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Drains and sewers: the difference

Drains take foul sewage (waste from toilets, bathrooms and kitchens) and surface water (rain water) away from a single property. Lateral drains are the part of a drain outside the property boundary - for example, in a neighbour’s garden or in the highway.

Sewers are shared drains. They take sewage and water away from more than one property.

Who is responsible for drains and sewers?

Responsibility for drains and sewers lies with different people.

Responsibility for drains

Homeowners or occupiers are responsible for a home’s drains up to their property boundary. If you're responsible for maintaining drains, you may be covered by your house insurance for any damage.

Responsibility for sewers

Water and sewerage companies are responsible for:

• all public sewers
• private sewers and lateral drains that connect to the public sewer

Water and sewerage companies are not responsible for private sewers that:

• are connected to a private pumping station and treatment works
  
• carry water directly to a watercourse, like a river, or into the ground (for example, a soakaway)

The Consumer Council for Water website has diagrams showing who is responsible for what.

• Contact your water company: Consumer Council for Water Opens new window

• Transfer of sewers to water companies: Consumer Council for Water Opens new window

Reporting a blocked drain

If your drain becomes blocked, you usually know because your waste stops going away when you flush the toilet. Manholes and gullies (drainage gratings) may also start to overflow.

If there is a nuisance smell or blockage, contact your council’s environmental health department. This has powers to carry out repairs and recover costs from the home owner.

Your council may also be able to give you advice if a neighbour’s drain is blocked and causes water to enter your property.

If you find a blocked gully, grating, ditch or drain that causes road flooding, use the link ‘Report road flooding’.

• Find out about blocked drains Opens new window

• Report road flooding Opens new window

Preventing a blocked or damaged drain

You can help stop drains and sewers becoming blocked or damaged.

Dispose of waste properly

When substances other than waste water are flushed down the drain, this can cause problems. For example, fats and oils can solidify and cause smells. The following items mustn’t be flushed down the drain:

• waste food
  
• paints and solvents
  
• fats, oils and greases
  
• disposable nappies and wipes
  
• condoms
  
• sanitary products
  
• bandages and dressings
  
• animal waste
  
• cotton wool and cotton buds
  
• razor blades
  
• fuel

Take care with building work

You’re legally required to tell your local authority building control department of building work or works to repair, reconstruct or change the course of a drain.

You should also:

• always allow a working zone around drains for repairs and maintenance
  
• make sure building work doesn’t damage the drain or sewer by direct contact with pipe work
  
• not displace surrounding material that supports and protects the pipe work

• Drains and sewers: planning permission (Planning Portal) Opens new window

Be careful making new connections to drains

Foul and surface water drains and sewers are usually separate systems, particularly for houses built in suburban areas after 1950.

Be careful to connect to the correct drain or sewer if:

• you make a new connection
  
• you change the plumbing arrangements of your house (for example, the outflow from a washing machine)

If you put foul matter into a surface water drain, you will cause pollution and might be prosecuted. If you connect surface water drains to a foul sewer, you might contribute to sewer flooding.

You need to notify the water and sewerage company if you intend to connect to any of the sewers or drains for which they are responsible.

Plant vegetation away from drains

Keep vegetation away from drains and sewers if possible. In general, where a pipe is less than one metre deep:

• route new drains and sewers at least three metres from existing trees
  
• plant new trees at least three metres from an existing sewer
  

Where a pipe is more than one metre deep, the distance can be reduced to two metres.

For further advice about locating trees, contact your council's tree officer.

• Find your local council Opens new window

More useful links

• Water: using less at home (environment and greener living section)

• Recycling (environment and greener living section)

Useful contacts

• Home and community contacts