TL;DR
You're responsible for the drains within your own property boundary — the pipe from your sinks and toilets out to where it meets the shared network. Beyond that point, the lateral drain and the public sewer became the water company's responsibility under a nationwide transfer that took effect in 2011, so for most of Aldershot that's Thames Water. If you're not sure which side of that line your problem sits on, a CCTV drain survey settles it, or you can just get in touch and we'll help you work out who to contact.
Three types of pipe, three different owners
The confusion around blocked drains almost always comes down to not knowing which bit of pipe is whose. There are three categories:
- Private drain — the pipework entirely inside your property boundary, running from your house to the point it leaves your land. This is yours, full stop, whether it's blocked, cracked or ancient.
- Lateral drain — the section that continues from your boundary to where it joins the public sewer, sometimes running under a neighbour's garden, a pavement, or the road. Despite draining only your property, this section transferred to water company ownership in 2011.
- Public sewer — the larger pipe that collects from many lateral drains and carries everything onward to treatment. This has always been the water company's to maintain.
A blockage doesn't announce which category it's in — that's the whole problem. Symptoms look the same whether the fault is two metres from your kitchen sink or thirty metres away under the street.
Who to actually contact
If the problem is confined to your own property — say, one bathroom is affected and nothing outside the house shows signs of trouble — it's almost certainly a private drain issue, and that's on you to sort. Our blocked drains team can diagnose it, and our drain unblocking service handles the clearance itself: sorting the obstruction, checking for any underlying damage, and advising on stopping it recurring.
If the fault looks like it's further out — an external gully backing up, multiple properties on the same street affected, or a manhole cover with standing water in it — that's more likely to sit in the lateral drain or public sewer, which means it's Thames Water's problem to fix, not yours to pay for. They handle faults in that section at no cost to the homeowner, because it's their asset.
When it genuinely isn't clear which side of the boundary the fault is on, that's where a CCTV drain survey earns its keep — it shows exactly where the blockage sits, and the footage is the evidence you need whichever way it points.
Shared drains: where it gets more complicated
A lot of Aldershot's housing, particularly the dense Victorian and Edwardian terraces near the town centre, was built with drains that serve more than one property before they reach the lateral drain. Two or three houses on a row will often share a single run of pipe running out to the back.
That shared section is still technically a private drain, because it only serves those specific properties rather than the wider network — but responsibility for it is shared between however many houses feed into it. In practice, this usually means the affected households need to agree on a contractor and split the cost between them, which is a more awkward conversation than a straightforward single-property blockage but a genuinely common one on these older streets.
Properties on newer developments — the estates further out towards Farnborough or around the edges of Fleet, for instance — tend to have their own private drain running independently to the lateral connection, so this kind of shared-responsibility situation is far less common there. If you're unsure whether your drain is shared, that's another question a survey can usually answer by tracing the pipe run.
The local picture: Thames Water and Aldershot
Thames Water is the sewerage undertaker across Aldershot, covering North Town, Cargate, Manor Park and the town centre, along with the surrounding towns of Farnborough, Fleet, Ash and Ash Vale. If you're ever unsure who your sewerage undertaker is, it's worth confirming before reporting a fault — most water companies, including Thames Water, have an online postcode checker for exactly this.
For everyone in and around Aldershot, the practical rule holds: inside your boundary is yours, the lateral drain and sewer beyond it is Thames Water's.
If you're not sure which one you've got
The sensible order of operations is straightforward. Notice which fixtures are affected — one bathroom points inward, multiple properties or an external gully points outward. Have a quiet word with neighbours if you can; shared symptoms usually mean a shared or downstream fault, while an isolated problem is almost always internal to your own property. If it's still not obvious, book a CCTV drain survey — the footage shows the blockage's actual location relative to your boundary, which takes the guesswork out entirely. From there, either book drain unblocking for a private-drain issue, or pass the survey findings to Thames Water for anything on their side of the line.
