The responsibility for a length of drainage pipe is determined by reference to the ownership of the property or properties it serves. This rule applies even where the pipe passes through land in another ownership, for example, a neighbour's garden or a public road or footpath*.
A drain serves one property only or buildings within the same curtilage and the cost of clearing it and carrying out any necessary repairs is payable by the owner. The council can serve legal notice requiring an owner to cleanse or repair a blocked or defective drain.
A sewer serves two or more separate properties.
Public sewers which form part of the main sewerage system of the borough are cleansed and maintained by Severn Trent Limited.
Also, certain "combined drains" serving private properties constructed before 1937 were legally classified as public sewers. Public sewers are normally in publicly accessible areas, but some may run under private gardens.
*The legal provisions are contained in the Public Health Acts 1936 and 1961, Local Government (Miscellaneous Provisions) Acts 1976 and 1982, the Building Act 1984 and the Water Act 1989.