I am having an extension built soon and was wondering if I could cover up a private rain drain manhole cover? I am double sealing the waste manhole drain but didn't want two unsightly covers in my nice new extension and have heard that the water boards aren't even aware where private drains are these days and people are just covering them up, is this legal?
Thanks
Angela

In the UK, right? On private property you can do almostr anything you want but a manhole was installed for a reason. Are you sure this is just for rain and no sewage?

Yes it is in the uk & we do have a separate sewage drain and manhole which we are going to double seal. Just didn't want to have two in the extension.