pool dry and allowed it
to be dry for a few days to do some major cleaning after not using it one
year. The sides shrunk enough that the bottom was pulled up the sides
some. She had to replace the liner due to shrinkage.

When you install the bottom drain, concrete around it to prevent it from
twisting or shifting. Pull the liner into roughly the final position,
making sure that there is liner enough to go around. The hole for the
bottom drain can be cut into the liner and the bolts attached as the first
thing done. Start filling with water and pull the wrinkles out, working
outward from the bottom drain. Wait until the water level is up to the
skimmer opening before cutting for the skimmer. The weight of the water
will be pulling down on the liner from the top as it conforms to the exact
shape of the pond and could pull away from the skimmer.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html
Zone 7A/B Virginia

Thanks, the plan is to put a patio slab under the drain and then cement the
drain on top of it. The skimmer will attach with a bulkhead opposite the
waterfall.

How much below the pond bottom should the drain opening sit? 3/4"?

I more or less have the shape dug now (taking a break from the chiseling),
but I really won't know what I want until I see it. I still have to get the
depth I want (probably another 2') in order to break into the drain line. I
will soak the clay with water overnight so I can scoop out the bottom.

Then comes the hard part, digging the remaining plumbing channels.

Thanks, the plan is to put a patio slab under the drain and then cement
the
drain on top of it. The skimmer will attach with a bulkhead opposite the
waterfall.

How much below the pond bottom should the drain opening sit? 3/4"?

The bottom of the pond should be graded to be smooth with the top of the
bottom drain with the clamping ring on. It does not need to go any deeper.
If it is set too low, there won't be room between the cover and liner for
water and debris. It is always good to bowl the bottom to make it easier
for the debris at the wall to find its way to the bottom drain easier, but
if it is bowled much, it makes it difficult to walk to the edge to get out
if you get in for any maintenance.

--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html
Zone 7A/B Virginia