South West Water Said I have A Leak What Do I Do

Reviewed by the DCI Leak Detection team · Last updated June 2026

A letter or text from South West Water saying you have a leak is unsettling, especially when you can't see any water. Most of these notifications are about a hidden leak on your private pipe, and there's a clear path through it. Confirm it, work out whose responsibility it is, repair it in time, and claim back what you can. This guide covers what the notice means, what you're responsible for, the financial help on offer, and the steps to take now.

What the South West Water notification actually means

South West Water monitors how much water flows to each property. When it sees a continuous, higher-than-usual flow, water running even when nothing in the house is being used, it flags the property and gets in touch. That contact can be a friendly heads-up or a formal legal notice, and it's worth knowing which you've received.

A courtesy notification alerts you that usage looks high and suggests you investigate. A formal notice under Section 75 of the Water Industry Act 1991 is a legal document requiring you to repair a leak on your pipework within a set period. According to the Water Industry Act 1991, a Section 75 notice must give you at least seven days, and if the work isn't done by the deadline the water company can carry it out itself and recover the cost from you. Read your letter carefully and note which type it is. The wording tells you how urgent it is.

Your responsibilities vs South West Water's

The most important question is where the leak is, because that decides who pays to fix it. The split is set out by the Consumer Council for Water and applies across England and Wales:

So when South West Water reports a leak to you, it's normally because the flow points to your supply pipe or internal plumbing. South West Water owns and maintains everything up to your boundary; you own the pipe from there into the house. If the leak turns out to sit on their side of the line, the repair is theirs and free to you, which is why pinning down the exact location matters.

Shared supply pipes, common in terraces and converted properties, are the trickiest, because every connected household is jointly liable wherever the leak actually is. If your notice mentions a shared supply, get the neighbours together early, agree who coordinates the repair, and keep everything in writing.

How long you have to repair it

There's no single fixed deadline. It depends on your notice and how much water is being lost. South West Water commonly allows around 30 days to repair a supply-pipe leak, but the period can be shorter where a substantial amount of water is escaping. A formal Section 75 notice must, by law, give you at least seven days. The figure that counts is the one printed on your letter, so check it and diarise it.

If you genuinely can't meet the deadline, perhaps you're waiting on a contractor or you're unwell, don't go quiet. Call South West Water on 0344 346 2020 and explain. They can often work with you, but only if you're in touch. Ignoring a Section 75 notice is the costly mistake: the company can step in, do the work and bill you, typically for more than your own repair would have cost.

Steps to take today

1. Confirm the leak at your meter. Turn off every tap and water-using appliance, then watch your meter. If the dials are still moving, water is escaping somewhere on your side, which confirms a leak on your supply pipe or internal plumbing.
2. Find your stop tap. Locate your internal stop tap (usually under the kitchen sink) so you can shut the water off quickly if the leak starts causing damage, exactly as you would with a burst water pipe.
3. Call South West Water. Ring 0344 346 2020 to discuss the notice, confirm where they think the leak is, and ask what financial help applies to you.
4. Document everything. Photograph the notice, your current meter reading, your stop-tap location and any visible damp. You'll need this for both the repair claim and any insurance claim.
5. Check your insurance. Ask your home insurer about trace and access cover, which can pay to find a hidden leak and make good the access damage.
6. Get the leak found. If you can't see where the water is going, bring in a leak detection specialist before anyone starts digging or lifting floors. This is the step that prevents wasted, exploratory damage.

The financial help available

This is the part many homeowners miss. South West Water offers genuine help with the cost of dealing with a supply-pipe leak, and if you're metered you can also recover the cost of the wasted water. Here's what's on the table for household customers.

Help towards the repair

• £100 leak repair contribution for homeowners, paid once the repair is confirmed, capped at one payment per leaking pipe. You'll need to send the receipts or invoice.
• £250 pipe replacement subsidy for homeowners replacing the supply pipe in full, where the work is completed within 30 days.
• Up to half an hour of free leak detection with advice. South West Water can help locate the leak in the first instance.

Each of these is verified on South West Water's own leak repair contribution pages. Keep every invoice, because proof of payment is what releases the contribution.

Money back on your bill (the leak allowance)

If you're on a water meter, you can apply for a leak allowance once the leak is repaired. It credits your account for the extra water lost through the leak, covering up to 12 months of excess usage. Apply within six months of the repair, with before-and-after meter readings and your receipts. On a leak that ran for months, this can be worth a meaningful amount, and it's separate from the repair contribution above. We cover the eligibility and application in detail in our guide to the South West Water leak allowance.

South West Water also runs a Priority Services Register offering extra support, including help arranging detection and more flexible deadlines, for customers who are elderly, disabled or have a medical condition. If that applies to your household, mention it when you call on 0344 346 1010.

Insurance and finding the leak

Before any floors come up, two things are worth doing: check what your insurance covers, and get the leak located precisely. Many buildings policies include trace and access cover, which pays to find the source of a hidden leak and to repair the disruption caused by reaching it. Read more in our explainer on what trace and access cover pays for. Call your insurer before work starts and ask whether you can use your own specialist.

Pinpointing the leak first is what keeps the cost down. Using non-invasive professional water leak detection (thermal imaging, acoustic sensors and tracer gas), a specialist can find the exact spot without guesswork, which matters most on buried supply pipes. For leaks on the run between your meter and the house, underground water leak detection traces the pipe and the escape point precisely, so the repair is targeted rather than a dig-and-hope. If the notice came after a surprise on your bill, our guide on a high water bill with no visible leak covers the early warning signs.

Frequently asked questions