Under the Landlord and Tenant Act 1985, the landlord has the responsibility to maintain the property, including pipes, drainage and plumbing. However, if a drain does become blocked through your misuse as the tenant then you may be liable for repair costs
If your home is flooded by water or sewage from drains or sewers then legal action can be taken. Remedial action can also be enforced where a drain or sewer becomes prejudicial to health or a nuisance.
Common law in the UK, has developed from the principle that flooding is natural and, as such, no-one can be blamed for causing it. However, gradually the courts have come to recognise that in some cases it is often the neighbouring land use rather than nature that is the cause of the flooding. The effect of this has been to put increasing duties on parties to take action to avoid flooding in the relevant circumstances and the development of a considerable body of case law in relation to flooding