How can I improve this drainage?

[Gary111]

Hi, I've got a cast iron downpipe leading to a piece of gutter, obviously doesn't work well.
What's the best way of getting the water into the drain please?

 

[Madrab]

Without re-doing that piece of concrete then you need to see if that bottom shoe can be loosened and turned through 90deg, either than or cut the shoe off and then use a coupler to re-attach or attach another piece of downpipe and turn it through 90deg right and run it horizontally along to the gully wirth another shoe to direct the flow into the grate.

 

[Gary111]

Thanks mate

 

[Gary111]

The property drains go into a septic tank, is the rainwater still ok to go into the drain?

 

[Madrab]

Ideally not, if there is a sceptic tank then best practice would have the surface water directed towards a purpose made soakaway. This avoids the tank becoming overwhealmed and reduces contaminated water discharge.

 

[Hugh Jaleak]

Rainwater should never go into a Septic Tank. High flows in times of heavy rainfall will put too much flow through the tank, which will likely upset the correct functioning of the system, and wash high levels of suspended solids into the leachfield, risking blocking it.

Divert Rainwater to a separate soakaway system if no other suitable method for disposal is available.

 

[Gary111]

Thanks for your help guys, presumably that grid is already going to a soakaway I guess then?

 

[Hugh Jaleak]

presumably that grid is already going to a soakaway I guess then?

Gully, I suspect, was a later addition, being plastic, and was installed to take the waste pipe. Should be connected to the foul drainage system, going to the Septic Tank, waste water shouldn't go to a soakaway without treatment of some description.

Rainwater would have been directed elsewhere, as cast rainwater goods would likely be original to the build, and predate the gully. Had gully been meant to take the rainwater it would have been sited under the downpipe and the waste run across to it, rather than vice versa.

 

[Madrab]

Yep, the reason the shoe is in the orientation it is, is to direct the surface water into the ground and whoever directed it into the gully obviously didn't know better. Ideally there would have been a depression formed into that cement in the direction the shoe is pointing to allow the rain water to run to a place where it woudl soakaway into the ground.

What's down beyond that bit of concrete? Can the water be channeled to a spot where it would just disperse? I'd be tempted to cut a bit of that concrete out, drop a channel drain in and take the water away to a small soakway cut into the ground.

 

[Gary111]

Ahh ok so I am still ok to connect that to the grid then?
It's the only downpipe for the 4 houses if that makes any difference

 

[Madrab]

No, depending on what is out if the bottom part of that picture. if it garden/soil then you would keep the downpipe and shoe the same, cut that channel into the concrete as if it was heading out the bottom of your picture and then into a hole cut in the ground where the water can soak away, again if there is soil out of the bottom of the picture. You don't water surface water heading into the gulley and then into the sceptic tank.

 

[Hugh Jaleak]

Ahh ok so I am still ok to connect that to the grid then?
It's the only downpipe for the 4 houses if that makes any difference

No. It needs directing to a soakaway, or somewhere the water will disperse. Rainwater should always be excluded from a Septic Tank, especially if it's 4 houses worth! Putting that lot through a Septic Tank, as I said above, will cause major issues over time!

 

[Gary111]

There's a small lawn, seems like all that water would make it a bit soggy though?

 

[Gary111]

Thanks for all your help, what size soakaway would I need?
Is there any way to tell if there already is one?

 

[Hugh Jaleak]

Doubtful there anything existing or I'd expect the downpipe to already be going to it. Percolation Test would be needed to ascertain how quickly water will disperse into the ground and go from there.