Slide it, or backdrop it: a foul problem to have .....

[ToughButterCup]

I wish I could sort this problem out with one of Billy Connelly's  Jobbie Wheechas: but "ah caanee, hen."

(tr. from the Scottish : I couldn't possibly do that, dwaahling).

 

Look at this.

 

The flow is from the I/C at the back towards the viewer standing next to the  'top-of-the-drop' -  the white topped shuttering.

 

From there it goes ....

off down to the digester ( green thing at the back) - about 8 meters.

 

The drop's not far off 2 meters, from top invert to bottom invert. The banking in which it sits is no more than 40 degrees

 

Backdrop? 

 

OR 

45 degree Helter Skelter as @epsilonGreedy would put it?

[PeterW]

Hmmm where did you find that picture as a backdrop really should use a rest bend !!

 

2m drop over 8m is a 1:25 slope - that isn't too unreasonable although i can't see the entry point into the treatment plant..? does it change direction to get into the tank itself as that will be your "slowest" point in the flow. 

 

 

[ToughButterCup]

Where did I find it? Wavin brochure!

 

Thing is , the main drop ( 2meters vertical) occurs over about 2 meters horizontally ... maybe a bit more. Which is 1:1 innit? 

 

Backdrop with a rest bend?

[Jeremy Harris]

I thought that backdrops were now a thing of the past, and that they were no longer needed in Part H, as some further research had shown that there is no maximum slope for a foul drain? 

 

I'd be inclined to just run a run of pipe down to the treatment plant, unless there's a good reason not too, like having to dig a really deep trench in places.  Got to be less hassle having just a straight pipe run, I'd have thought.  Our's drops pretty steeply, about 1.5m over a distance of around 15m, and just goes straight in the side of the treatment plant.

[ProDave]

The "issue" appears to be you have already dug the step for a backdrop. So the problem now is filling it back in again and compacting it all if you go for the steep slope method.

 

The time to have asked the question would have been before digging that deep (sorry)

[Mr Punter]

I would just use a couple of 30 or 45 degrees and pipe between.

[Mr Punter]

All the drainage looks really deep.  Was the system designed?  Shallow can be a lot easier to install and maintain.

[Oz07]

Stepped invert backdrop for inspiration. Not perfect but has done the job for 18 months without issue. No rest bend just couple of 45s. Was a storm on same level hence stepped invert 

[Mr Punter]

Nice neat benching.

[ToughButterCup]

3 hours ago, Mr Punter said:

All the drainage looks really deep.  Was the system designed? ...

 

Bang on, well observed. No.

 

It is what it is.  A friggin nightmare.  But Hell, I'm learning fast.

After four years I've learned to take a joke.

[Temp]

In the unlikely event you get a blockage on the slope best rod it from the top :-)

[ToughButterCup]

16 hours ago, ProDave said:

The "issue" appears to be you have already dug the step for a backdrop. So the problem now is filling it back in again and compacting it all if you go for the steep slope method.[...]

 

Exactly. 

Know-Nowt strikes again: or at least I now know, that I know just enough to realise that I'm a danger to shipping on the site. 

Time for a chat with the BCO.

[Russell griffiths]

I’m a bit confused mr Bosch 

i can see the top of your treatment plant in the picture, and I think I can see the tops of those timbers

now I don’t know which treatment plant you have but a lot have an invert of about 600mm, so how come your pipe looks so deep. 

Wouldnt it be about 600 down by the time you get close to the plant. 

 

 

If i have completly the wrong end of the stick

is it possible to dig a new trench to the trench to the side of that one to save having to compact that old one, just fill it in and dig a new one at the right level. 

[Mr Punter]

11 minutes ago, Russell griffiths said:

is it possible to dig a new trench to the trench to the side of that one to save having to compact that old one, just fill it in and dig a new one at the right level. 

 

I think he has sold his digger.  Let's not give him more work.

 

The trench will need filling in any case and there is a mile of fall on the garden and sh!t does not flow uphill.  It can probably be backfilled with the as dug and compacted to the correct level without any great harm.  Maybe use a trench compactor if there is a lot of material.

[ToughButterCup]

1 hour ago, Russell griffiths said:

I’m a bit confused mr Bosch 

[...]

If i have completly the wrong end of the stick

[...]

 

Overthinking on my behalf is allowed . ?

1 hour ago, Mr Punter said:

[...]

Let's not give him more work.

[...]

 

Fanx. 

"Trench compactor"  = wife? Wassa chances of that then?

[Oz07]

My normal wacker would fit in that trench. 

[Russell griffiths]

Just concerned with the trench bottom settling and ending up with a dip in the pipe, I know it’s flowing down hill so it’s never going to sit there. 

[ToughButterCup]

3 hours ago, Russell griffiths said:

Just concerned with the trench bottom settling....

 

One of the benefits of deep glacial till, covered by a meter of MOT1. Sits there like a brick outhouse. 

[ToughButterCup]

On 06/05/2020 at 17:11, Russell griffiths said:

Just concerned with the trench bottom settling and ending up with a dip in the pipe, I know it’s flowing down hill so it’s never going to sit there. 

 

Oh dear, the sainted @Russell griffiths is right, too right for comfort. And so's @PeterW.

 I suppose I should be grateful, - really hard to write that word in present company...... 

 

It piddled down here last night. Look at this

 

Look at the ground, just above the pipe on the left hand edge of the photo. The big crack in the backfill (not the best photo). It's just as if the ground sighed with relief at the rain, and sank 10mm or so - bit more maybe.

 

So, a la Russel Griffiths advice, I'm going to wait another fortnight before I doing anything to that pipe trench (backfill with pipe bedding) - to let it settle some more and

a la Peter W's advice, later still, I'll need to bed that 30 degree bend in a concrete boot won't I? 

[Russell griffiths]

You can’t rush perfection lad. 

Carry on looking good.