A Simple Guide to Private, Public and Shared Drains for domestic properties
If you’ve ever spotted a blocked drain and immediately thought, “Surely that’s not my problem…” — you’re not alone. One of the most common questions we’re asked at TWC Draincare is: who owns the drains? And more importantly, who’s responsible for fixing them when something goes wrong?
The answer depends on where the drain is, what it connects to, and how many properties use it. This is a question we get asked all the time here at TWC Draincare, so what’s the answer?
Private Drains: Yours and Yours Alone
A private drain is any pipe that serves just one property and runs within the boundary of that property. This includes drains from your sinks, toilets and showers up to the point where they connect with another drain or sewer.
In the diagram below there are two properties, property 1 and property 2. The green dotted line indicates the boundary line for each property.
The private drains for Property 1 are indicated in red. These are the drain lines that serve that property only and sit within the boundary line for that property.
The private drains for Property 2 are indicated in orange. These are the drain lines that serve that property only and sit within the boundary line for that property.
If a blockage or collapse occurs in a private drain, the responsibility for repair sits with the property owner. That means arranging investigations, unblocking, repairs and any associated costs. It’s not the most exciting thing to spend money on — but at least you’re fully in control of how it’s sorted.
Private drains are the most common cause of recurring blockages, especially where fats, wipes, tree roots or ageing pipework are involved.
Shared Drains: A Problem for More Than One Household
A shared drain (sometimes called a lateral drain) is used by more than one property but hasn’t yet joined the public sewer. These often run across gardens, driveways or under access paths before connecting to the main sewer in the road.
Responsibility for shared drains can be a bit of a grey area. In many cases, once a drain leaves your boundary and connects with others, it should be maintained by the local water authority. However, there are exceptions — particularly with older properties or private drainage systems.
Looking at the diagram, the lateral drains, or shared lines are the ones shown in black. This includes those that are within the property boundary for property 1,but carry waste from property 2.
If there’s a blockage affecting multiple properties, it’s always worth a call to your local water authority as responsibility for the repairs, and unblocking, could sit with them.
Public Sewers: Leave It to the Water Company
A public sewer is maintained by the local water authority and usually runs beneath roads or pavements. This is the line indicated in brown on the above diagram.
If the problem lies in the public sewer, repairs and maintenance are their responsibility — not yours.
That said, determining whether an issue is in your private drain or the public sewer isn’t always obvious from the surface. Water backing up, slow drainage or external flooding can originate from either.
Not Sure Who Owns It? That’s Where We Come In
Drain ownership isn’t always straightforward — especially when shared systems, older properties or hidden pipework are involved. A professional drainage survey can quickly identify where the issue lies.
At TWC Draincare, we help take the guesswork out and provide practical solutions. Because when it comes to drains, knowing whose problem it is, can save a lot of time, stress and unnecessary expense. Get in touch by calling TWC Draincare on 👉 03333 052 243.
