Underground drainage help

[dangti6]

Grateful if I could rack some brains.

 

I am going to dig a soakaway fed by 2 rainwater down pipes.

 

I’m looking to branch off using a 45degree fitting as shown below.

 

 

 

Each down pipe will enter bottle gullies. Is a 15 degree bend a common angle to connect to each gully to give me the fall?
 

My entry points are fixed. Is there another way to achieve what I need that I have overlooked, perhaps running 2 straight pipes in to the soakaway to avoid the branch?

 

Also I ordered some geotextile fabric and explained it was for wrapping soakaway crates and they sent me some Groundtex - essentially weed membrane like this.

 

Not sure I’m comfortable using that so may buy another roll of proper non woven stuff unless I am worrying too much and should just use it.

 

 

 

 

 

 

[PeterW]

You need about 3° fall not 15° unless you like digging deep holes ..!!

 

Geotex provided is fine - it’s just to stop soil getting into the crates. 

[dangti6]

Don’t want to dig anymore than I have to! ?

Perhaps adjustable bends are the way forward! 

 

 

 

[Mr Punter]

You will be able to get enough fall from the bottle gullies without any more fittings.