Hi all, Is there any legal requirement regarding the depth of 5" plastic drains in a house's back garden? I've just acquired a property where a pipe run has been left only partially buried in shallow trenches. I guess the owner planned to raise the surface of the surrounding ground. I have now raised the level of the surrounding ground using broken concrete blocks, (which needed disposing of anyway). If I then make sure the drains (and broken blocks are covered by 4" of crushed limestone aggregate, is that sufficient? Is that a suitable material to cover the work with? Part of the pipe run is for sewerage and part is for rainwater drainage which runs unto the sewerage section.
The drain is close to the back of the house, so no vehicles are likely to drive over them, except at one section, which is the rainwater drainage section. Should I encase the drain in concrete at that section?
Thank you, Alan