By Danny Ozoum, drainage engineer, Drains 4 Brighton. Updated 2026.
Quick answer
In most cases you, the property owner, are responsible for blocked drains inside your property boundary. Your water and sewerage company, which is Southern Water across Sussex, is responsible for the public sewers and, since 2011, for most shared and lateral drains outside your boundary.
So a blockage in the pipe running from your own kitchen or bathroom to the edge of your property is yours to sort out. A blockage in a shared pipe serving several homes, or in the public sewer, is usually Southern Water's. That single distinction, private drain against shared or public sewer, decides who pays.
Drain, lateral drain or sewer: what's the difference?
The words matter here, because they decide responsibility.
A drain is a pipe that serves only your property. It is yours, and it sits inside your boundary.
A lateral drain is the section of your drain that runs outside your boundary, under the pavement or road, before it reaches the public sewer. Since 1 October 2011 most lateral drains have belonged to the water company.
A sewer is a pipe that serves more than one property. Most private sewers also transferred to the water companies in 2011 and are now Southern Water's responsibility.
What changed in 2011?
Before October 2011, shared private sewers and lateral drains were the joint responsibility of the homeowners connected to them. That caused endless arguments between neighbours over who paid for what. On 1 October 2011, ownership of most of those shared and lateral drains in England and Wales transferred to the regional water and sewerage companies. In Sussex that means Southern Water.
What that means in practice: if the blockage is in a pipe shared with your neighbours, or beyond your boundary, it's usually not your bill.
Am I responsible if the blockage is on my property?
Yes. A blockage in the drain that serves only your home, within your boundary, is the property owner's responsibility. That covers the gully outside your kitchen, the soil pipe from your toilet, and the drain run across your own garden. This is the everyday blocked drain we clear for homeowners across Brighton and Sussex: sinks, toilets, outside gullies and single-property drains.
My outside drain is blocked. Whose is that?
The most common version of this question, and the answer depends on what the pipe does after it leaves your gully rather than on the fact that it is outdoors.
The gully itself, the grid outside your kitchen or bathroom waste pipe, is yours. So is the underground run leading away from it, for as long as that run only serves your house. Silt in the gully pot, leaves packed under the grate, fat setting in the first few metres: your pipe, your bill, and often something you can clear yourself. There is a step-by-step guide in clearing a blocked outside drain.
It stops being yours at the point the pipe joins something shared. Once your run meets a drain carrying waste from a neighbouring property, that section is a lateral drain or a private sewer, and since 2011 it has almost certainly belonged to Southern Water. The same applies to anything beyond your boundary line.
Three signs the blocked outside drain isn't yours:
- Neighbours are having the same trouble at the same time.
- The inspection chamber where it backs up sits outside your boundary, or takes pipes arriving from more than one direction.
- Your house is in an older terrace. Around Brighton and Hove, one Victorian run serving four or five houses is normal rather than unusual.
If any of those apply, ring Southern Water before you pay anyone. They will confirm whose pipe it is, and if it turns out to be theirs, they will often clear it for nothing.
When is it Southern Water's responsibility?
Contact Southern Water rather than us when:
- The blockage is in a public sewer.
- The pipe is shared with other properties, meaning a shared or private sewer that transferred in 2011.
- The problem is in the lateral drain beyond your boundary.
- Several homes in your street are affected at once, which is a strong hint that it is a shared or public pipe.
They can inspect and clear these, often at no cost to you. If you're not certain whose pipe it is, Southern Water can tell you, and it's worth two minutes on the phone to them before you pay anybody for private work on a pipe that isn't yours.
What about rented properties?
If you rent, report a blocked drain to your landlord or letting agent first. Clearing blockages within the property is normally the landlord's responsibility, unless your tenancy agreement says otherwise and the blockage was caused by misuse, meaning wipes, fat or foreign objects down the pipe.
Still not sure? We'll tell you honestly
Working out whose drain it is gets confusing, particularly with the older shared Victorian drainage under so many Brighton, Hove and Sussex terraces. Call 07404 434534 and we'll help you work out whether it's your drain or one for Southern Water. If it's yours, we can clear it there and then.
We only take on blocked-drain clearance that's genuinely your responsibility. We won't charge you to clear a pipe Southern Water should be dealing with for free, and we'd rather tell you that on the phone than after you've paid us.
Need a blocked drain cleared now? Call 07404 434534, 24/7 across East Sussex and West Sussex, or see our main blocked drain clearance page.
This guide is general information for Sussex, England. For the definitive position on a specific pipe, confirm with Southern Water.