Drains and Sewers

Many homeowners may not realise that they have the responsibility for the repair or maintenance of drainage pipework related to their property. This information is intended as brief guide to explain sewers and drains and who is responsible for them in different situations. It is not a definitive statement of the law.

There are three main terms used to describe underground drainage pipes and these descriptions will usually determine who is responsible for the repair and maintenance of the pipe in question.

• A drain is a pipe that carries waste water (foul or surface water) from just one property. This drain is the sole responsibility of the owner(s) of that property for the full length up to the point where the pipe either connects to another pipe, or another pipe connects to it. At this point it becomes a sewer.

• A public sewer is a pipe that is the responsibility of the Sewerage Undertaker for the area. In Three Rivers District this is Thames Water Utilities. These pipes have either been "adopted" by Thames Water since they were laid, or they are pipes which connect two or more properties to the public drainage system and the pipes were in use for this purpose before 1 October 1937. The waste water from every property connected to mains drainage will eventually flow into a public sewer, before reaching its final treatment point. Thames Water keeps plans of public sewers and they can be contacted on telephone number 08459 200800.

• A private sewer is any pipe, taking waste water from more than one property, which is not a public sewer. This sewer is the joint responsibility of each of those properties that drain into it. This responsibility continues up to the point where the private sewer (including the connection) joins a public sewer after which point the responsibility then changes to Thames Water. This means that often people are responsible for the repair and maintenance of drainage pipes that are beneath land owned by someone else. The Council does not normally keep records of private sewers. All cesspits, cesspools and septic tanks are a private responsibility.

If you have a problem and, depending on the responsibility for the blocked pipe, the following action is suggested:

• If the blocked pipe is a drain, you are responsible for sorting out the blockage. Drain rods, hired from a tool hire shop, can sometimes sort out the problem. Specialist contractors can be found in the Yellow Pages under "Drain and Pipe Cleaning" and many offer a 24 hour service.

• Where the blocked pipe is a private sewer, the same procedure can be followed. However, the cost of the required works should be shared equally between all households that drain into the affected part of the sewer. It is important to know who is served by the sewer. You should agree to share the cost of the works before arranging for a contractor.

• If the blocked pipe is a public sewer, Thames Water will clear the blockage free of charge. Their Customer Services Line is 0845 9200800. If regular blockages occur in any pipe, this may be due to a defect in the pipework such as a collapsed pipe, a bad joint, tree roots growing in the pipe etc. If this is the case, the affected area of pipe may have to be dug up and properly re-laid. The responsibility for the cost of carrying out the work will be the same as it would for clearing a blockage. 

In order to identify the nature of a problem and its location, it is often necessary to carry out a Closed Circuit Television (CCTV) survey of the affected pipework. Many specialist drainage contractors can carry this out for you. Where a problem is identified with a private sewer and the households responsible for repairs or maintenance cannot co-operate to have the works carried out, the Council have legal powers to serve a statutory notice requiring works on those responsible. If the work is still not carried out, the Council's Environmental Health Section can then carry out the work and recharge those responsible for the cost.