Help with basic drainage

[fury84]

I had to replace the downpipe from my garage roof but the original ran below the patio. Wanting a tidy job, I decided to remove a patio slab and join below the ground but have ran into difficulty!

I followed the pipe to the bottom where it went into this:

I noticed the side was damaged or I damaged it whilst digging so thought I best find the bottom of this and replace that too. I managed to remove this pipe but the bottom was full of grit and so is the connecting pipe it joins into.

I am not sure where the connecting pipe goes but know it continues down for at least another foot and this too is full with grit. I’m not even sure if it joins the drains or not. Could this be a soakaway that has blocked up over time?

I’m now a little unsure what to do; I’m guessing the pipe should not be filled with grit/gravel? I certainly can’t see an easy way of unblocking it.

Do I just leave the remaining pipe how it is and install a soakaway away from the house?

Any suggestions greatly appreciated.

 

[Richard C]

If it’s a just a surface water connection from your garage roof guttering & there are no foul smells wafting up from the pipe I would think it’s fairly safe to assume it leads to a soak away somewhere but must admit it goes down rather a long way; can you establish how much deeper it goes? Are there are inspection hatches nearby?

Clues to the possible location of a soak away may be from the location of other down pipes on the same side of the property; there are usually least one at the front & another at the back of the property. Chances are the down pipes teed together underground & then went off to the soak away. The way it’s silted, my guess is that particular leg hasn’t been working too well anyway but its anyone’s guess what the rest of it is like unless you fancy even more digging. I had a similar problem with 40 year old underground works 4 years ago. We went straight through two clay pipe feeds whilst building new cons. foundations so I just abandoned them, constructed 2 new soak aways & laid some modern plastic pipe to feed them.

Connecting surface water to the mains drainage system is now rarely permitted by water authorities so you need to construct a new soak away. To comply with Building Regs. it must be a minimum of 5m from the property foundations &, strictly speaking, it’s notifyable work & subject to inspection & a fee.

 

[fury84]

If it’s a just a surface water connection from your garage roof guttering & there are no foul smells wafting up from the pipe I would think it’s fairly safe to assume it leads to a soak away somewhere but must admit it goes down rather a long way; can you establish how much deeper it goes? Are there are inspection hatches nearby?

Clues to the possible location of a soak away may be from the location of other down pipes on the same side of the property; there are usually least one at the front & another at the back of the property. Chances are the down pipes teed together underground & then went off to the soak away. The way it’s silted, my guess is that particular leg hasn’t been working too well anyway but its anyone’s guess what the rest of it is like unless you fancy even more digging. I had a similar problem with 40 year old underground works 4 years ago. We went straight through two clay pipe feeds whilst building new cons. foundations so I just abandoned them, constructed 2 new soak aways & laid some modern plastic pipe to feed them.

Connecting surface water to the mains drainage system is now rarely permitted by water authorities so you need to construct a new soak away. To comply with Building Regs. it must be a minimum of 5m from the property foundations &, strictly speaking, it’s notifyable work & subject to inspection & a fee.

Many thanks for your reply Richard, some great advice there already.

The drain I have been digging is just for my garage roof and thinking about it there is an inspection hatch nearby which I shall lift and see where things are coming from. There are no smells either.

The house which was built in 1970 but I have only recently bought it.

The only way to establish how much deeper it goes, is to dig more, which is possible. I was just worried about damaging the garage foundations.

To help explain where other drains are I have used this diagram:

Point 1 shows the drain I am digging.

Point 2 shows where the kitchen waste drains.

Point 3 shows the down pipe for the main house.

Point 4 shows the internal soil pipe.

I will look for the man hole and dig a little deeper.

If you have any other ideas please post them for me.

Thanks again