depth between manhole cover and sewer

braizy

I have a sewer in the garden that has about 4 courses of bricks between the sewer itself and the manhole cover. The garden is raised in this area and i want to lower it to create a patio. I am the first in a run of three houses so mine is obviously fairly high but the sewer is of course below ground level of the house. Can i lower the manhole cover by removing courses of bricks? or does it need to be this distance between the sewer itself and the cover?

thanks

Alex

Leif

Be careful as there are regulations about sewer pipes. If they are close to the surface, they must be encased in concrete.

Canucklehead

Good morning: take a look here and here.

HTH

Canucklehead

27col

You can remove a course of bricks from the inspection pit (or manhole, as it is more commonly known). The number of courses in an inspection pit is governed by the ground level and the invert level of the drain is governed by how much fall is required to get to the main drain. The two levels,drain and inspection cover, are not related to each other, only to ground level and invert level. the operation of the drain is decided by the fall of the pipes and is nothing to do with the level of the ground surface.