Ducted Water Main

[Onoff]

I replaced my incoming water main a few years back. Dug a new trench bypassing the old iron main and laid a proper, corrugated blue duct with new MDPE in.

https://flic.kr/p/MLvAym

https://flic.kr/p/LPxkyC

https://flic.kr/p/LRVeqD

https://flic.kr/p/MJ2eBG

The theory being if that single run of pipe ever leaks I can pull it through the duct and replace.

Now though I want to tee off of that buried pipe then T off that new run too. Means digging down to where the T will go, cutting the duct and fitting a T.

Answering my own question I think but should I be thinking of accessible pits to where to where the Ts are? Otherwise I'll never be able to pull anything through the ducts again. Could be quite deep like 750mm as this is ground likely to be disturbed later.

 

[Cobbler]

Fit a small inspection cover over the tee

 

[Kram]

How far is new run from the ends? Do it as a new run from either end?

 

[gaz1]

use drain manholes and covers it allows access and renews when needed

 

[Onoff]

How far is new run from the ends? Do it as a new run from either end?

I think the meter by the road is 35m from where it enters the house.

I want to T off I reckon at the 30m point. That's where the vegetation is beyond the scaffold. Then along by the side of the path where the dashed red line is. The red line being the new electric route.

Then up through the hedge (that I've just removed) and right to the garage behind the bamboo.

The horizontal red line above is where I'm currently trenching by hand, the 4.2m bit:

 

[Turbo]

If you were hoping to pull something through afterwards you used the wrong duct.
Corrugated duct is evil stuff as the end of the pipe or cable will catch on the ribs making pulling things through very difficult.
The smooth bt type duct is the stuff to use in as big a bore as possible.

As regards a manhole at the joins, make is as big as you can, working 750mm down a small manhole is very difficult.

 

[8ob]

I can understand the benefits of ducting a water main under a building, can’t see the sense in it outside. In the highly unlikely event of a new mdpe main outside leaking it soon shows where it is.

Bob

 

[Onoff]

If you were hoping to pull something through afterwards you used the wrong duct.
Corrugated duct is evil stuff as the end of the pipe or cable will catch on the ribs making pulling things through very difficult.
The smooth bt type duct is the stuff to use in as big a bore as possible.

As regards a manhole at the joins, make is as big as you can, working 750mm down a small manhole is very difficult.

I've not got enough smooth bore duct left. This lot I got before was a tenner off of eBay. Collecting was fun. Got it from Esher and drove back to Sevenoaks with it strapped to the roof rack of my then Golf GTi.

https://flic.kr/p/2oCHPsi

The corrugated duct was cheap off of FB Marketplace, it's going in! I've pulled loads of cables through the same stuff here by using a vacuum cleaner to suck through a string with a bit of plastic bag tied to the end. That and we 3D print "ball" ends and stick them on so they ride the corrugations.

For the leccy duct I'll be pulling the 16mm² SWA and smaller 20mm ducts through it, laid straight, before I fit lay it in the trench.

 

[Turbo]

I can understand the benefits of ducting a water main under a building, can’t see the sense in it outside. In the highly unlikely event of a new mdpe main outside leaking it soon shows where it is.

Bob

If it is in a duct the leak will not show where it actually is, it will show wherever the duct ends.
Another reason not to use it!

 

[Onoff]

If it is in a duct the leak will not show where it actually is, it will show wherever the duct ends.
Another reason not to use it!

The ground here is literally full of flints. Poxy sharp things.

 

[brightspark]

The ground here is literally full of flints. Poxy sharp things.

i put my water main pipe in a 12 foot long scaffold pipe from the road edge to in the house was easy for the waterboard to conect to and pipe just shoved through no chance of it getting damaged

 

[Gareth J]

In otherwise open ground, I wouldn't bother. Dig up, modify, relay, whatever, re-bury.

Water pipe is relatively inexpensive, very robust and a nightmare to work on in any kind of manhole anyway. It needs a surprising amount of "spare" to refit joints. Unless you need a tap there, then a manhole makes obvious sense.

A better solution would be to T into somewhere that is accessible. So you can isolate individual things for fault finding, frost protection, maintenance or whatever. But it's not always practical to do and always very tempting to just T into whatever is closest. Which is how my network has ended up like such a birds nest.