Severn Trent Bill Rise 2027 | What It Means for Your Drains

Severn Trent is getting more of your money. Again.

On 13 August 2026, Ofwat published its Cost Change 2026 Draft Determinations, provisionally approving £3.4 billion of additional investment across thirteen water companies. Severn Trent is one of five companies allowed to start recovering those extra costs from April 2027. The initial hit is modest on paper: roughly £3 more per year per household. By 2030 that figure rises to around £5. But layer that on top of the approximately 10% bill increase that landed in April 2026, and the picture becomes less comfortable.

Ofwat's consultation closes on 24 September 2026. Final decisions come in December. So unless you respond to the consultation or something unusual shifts in the process, April 2027 is the date to write in your diary.

What the Money Is Actually For

This isn't a single neat project. The approved funding covers a wide range of work: storm overflow improvements, wastewater treatment capacity upgrades, leakage reduction and network resilience. Severn Trent covers a vast area from the Midlands down through Gloucestershire, so the specific projects earmarked for the GL7 patch haven't been named individually in the draft determination. What Ofwat has confirmed is that a meaningful proportion of the extra spend goes toward wastewater infrastructure.

For context, Severn Trent's existing price review (PR24) had already set out a significant capital programme. This Cost Change process is a supplementary mechanism allowing companies to recover costs that have moved materially since the original determination. In plain terms: it went up more than expected, and you're paying the difference.

Is that fair? I think that's the wrong question. Whether it's fair or not, it's happening. The more useful question is what it means in practice for homeowners and businesses in and around Cirencester.

The Bit Severn Trent Won't Tell You

Here's the thing that rarely gets into the press coverage of these announcements. All that investment, the treatment works upgrades, the overflow improvements, the network resilience, covers Severn Trent's assets. Their pipes. Their infrastructure.

Your drains aren't on that list.

The lateral drain beneath your garden in Stratton, the stack running down the back of your terrace in Watermoor, the grease trap under the floor of your kitchen on the high street, those are yours. Private. Severn Trent's responsibility ends at the public sewer connection. Everything upstream of that point is your problem to inspect, maintain and repair.

This matters because the public network improving doesn't help much if the private lateral feeding into it is cracked, root-invaded or partially blocked. I've seen plenty of jobs in Siddington, Coates and Kemble where the homeowner has been watching a slow drain for months, assuming it was a public network issue. It rarely is. Most blockages and most structural failures happen in the private section.

What Rising Bills Actually Incentivise

When bills go up, people pay more attention to what they're getting for the money. That's not unreasonable. But attention directed purely at Severn Trent's spending misses the parallel obligation on the homeowner's side.

A CCTV drain survey on a typical three-bedroom house in Chesterton or The Beeches takes less than an hour and gives you a recorded view of exactly what's happening inside your private drains. You find out whether there's root ingress from a boundary hedge. Whether a joint has opened up. Whether the previous owners were putting things down the drain they shouldn't have, and the grease has silted back two metres into the run.

Compared with the remedial cost of a failed lateral, which can run from several hundred to several thousand pounds depending on whether it needs relining or digging out, a survey is the cheaper option by a significant margin. And if it comes back clear, you've got documentation. Useful if you're a landlord trying to establish condition between tenancies, or a business owner keeping on top of maintenance records.

For commercial tenants and property owners on Tetbury Road, Lewis Lane or the trading estates off the A419, blocked or failing drains stop business. A restaurant can't trade with a backed-up kitchen drain. A food unit that floods its yard has an environmental and legal exposure, not just a plumbing problem. Preventative jetting, scheduled every six or twelve months, costs a fraction of an emergency call-out at 11pm on a Friday.

Planned Versus Reactive: The Real Cost Comparison

I'm not going to pretend a maintenance contract is right for every property. A single-tenancy house in South Cerney with modern plastic drainage, no mature trees nearby and sensible waste habits probably doesn't need a standing contract. A reactive call-out if something blocks is fine.

But a Victorian terrace in the older streets off Cricklade Road, with clay pipe runs, overhanging elms and forty years of accumulated scale? That's a different calculation. High-pressure water jetting once a year and a CCTV check every couple of years is almost certainly cheaper over a ten-year horizon than the emergency call-outs and patch repairs that happen when you don't.

The same logic applies to any commercial kitchen, any block of flats, any pub or restaurant processing food waste daily. You're not maintaining the drains out of sentimentality. You're managing downtime risk.

The Practical 'So What' for Cirencester

Ofwat's approval of extra Severn Trent investment is genuinely welcome, to the extent that ageing wastewater infrastructure in the region needs serious capital expenditure. The storm overflow issues around Gloucestershire are real and the money needs spending.

But paying more on a Severn Trent bill while ignoring your own private drains is a bit like paying your building insurance premium while leaving a slow roof leak unrepaired. The public infrastructure improving doesn't protect your lateral. Only you can do that.

If you haven't had a CCTV survey done, and you've owned the property more than a few years, it's a reasonable thing to organise. If you run a food business and you're jetting reactively rather than on a schedule, the maths probably don't favour you.

Drainsco covers Cirencester and the wider GL postcodes, with engineers on call around the clock. There's no call-out fee. You get a clear price before any work starts. If repairs or relining are needed, that work carries a 20-year guarantee. Give us a ring and we'll tell you honestly whether a survey or a maintenance visit makes sense for your situation, or whether you're fine as you are.