Is the water company responsible for my blocked drain?

Water companies are responsible for public sewers, which typically start at the property boundary. Private drains within your property boundary are your responsibility. Since 2011, most lateral drains transferred to water company ownership.

How do I find out if my drain is private or public?

Contact your local water company to check sewer maps. Generally, drains within your property boundary are private. Shared drains serving multiple properties are usually public sewers.

Will my water company fix a blocked drain for free?

Water companies investigate and clear blockages in public sewers at no charge. If the blockage is in your private drain, you are responsible for the cost.

What changed in 2011 for drain responsibility?

The Private Sewers Transfer 2011 moved ownership of most lateral drains and shared sewers to water companies. If your lateral drain was built before July 2011, it's likely now the water company's responsibility.

Who is Responsible for Drains? Water Company vs Homeowner

Understanding who is responsible for drainage problems can save you time, money, and frustration. This guide explains the rules for England, Wales, Scotland, and Northern Ireland.

Quick Answer Your water company is responsible for public sewers (usually outside your property boundary). You are responsible for private drains within your property. Since 2011, most lateral drains connecting to the main sewer are the water company's responsibility.

The Key Rule: Property Boundary

The general principle is simple:

Inside your boundary = Your responsibility (private drain)
Outside your boundary = Water company's responsibility (public sewer)

However, there are important exceptions due to the Private Sewers Transfer 2011 legislation.

What Changed in 2011?

Before October 2011, many drains were privately owned even if they were outside your property or shared with neighbours. The Private Sewers Transfer transferred most of these to water company ownership.

2011 Transfer Rule If your lateral drain (the pipe connecting your property to the main sewer) was built before 1 July 2011 and serves more than one property, it's now the water company's responsibility—even if it runs through your garden.

What YOU Are Responsible For

Internal drainage (sinks, toilets, baths, showers)
Drains serving only your property within your boundary
Any drains built after 1 July 2011 that haven't been adopted
Septic tanks and treatment plants (if not connected to mains)
Rainwater drainage on your property (gutters, downpipes, soakaways)

What the WATER COMPANY Covers

Public sewers in roads and public areas
Lateral drains (connecting pipes to main sewer) for pre-2011 builds
Shared drains serving multiple properties
Any drain adopted into the public sewer system

Contact your water company to check their sewer maps if you're unsure.

Regional Differences

England & Wales

The 2011 transfer applies. Water companies include Thames Water, Severn Trent, United Utilities, Yorkshire Water, Southern Water, and others. Ofwat regulates these companies.

Scotland

Scottish Water handles all public drainage. Similar rules apply—private drains are your responsibility, public sewers are theirs. Contact Scottish Water to check your drainage responsibility.

Northern Ireland

NI Water manages public drainage. The principles are similar, but check with NI Water for specific guidance on your property.

What To Do If You Have a Blockage

Identify the location — Is it inside your property or affecting the street/neighbours?
Check multiple fixtures — If only one drain is affected, it's likely your responsibility
Contact your water company — They can investigate free of charge and tell you who's responsible
Get a CCTV survey — If it's your drain, a survey will show exactly what's wrong