Water Leak on My Property UK | Who Pays to Fix It

Ofwat opened a consultation on 27 August 2026 to overhaul the methodology water companies use to measure and report leakage. It closes 9 October 2026. The framework it's replacing has been largely unchanged since 1994, which is itself a mildly staggering fact when you consider how much the water industry, the regulatory environment, and the age of the buried pipe network have all shifted since then.

At the same time, Thames Water has been publicly repairing over 1,000 leaks a week across its Greater London network. That figure landed in August 2026 and caused a predictable round of newspaper headlines. The framing was almost entirely about Thames Water's own infrastructure: its mains, its rising mains, its joints. The bit that got buried, if you'll excuse the phrasing, was the explicit mention in Ofwat's consultation document of customer supply pipes.

That's where Kingston upon Thames homeowners, landlords, and small business owners need to pay close attention.

What the Consultation Is Actually About

Ofwat's review is not purely a statistical tidying exercise. The stated aim is to create a leakage reporting methodology that is more consistent, more auditable, and better aligned with what regulators actually want to measure heading into the 2029 price review. Water companies will be required to account for leakage more rigorously across all pipe categories, including the category that includes your supply pipe.

The 2029 price review is the mechanism by which Ofwat sets what water companies can spend and charge. If the new methodology assigns more measurable leakage volume to customer supply pipes, that affects how companies like Thames Water model their network losses, how they report their performance against leakage targets, and potentially how they approach liability and repair responsibilities at the boundary.

None of that translates directly into a law that lands on your doorstep next April. But the regulatory framework that gets set now shapes enforcement, insurance practice, and the conversations you end up having with Thames Water in three years' time when there's a soggy patch on your front path.

The Supply Pipe Boundary: Who Owns What

This is the bit that causes genuine confusion, and it's worth being blunt about it.

Under the Water Industry Act 1991, the supply pipe, meaning the section of pipework that runs from the street main into and through your property, is legally your responsibility. Not Thames Water's. Yours.

The boundary point is generally the stop tap, sometimes called the stopcock, at or near your property boundary. Thames Water owns and maintains the communication pipe from the main up to that point. Everything from the stop tap inward, including the pipe that runs under your front garden, under your foundations, through your kitchen, and up to every tap in the building, is yours.

Here's a simple version of that boundary:

Thames Water will sometimes repair supply pipe leaks as a goodwill measure, or under specific schemes for vulnerable customers. But there is no general obligation on them to do so, and you should not assume that because a leak is close to the pavement it's their problem.

If your home insurance covers water escape, check whether it includes supply pipes. Many policies do, but with excess levels and exclusions that make claiming less attractive than it first looks. Some policies exclude supply pipes entirely if the pipe is over a certain age or material type, particularly old lead or iron runs.

Why Kingston upon Thames Is Specifically Exposed

The KT1 and KT2 postcodes cover a housing stock that ranges from Victorian and Edwardian terraces in Norbiton and Canbury, through 1930s semis in Tolworth and Long Ditton, to larger properties on Kingston Hill and in Coombe. A significant proportion of that older housing stock has never had its supply pipes inspected, let alone replaced.

Lead supply pipes in properties built before the 1970s are not unusual in this area. Iron pipes from the same era are common in commercial premises along the town centre and in Hampton Wick. Plastic replacement pipes laid in the 1980s and 1990s are ageing now too, particularly where they were laid through clay-heavy ground that moves seasonally, which describes a lot of the soil profile across Kingston, Surbiton, and Ham.

Neither CCTV surveys nor acoustic leak detection were widespread in domestic drainage and supply work until relatively recently. The result is that a large number of homeowners in this area have no idea what their supply pipe looks like, what material it's made from, whether it has micro-fractures developing, or whether the ground movement over the past few winters has started to open joints.

Thames Water fixing 1,000 leaks a week across Greater London sounds impressive. It is also a useful reminder of just how many leaks exist, and the vast majority of those will be on mains and communication pipes. The supply pipes, the ones that are your responsibility, aren't in those numbers at all.

What Ofwat's New Methodology Could Change

The honest answer is: we don't know yet, because the consultation hasn't closed and the final methodology won't be confirmed until later in the process.

What the consultation document does make clear is that Ofwat wants better visibility of leakage across the whole network, including customer supply pipes. At present, supply pipe leakage is estimated using models rather than measured directly. Improving the methodology means improving how that estimate is calculated, and possibly how it's attributed.

If regulators and water companies start measuring supply pipe leakage more precisely, there are a few plausible downstream effects for homeowners:

• Water companies may become more proactive in notifying customers of suspected supply pipe leaks, because the data will be cleaner and more visible.
• Leakage targets may become harder to hit if supply pipe losses are better captured, which could increase regulatory pressure to push responsibility for repair back toward property owners.
• Thames Water's customer contact approach may shift, from a general advisory to something more formal when they detect anomalies on a supply pipe.
• Property transactions could increasingly require documentation of supply pipe condition, in the same way that drainage searches already flag adoptable sewer positions.

None of that is certain. But all of it is plausible, and the consultation closing date of 9 October 2026 means the methodology will be firmed up well before most Kingston homeowners have given it a second thought.

The Practical Argument for a CCTV Survey Right Now

I run CCTV drain surveys for a living, so you can factor that in when you read this. But the argument is still sound.

A CCTV survey gives you a documented baseline of your pipe condition. The camera doesn't guess: it shows cracked joints, root ingress, pipe displacement, corrosion, build-up, and any active infiltration. For supply pipes as opposed to drainage pipes, specialist equipment and access points are required, and the survey methodology differs, but the principle is the same. You know what you've got.

That matters for a few reasons that are specifically relevant to the Ofwat consultation:

Before any new methodology locks in, you want evidence. If a regulatory change creates a situation where Thames Water can point at your supply pipe and argue that it's contributing to network leakage losses, having a survey conducted in 2026 that shows your pipe was in good condition is useful documentation. It's much harder to reconstruct that evidence after a dispute has started.

Insurance claims go better with prior documentation. If you subsequently discover a leak and claim on your home insurance, a survey record showing the pipe was sound at a known date strengthens your position considerably. The alternative is arguing about whether the damage was pre-existing.

For landlords, it's part of your duty of care. If you own rental property in Surbiton, Teddington, or Kingston Town Centre and something goes wrong with a supply pipe that you could reasonably have identified, the question of what you knew and when becomes relevant. A periodic survey is defensible evidence.

For businesses, the stakes are higher. A supply pipe leak under a commercial premises in a Kingston town centre unit can mean business interruption, structural damage to a rented floor, and a dispute with your landlord about who bears the cost. Commercial drainage contracts typically include supply infrastructure checks for exactly this reason.

What a CCTV Survey Won't Tell You (and What Will)

A CCTV drain survey is specific to what the camera can access and what it can image. For drainage pipes, that's generally straightforward: manholes, rodding eyes, inspection chambers, and push-camera access. For supply pipes, you're in slightly different territory because the pipe is under pressure and lacks the same access points.

For supply pipe condition assessment, acoustic leak detection is often used alongside or instead of camera inspection. It detects the sound signature of water escaping under pressure through a crack or joint failure. It requires access to the stop tap and ideally to internal fittings. A specialist drainage and leak detection company can combine both methods to give you a thorough picture.

For drain pipes, which is most of what we survey, the CCTV camera will show:

• Root ingress (common under mature gardens in Ham, Coombe Hill, and Kingston Vale)
• Cracked or displaced pipes (often the result of ground movement or vehicle loading over shallow-laid runs)
• Bellying, where a pipe section has sagged and holds standing water
• Joint displacements common in clay-jointed Victorian brickwork
• Infiltration, meaning groundwater entering the pipe through defects

Your drains and your supply pipe are separate systems, but the underlying risks, ground movement, age of materials, root activity, are the same. If a CCTV survey shows your drains are in poor condition for a 1930s Surbiton semi, it's a reasonable inference that the supply pipe installed around the same time and through the same ground warrants a closer look.

The Regulator's Timeline and Yours

Ofwat's consultation closes 9 October 2026. The 2029 price review process runs from here. In regulatory terms, that's not long. In homeowner terms, it tends to feel abstract until it isn't.

The supply pipe boundary has been in the Water Industry Act since 1991. It's not going to change. What may change is how actively water companies are required to report and account for the leakage that happens on that side of the line, and how visible that information becomes to regulators, insurers, and conveyancers.

Getting ahead of that, with a survey on record and an honest understanding of what you own and what condition it's in, is straightforwardly sensible. It's not a dramatic action. It's the kind of thing you do before a regulatory shift solidifies, not after.

Kingston upon Thames has older housing stock, clay-heavy ground, and a water network that Thames Water's own figures confirm is under significant stress. That combination is not a reason for alarm. It is a reason to know what's under your front path.

Drainsco covers Kingston upon Thames and the full range of KT postcodes, with engineers available 24 hours a day. We'll give you a clear price before we start, and there's no call-out fee. If you want a CCTV drain survey to establish your drainage pipe condition, or advice on next steps for supply pipe assessment, call us and we'll talk through what's involved.