Lost drain for rain downpipe.

[FDK]

We have recently purchased and are in the process of renovating our 1900's semi detatched property. Through the refurbishment we have torn down a poorly built conservatory at the rear of the property.

The rear of the houses gutter drained from the cast iron downpipe onto the roof of the conservatory and then along the conservatory roof into the gutter on the conservatory. Then onto the concrete on the edge of the conservatory.

Now that the conservatory is gone the downpipe just was draining onto the wall of the house. I have temporarily ran a long length of half round guttering to run the water off the concrete ground into the grass in the garden.

Now I have looked along the wall and I can see the marks where the cast iron used to run down the wall to the ground. So would I be right in thinking there is a drain that has been concreted over?

If so would I be able to uncover it to run the downpipe into it again?

Any advice would be much appreciated.

 

[oldbutnotdead]

If you're lucky then the original gulley trap will be hidden under a paving slab or a big plant pot and the run to the foul waste system will be intact. So yes well worth an afternoon digging around....

 

[FDK]

How would I remove the concrete without damaging the drain below?

 

[oldbutnotdead]

Carefully. Angle grinder and diamond disc would be my starter, if it's a typical conservatory the base will only be 75mm thick, even a 4" grinder will cut to 50mm & finish it with a wrecking bar and a hammer in the cuts.
If the gulley has just been buried you may damage it but the actual pipework will be deeper so unlikely to do anything disastrous

 

[FDK]

Thanks for the advice. Would it be worth drilling a pilot hole with a long drill bit to see how far down the concrete goes before I angle grind?

Also how would I know exactly where the edges of the drain are to angle grind?

 

[oldbutnotdead]

If you have an SDS drill then give it a try, won't hurt. If you drill/cut/hammer a foot either side of where the downpipe was and then 18 inches away from the wall you should avoid the actual gulley position (and with luck just be able to lift chunks of concrete out).