4-zone residential system with timer-controlled valves.

Just noticed water spurting up alongside the "supply side" of the walk
when one particular zone is activated. I've found where the polyethylene
pipe (one of two at that point) passes at right angles under the walk.
but the water was coming up at a point a few feet away in the opposite
direction from the sprinkler heads that this pipe feeds. I dug down at
the opposite side of the walk and found not two pipes, or even one pipe,
but some of that corrugated black plastic pipe -- presumably put there
to protect the sprinkler pipes against over-enthusiastic digging in what
was previously a garden bed; it's now lawn. I haven't yet dug out from
the walk to see how far the corrugated pipe extends, but I'm guessing
that it's at least the width of the former garden bed.

Even with a trench (dug in the search for the crossing point) alongside
the walk, most of the water is flowing from under the walk some distance
from where the pipes pass under the walk, rather than right alongside
the pipes, but that might simply be the line of least resistance because
of permeability issues.

Any bright ideas for dealing with this situation effectively?

Perce

On Sat, 05 Oct 2013 16:21:56 -0400, "Percival P. Cassidy"
wrote:

4-zone residential system with timer-controlled valves.

Just noticed water spurting up alongside the "supply side" of the walk
when one particular zone is activated. I've found where the polyethylene
pipe (one of two at that point) passes at right angles under the walk.
but the water was coming up at a point a few feet away in the opposite
direction from the sprinkler heads that this pipe feeds. I dug down at
the opposite side of the walk and found not two pipes, or even one pipe,
but some of that corrugated black plastic pipe -- presumably put there
to protect the sprinkler pipes against over-enthusiastic digging in what
was previously a garden bed; it's now lawn. I haven't yet dug out from
the walk to see how far the corrugated pipe extends, but I'm guessing
that it's at least the width of the former garden bed.

Even with a trench (dug in the search for the crossing point) alongside
the walk, most of the water is flowing from under the walk some distance
from where the pipes pass under the walk, rather than right alongside
the pipes, but that might simply be the line of least resistance because
of permeability issues.

Any bright ideas for dealing with this situation effectively?

Perce

If you mean polyethylene irrigation tubing - 1/2", the pipe can break
in many places. I'm not sure how it would break or leak in a
protective "corrugated black plastic pipe".

Sounds like you need some more digging.

On 10/05/13 04:46 pm, Oren wrote:
On Sat, 05 Oct 2013 16:21:56 -0400, "Percival P. Cassidy"
wrote:

4-zone residential system with timer-controlled valves.

Just noticed water spurting up alongside the "supply side" of the walk
when one particular zone is activated. I've found where the polyethylene
pipe (one of two at that point) passes at right angles under the walk.
but the water was coming up at a point a few feet away in the opposite
direction from the sprinkler heads that this pipe feeds. I dug down at
the opposite side of the walk and found not two pipes, or even one pipe,
but some of that corrugated black plastic pipe -- presumably put there
to protect the sprinkler pipes against over-enthusiastic digging in what
was previously a garden bed; it's now lawn. I haven't yet dug out from
the walk to see how far the corrugated pipe extends, but I'm guessing
that it's at least the width of the former garden bed.

Even with a trench (dug in the search for the crossing point) alongside
the walk, most of the water is flowing from under the walk some distance
from where the pipes pass under the walk, rather than right alongside
the pipes, but that might simply be the line of least resistance because
of permeability issues.

Any bright ideas for dealing with this situation effectively?

Perce

If you mean polyethylene irrigation tubing - 1/2", the pipe can break
in many places. I'm not sure how it would break or leak in a
protective "corrugated black plastic pipe".

Sounds like you need some more digging.

It's 3/4", not 1/2". But anyway, it's possible that there is a join in
the pipe that has come apart, because somewhere beyond -- or perhaps
under -- that former garden bed the line has to make a 90 degree turn to
reach the zone it feeds.

It's getting dark now, so it'll have to wait.

Perce

On Sat, 05 Oct 2013 18:53:40 -0400, "Percival P. Cassidy"
wrote:

It's 3/4", not 1/2". But anyway, it's possible that there is a join in
the pipe that has come apart, because somewhere beyond -- or perhaps
under -- that former garden bed the line has to make a 90 degree turn to
reach the zone it feeds.

It's getting dark now, so it'll have to wait.

The 90 degree turn may have been too sharp - a weak point with a
sharp radius. Thus, a potential future leak.

Do you have a garden moisture meter to locate the leak? You can probe
with a meter to find the spot of the leak.

On 10/05/13 07:32 pm, Oren wrote:
On Sat, 05 Oct 2013 18:53:40 -0400, "Percival P. Cassidy"
wrote:

It's 3/4", not 1/2". But anyway, it's possible that there is a join in
the pipe that has come apart, because somewhere beyond -- or perhaps
under -- that former garden bed the line has to make a 90 degree turn to
reach the zone it feeds.

It's getting dark now, so it'll have to wait.

The 90 degree turn may have been too sharp - a weak point with a
sharp radius. Thus, a potential future leak.

I should have specified: all the other 90-degree turns I've found so far
use those grey plastic elbows and hose clamps. If the clamp wasn't
stainless steel, it could have rusted and given way, letting the poly
pipe come off.

Do you have a garden moisture meter to locate the leak? You can probe
with a meter to find the spot of the leak.

Don't have one.

On Sat, 05 Oct 2013 20:39:30 -0400, "Percival P. Cassidy"
wrote:

I should have specified: all the other 90-degree turns I've found so far
use those grey plastic elbows and hose clamps. If the clamp wasn't
stainless steel, it could have rusted and given way, letting the poly
pipe come off.

Do you have a garden moisture meter to locate the leak? You can probe
with a meter to find the spot of the leak.

Don't have one.

Again, it sounds like you need to do some digging.

On 10/06/13 03:04 pm, Oren wrote:

I should have specified: all the other 90-degree turns I've found so far
use those grey plastic elbows and hose clamps. If the clamp wasn't
stainless steel, it could have rusted and given way, letting the poly
pipe come off.

Do you have a garden moisture meter to locate the leak? You can probe
with a meter to find the spot of the leak.

Don't have one.

Again, it sounds like you need to do some digging.

I dug out from the walk and found that the corrugated pipe extended only
a few inches from under the walk. I bought a moisture meter and found no
unusually wet areas -- except of course where I could see the water
running out from under the walk. No sign of leaks at either of the
90-degree elbows, so I disconnected the pipe at both elbows, pulled it
out from under the walk and found a large split that would have been
beneath the walk.

Bought new pipe and was relieved that I was able to push it back through
more easily than I had feared.

Perce

On Thu, 10 Oct 2013 18:52:38 -0400, "Percival P. Cassidy"
wrote:

On 10/06/13 03:04 pm, Oren wrote:

I should have specified: all the other 90-degree turns I've found so far
use those grey plastic elbows and hose clamps. If the clamp wasn't
stainless steel, it could have rusted and given way, letting the poly
pipe come off.

Do you have a garden moisture meter to locate the leak? You can probe
with a meter to find the spot of the leak.

Don't have one.

Again, it sounds like you need to do some digging.

I dug out from the walk and found that the corrugated pipe extended only
a few inches from under the walk. I bought a moisture meter and found no
unusually wet areas -- except of course where I could see the water
running out from under the walk. No sign of leaks at either of the
90-degree elbows, so I disconnected the pipe at both elbows, pulled it
out from under the walk and found a large split that would have been
beneath the walk.

Bought new pipe and was relieved that I was able to push it back through
more easily than I had feared.

Perce

Outstanding.

My driveway & entry sidewalk has 3/4" PVC pipe under it , so 1/2" poly
tubing can be pulled out and replaced easily. Same idea for landscape
light wiring.