"Sue da Nimm" . wrote in message ...
Thanks. Wont that act as an overflow. I guess thats fine if you leave
run for the water to run away but if you connect all the conduit back
to the socket then you risk water running back to it during heavy
rain.

Just a few further thoughts.
We've always been told to install overflows beneath the edging slabs or
stones. This is to kep the level constant and keep the water from coming up
over the edging when the pond fills with rain.
This is not for aesthetic reasons, but because of the power of melting ice.
The pond sides should always slope outwards so that any ice formed cannot
exert sideways pressure when it melts. (Ice EXPANDS when it melts, which is
why it can burst pipes)
If the water level rises to the capping stones then melting ice is trapped
and can loosen the mortar and make your pond potentially unsafe.
We have five ponds, all but two fitted with overflows. (The other two have
waterfalls and can't over-fill)
Actually Sue ice expands as it freezes which is why it floats on water
(it's less dense)The drastic consequences e.g. burst pipes are only
seen when it melts again. However your advice about overflows and
sloping sides is very sound.
The depth of two feet will also prevent any hibernating wild life from
freezing and keep the pond cooler in the summer.
Tony Bull
www.caterpillarfountain.co.uk

On 11/29/04 9:03 AM, in article , "BAC"
wrote:


"Sue da Nimm" . wrote in message
...

"Janet Baraclough.." wrote in
message
...
The message
from "Sue da Nimm" . contains these words:

The pond sides should always slope outwards so that any ice formed
cannot
exert sideways pressure when it melts. (Ice EXPANDS when it melts,
which
is
why it can burst pipes)


Ice expands as it freezes and shrinks as it melts. The expansion of
the frozen ice is what bursts pipes or vessels, not the melting of it.

Janet.

Sorry all - choking on humble pie - you are exactly right )
The overall effect is the same, though, ice can damage ponds if there
isn't
a suitable overflow provided.

(I won't expand on the point any more in case I contract poster's
cramp....)



If I remember my elementary physics correctly (and its a big if, because it
is many years since I had to bother with it) the reason water freezing can
burst pipes is that there is a quick formation of feathery dendritic ice,
which forms a network enclosing the water, restricting the volume so that
when the enclosed water expands on freezing it generates sufficient pressure
to fracture the pipe.

The water in your pond is, I assume, open to the atmosphere, so the pressure
will probably be relieved by vertical (upwards) expansion.


Wouldn't there be both vertical and horizontal pressure? The horizontal
pressure could cause damage...
Bill

"Tony Bull" wrote in message
om...

[snip]

Actually Sue ice expands as it freezes which is why it floats on
water
(it's less dense)The drastic consequences e.g. burst pipes are only
seen when it melts again. However your advice about overflows and
sloping sides is very sound.

Hands up everyone who has had a pond crack due to the water freezing.

Franz

"Bill" wrote in message
...
On 11/29/04 9:03 AM, in article ,
"BAC"
wrote:


"Sue da Nimm" . wrote in message
...

"Janet Baraclough.." wrote in
message
...
The message
from "Sue da Nimm" . contains these words:

The pond sides should always slope outwards so that any ice formed
cannot
exert sideways pressure when it melts. (Ice EXPANDS when it melts,
which
is
why it can burst pipes)


Ice expands as it freezes and shrinks as it melts. The expansion of
the frozen ice is what bursts pipes or vessels, not the melting of it.

Janet.

Sorry all - choking on humble pie - you are exactly right )
The overall effect is the same, though, ice can damage ponds if there
isn't
a suitable overflow provided.

(I won't expand on the point any more in case I contract poster's
cramp....)



If I remember my elementary physics correctly (and its a big if, because
it
is many years since I had to bother with it) the reason water freezing
can
burst pipes is that there is a quick formation of feathery dendritic
ice,
which forms a network enclosing the water, restricting the volume so
that
when the enclosed water expands on freezing it generates sufficient
pressure
to fracture the pipe.

The water in your pond is, I assume, open to the atmosphere, so the
pressure
will probably be relieved by vertical (upwards) expansion.


Wouldn't there be both vertical and horizontal pressure? The horizontal
pressure could cause damage...
Bill


Unlikely IMO since the ice sheet, if constrained at the edges, could
probably distort and flex upwards at lower pressures than normally required
to 'break' a pond wall. If you cast your mind back to the days of doorstep
milk deliveries, columns of frozen milk used to push the cap off the bottle
and expand upwards long before the bottle was fractured.

Franz Heymann wrote:
"Tony Bull" wrote in message
om...

[snip]

Actually Sue ice expands as it freezes which is why it floats on
water (it's less dense)The drastic consequences e.g. burst pipes
are
only seen when it melts again. However your advice about overflows
and sloping sides is very sound.

Hands up everyone who has had a pond crack due to the water
freezing.

Seems unlikely for most ponds, certainly. But in the '62-63 effort my
parents' wooden water-butt in East Devon froze solid and split. We
were as much impressed as dismayed: there aren't many places in Aus
where this can happen! I suspect the barrel shape was the villain.

Mike.

"Mike Lyle" wrote in message
...
Franz Heymann wrote:
"Tony Bull" wrote in message
om...

[snip]
Hands up everyone who has had a pond crack due to the water
freezing.

Seems unlikely for most ponds, certainly. But in the '62-63 effort my
parents' wooden water-butt in East Devon froze solid and split. We
were as much impressed as dismayed: there aren't many places in Aus
where this can happen! I suspect the barrel shape was the villain.

Mike.

As always the point being made has been missed!
I made no reference to ponds splitting.
Rather than hitting the nail on the head, Franz has battered my thumb!

What I said was that if the water was allowed to freeze while trapped by the
capping stones it could loosen the mortar and make the pond edge unsafe.
Step on a loose stone and take an early bath....
If the water level rises to the capping stones then melting ice is trapped
and can loosen the mortar and make your pond potentially unsafe.
Others chose to read more into my misguided attempts to be helpful.

With regard to sloping sides, that's what my pond book recommends. It seems
sensible advice since our swimming pool needed a number of tiles replacing
after a good freeze. (Vertical sides and no lip to prevent the ice lifting.)
And my dumb reference to melting ice expanding was based on the old advice
that you should never heat a frozen pipe because it will burst. Thankfully I
have now been disabused of this notion.....and may well end up getting a
good soaking! ;o)

"Sue da Nimm" . wrote in message
...

"Mike Lyle" wrote in message
...
Franz Heymann wrote:
"Tony Bull" wrote in message
om...

[snip]
Hands up everyone who has had a pond crack due to the water
freezing.

Seems unlikely for most ponds, certainly. But in the '62-63 effort my
parents' wooden water-butt in East Devon froze solid and split. We
were as much impressed as dismayed: there aren't many places in Aus
where this can happen! I suspect the barrel shape was the villain.

Mike.

As always the point being made has been missed!
I made no reference to ponds splitting.
Rather than hitting the nail on the head, Franz has battered my thumb!

What I said was that if the water was allowed to freeze while trapped by
the
capping stones it could loosen the mortar and make the pond edge unsafe.

That is a possibility, true.

Step on a loose stone and take an early bath....
If the water level rises to the capping stones then melting ice is
trapped
and can loosen the mortar and make your pond potentially unsafe.
Others chose to read more into my misguided attempts to be helpful.

Sorry, I was imagining people worrying that their ponds would burst like
frozen pipes if they did not have sloping edges.


With regard to sloping sides, that's what my pond book recommends. It
seems
sensible advice since our swimming pool needed a number of tiles replacing
after a good freeze. (Vertical sides and no lip to prevent the ice
lifting.)

It's a good idea to have at least one sloping 'shore' so creatures which
might fall in, like hedgehogs, can get themselves out again.

"Mike Lyle" wrote in message
...
Franz Heymann wrote:
"Tony Bull" wrote in message
om...

[snip]

Actually Sue ice expands as it freezes which is why it floats on
water (it's less dense)The drastic consequences e.g. burst pipes
are
only seen when it melts again. However your advice about
overflows
and sloping sides is very sound.

Hands up everyone who has had a pond crack due to the water
freezing.

Seems unlikely for most ponds, certainly. But in the '62-63 effort
my
parents' wooden water-butt in East Devon froze solid and split. We
were as much impressed as dismayed: there aren't many places in Aus
where this can happen! I suspect the barrel shape was the villain.

Yes. But you would, I think, agree that both the thermal and
mechanical properties of a free-standing barrel and a pond differ
dramatically from one another.
{:-))

Franz

"Sue da Nimm" . wrote in message
...

"Mike Lyle" wrote in message
...
Franz Heymann wrote:
"Tony Bull" wrote in message
om...

[snip]
Hands up everyone who has had a pond crack due to the water
freezing.

Seems unlikely for most ponds, certainly. But in the '62-63 effort
my
parents' wooden water-butt in East Devon froze solid and split. We
were as much impressed as dismayed: there aren't many places in
Aus
where this can happen! I suspect the barrel shape was the villain.

Mike.

As always the point being made has been missed!
I made no reference to ponds splitting.
Rather than hitting the nail on the head, Franz has battered my
thumb!

What I said was that if the water was allowed to freeze while
trapped by the
capping stones it could loosen the mortar and make the pond edge
unsafe.

I have sincere doubts about that.

Step on a loose stone and take an early bath....
If the water level rises to the capping stones then melting ice is
trapped
and can loosen the mortar and make your pond potentially unsafe.
Others chose to read more into my misguided attempts to be helpful.

With regard to sloping sides, that's what my pond book recommends.

Does it give well-reasoned arguments in favour of that, or is it
propagating an old wives' tale?

It seems
sensible advice since our swimming pool needed a number of tiles
replacing
after a good freeze.

That sounds like badly laid tiles. I have not heard of any other
occasions in which this happened.

(Vertical sides and no lip to prevent the ice lifting.)
And my dumb reference to melting ice expanding was based on the old
advice
that you should never heat a frozen pipe because it will burst.
Thankfully I
have now been disabused of this notion.....and may well end up
getting a
good soaking! ;o)

Franz

"Franz Heymann" wrote in message
...
[snip]
Hands up everyone who has had a pond crack due to the water
freezing.

As always the point being made has been missed!
I made no reference to ponds splitting.
Rather than hitting the nail on the head, Franz has battered my
thumb!
What I said was that if the water was allowed to freeze while
trapped by the
capping stones it could loosen the mortar and make the pond edge
unsafe.

I have sincere doubts about that.

That is your prerogative. I am sincerely certain that it happens.

With regard to sloping sides, that's what my pond book recommends.

Does it give well-reasoned arguments in favour of that, or is it
propagating an old wives' tale?

As an "old wife" I am pepared to accept simple advice that takes no effort
to adopt, involves no cost and eliminates a potential risk. Were I
sufficiently educated to ignore established procedures then I would
doubtless make use of that education to rationalize my way out of any
responsibility for subsequent mishaps.
Instead I willingly accept advice and lead a simplistic but happy life.....

It seems
sensible advice since our swimming pool needed a number of tiles
replacing
after a good freeze.

That sounds like badly laid tiles. I have not heard of any other
occasions in which this happened.

Since you have never heard of it, Franz, it cannot possibly be true.

I feel I have outlived my usefulness and will therefore unsubscribe from
this group.
The 10 minutes daily saved will give me an extra 5 hours a month - 60 hours
a year - to use more productively.
Best wishes to Kay, Janet & David - I enjoyed your posts.

Franz Heymann wrote:
"Mike Lyle" wrote in message
...
Franz Heymann wrote:
"Tony Bull" wrote in message
om...

[snip]

Actually Sue ice expands as it freezes which is why it floats on
water (it's less dense)The drastic consequences e.g. burst pipes
are only seen when it melts again. However your advice about
overflows and sloping sides is very sound.

Hands up everyone who has had a pond crack due to the water
freezing.

Seems unlikely for most ponds, certainly. But in the '62-63 effort
my
parents' wooden water-butt in East Devon froze solid and split. We
were as much impressed as dismayed: there aren't many places in
Aus
where this can happen! I suspect the barrel shape was the villain.

Yes. But you would, I think, agree that both the thermal and
mechanical properties of a free-standing barrel and a pond differ
dramatically from one another.
{:-))

Almost no comparison. My anecdote was mere anecdotage for its own
sake.

Mike.

"Mike Lyle" wrote in message
...
Franz Heymann wrote:
"Mike Lyle" wrote in message
...
Franz Heymann wrote:
"Tony Bull" wrote in message
om...

[snip]

Actually Sue ice expands as it freezes which is why it floats
on
water (it's less dense)The drastic consequences e.g. burst
pipes
are only seen when it melts again. However your advice about
overflows and sloping sides is very sound.

Hands up everyone who has had a pond crack due to the water
freezing.

Seems unlikely for most ponds, certainly. But in the '62-63
effort
my
parents' wooden water-butt in East Devon froze solid and split.
We
were as much impressed as dismayed: there aren't many places in
Aus
where this can happen! I suspect the barrel shape was the
villain.

Yes. But you would, I think, agree that both the thermal and
mechanical properties of a free-standing barrel and a pond differ
dramatically from one another.
{:-))

Almost no comparison. My anecdote was mere anecdotage for its own
sake.

And very interesting it was, too.

Franz

In article , Janet Baraclough.
.. writes

I hope you weren't offended Sue..the reason I replied was that people
might get floods which could have been avoided.

If you suspect a pipe has frozen, turn off the stopcock and open
nearby taps so that if it secretly defrosts when you're not around, the
flood is minimised. If the frozen spot is obvious and accessible,
gradual gentle warming (a hot waterbottle or hairdrier) round the pipe
may thaw it safely. Otherwise, just wait and see, it might be okay.
Copper plumbing doesn't burst as easily as lead used to.

Fast fierce thawing efforts such as a blowlamp should be avoided..it's
likely to burst a frozen pipe even if the ice hadn't.

At one time I was sharing a huge Victorian town house with a boyfriend -
we were living in the bottom floors, with three empty floors above us ..
and one winter day returned to find the mains had burst about 3 floors
up - the cascade down the staircase was *most* impressive.


--
Kay
"Do not insult the crocodile until you have crossed the river"

I feel I have outlived my usefulness and will therefore unsubscribe from
this group.
The 10 minutes daily saved will give me an extra 5 hours a month - 60 hours
a year - to use more productively.
Best wishes to Kay, Janet & David - I enjoyed your posts.

I found your advice about using plastic conduit under the mortor/slabs
to run the cables most useful. Thanks for your advice.

Nick