Driveway soakaway question

[taz777]

What type of stone should be used on a soakaway for a driveway?

My driveway installers have excavated a 1m wide by 1m deep hole, 5m from the front of my property. The overall size of the driveway is about 100 square metres. Two separate drain pipes from the Aco channels will send rainwater to the soakaway.

The installers plan to fill the soakaway with half engineering bricks, shingle and then a slab of concrete on top.

Is this filling okay?

 

[WabbitPoo]

Is the hole being dug in clay?

 

[taz777]

Well, kind of. There is a layer of soil and then there's clay.

 

[masona]

A grey area if it's heavy clay then soakaways rarely work

I prefer the plastic milk crate type soakaway which I have fitted in my garden

However my old bricks soakway drained very slowly because of clogged up with clay but have taken over 20 yrs to do this

 

[taz777]

Oh no, i've just been informed that the installer used normal house bricks chopped in half to fill the soakway, topped with shingle.

Is this a bad thing?

 

[WabbitPoo]

If its in clay then it will fill with water, then will back up. If memory serves, canals used to be lined with clay as it is so good at holding water back.

A soakaway will need lots of void spaces, which is why one of those crate things are so good, but its no good if the water cant then percolate away quite easily.

OOI did u need to get PP for your drive, cos sometimes you do these days.

 

[taz777]

No planning permission because of the use of a soakway (i.e. the water isn't running off onto the public footpath or road). Installer recommended it and said it'll be fine! I asked for a drainage solution to comply with all Building Control and Planning regulations. He's giving a written guarantee that it won't clog up for at least a year.

 

[Burnerman]

Prevent mud from entering your soakaway as much as possible, and it will perform as best as it can - depending on the porosity of the surrounding ground.
It will help if your downcomers enter a gully so the solids can collect in there before cleaner water exits.
John

 

[taz777]

Okay, my father will be 'flooding' the Aco-channels with a hosepipe this afternoon to see is the soakway takes a large amount of water. The paving bricks haven't been installed yet so we can get the installers to fix the soakaway if there are any issues.

 

[taz777]

Oops. Double post.

 

[WabbitPoo]

He's giving a written guarantee that it won't clog up for at least a year.

Then what?

 

[hamster123]

Calculating the size of a soakaway required is not that simple.

You need the area of the driveway, the typical rainfall for your postcode and you need to test the porosity of the soil.

If the soakaway wont cope with the run off and it goes on the highway then you should have planning.

But i know of some driveway installers that don't even bother with a channel drain! Not right but s**t happens and they seem to get away with it.

The crates are definitely better than bricks etc - over 90% void space so able to store more water until it drains away - good if your on a heavy soil. They are however more expensive than rubble and take more time to install.