Septic Tank Upgrades

WCI Nutrient Neutrality offers qualifying property owners a completely free septic tank upgrade to a modern, high-performance sewage treatment system.

Developers building new homes in Somerset’s designated catchments must offset the phosphate impact of their developments – a planning requirement called nutrient neutrality.

Your upgraded system creates a measurable phosphate reduction (what experts call “phosphate betterment”) that developers purchase as credits to satisfy this requirement.

The phosphate credits fund your free upgrade. You get a better system. Developers get planning approval. Somerset’s rivers get cleaner water. Everyone benefits.

This is not a government grant. It’s an environmental partnership where infrastructure improvement creates genuine water quality benefits while enabling sustainable development.

WCI Nutrient Neutrality’s Free Upgrade Scheme Somerset, currently operates in properties located within Natural England’s designated nutrient neutrality catchments:

• River Parrett catchment
• River Tone catchment
• River Brue catchment
• River Axe catchment

Open the Interactive Map – Phosphate River Catchments 2025

Not sure if your property falls within these boundaries? Register your interest and we’ll verify your location using Natural England’s official catchment mapping.

Your old septic tank is replaced with a British Water-approved sewage treatment plant designed for your property’s specific needs. These systems use advanced biological treatment to remove over 95% of phosphates before discharge – dramatically reducing environmental impact.

WCI Group’s experienced installation teams complete the work to building regulations standards with minimal disruption to your property. Average installation time is usually 3–5 days.

A WCI Service Engineer commissions your new system and provides clear instructions on operation. You receive manufacturer documentation and emergency contact details.

Your first annual service is included at no cost, ensuring your system starts its life performing optimally.

We restore excavated areas to a basic standard, leaving your property tidy and functional.

Complete our quick registration form. We’ll confirm whether your property falls within eligible catchments and add you to our register.

What happens next? You’ll receive email confirmation explaining the process and typical timescales. We’ll then send updates on scheme progress.

Because upgrades are funded by developer demand for phosphate credits, there’s currently a waitlist. Typical wait time is approximately 12+ months, though this varies by location and developer activity.

While you wait: We can offer maintenance services for your existing septic tank to keep it functioning reliably or discuss paid upgrade options if you prefer not to wait.

When developer demand aligns with your location, we contact you to schedule a free site survey (1-2 hours). Our engineers assess your property, existing system and any site-specific requirements.

You don’t need to be present for the survey, though it can be helpful for questions.

If your site is suitable, we’ll explain the simple agreement (see FAQ below) that ensures the upgraded system is maintained appropriately.

Our installation team arrives with all equipment and materials. We bring portable facilities to minimise disruption during the installation period.

Once complete, your system is commissioned, tested and handed over with full documentation. You’re now protecting Somerset’s rivers with every flush.

1. Immediate email confirmation explaining the next steps
2. Eligibility verification using Natural England catchment mapping
3. Kept updated on scheme progress and developer demand
4. Priority contact when upgrade opportunities arise in your area

Questions while you wait?

Our Nutrient Neutrality team is here to help: 01984 623 404

You may qualify if you meet all of these criteria:

Your property must have overnight accommodation:

• Main residences (houses, bungalows, flats)
• Holiday lets and B&Bs
• Care homes or nursing facilities
• Granny annexes or converted barns with sleeping accommodation

The number of bedrooms determines system size and phosphate offset potential.

Your property must fall within one of the designated Somerset catchments: River Tone, Parrett, Brue or Axe.

We verify location using Natural England’s official catchment boundaries.

The property owner must sign the agreement. Tenants cannot participate without owner involvement.

For leasehold properties, leaseholder and/or mortgage company approval may be required – we can guide you through this.

Even if your tank lies on third party land, we can still upgrade but the new sewage treatment plant will need to be located on your land. The new sewage treatment plant can still discharge into soakaways or streams that are not on your land.

Shared systems can be upgraded. Both you and your neighbour will need to enter into shared legal agreements. Please talk to your neighbours and ensure they also want to upgrade before contacting us as we cannot negotiate with your neighbour on your behalf.

If you want to separate your system from your neighbour, WCI Group can provide a funded sewage treatment plant and separate you from your neighbours under the scheme. However, this implies a new discharge either to ground or to a stream which must be technically feasible. We cannot separate your property from neighbours if it would ‘cut them off’ from the existing system. Register your interest and we will consider the options when we survey your property.

The upgraded system belongs to you, there’s no ongoing payment to WCI Nutrient Neutrality, no hidden fees and no catch. However, like any wastewater system, there are standard responsibilities to keep it working effectively:

Under Environment Agency General Binding Rules, all sewage treatment plants require annual inspection – whether installed through our scheme or purchased privately. Think of it like an MOT for your car: essential maintenance that keeps everything working safely and legally.

• Service frequency: Once per year
• Service provider: Your choice of approved contractor (WCI Service Engineers offers this service, but you’re free to use others)
• Typical cost: Similar to annual boiler servicing

This obligation exists for ANY treatment plant owner under current environmental law – it’s not specific to our scheme.

Like septic tanks, treatment plants accumulate sludge that needs periodic removal.

• Frequency: Approximately every 2–3 years (similar to septic tank emptying)
• Provider: Any licensed waste contractor (you can continue using your existing company)
• Cost: Comparable to septic tank emptying you’re already familiar with

Modern treatment plants require continuous low-power electricity supply.

• Consumption: Equivalent to a standard light bulb running continuously

When you proceed with installation, you’ll sign a document called a Unilateral Undertaking. This legal name sounds intimidating, but it’s simply a formal agreement that:

• You’ll maintain the upgraded system in good working order
• These maintenance obligations transfer to future owners if you sell
• The phosphate reduction achieved by your upgrade remains registered for its design life (typically 80 years)

What “good working order” means:
Following the annual servicing and desludging schedule outlined above. Nothing unusual or burdensome – just the standard care any treatment plant requires.

What happens if you don’t maintain it?
The agreement is a legal deed registered with the council. Failure to maintain constitutes breach of covenant, which councils can enforce – though in practice, proper maintenance is straightforward and problems are rare.

Can you opt out?
Yes, at any point before signing the Unilateral Undertaking. Once signed, you’re committed for the system’s design life. However, if you later sell the property, obligations simply transfer to the new owner (we update our records accordingly).

The survey, equipment, and installation are entirely free. However, transparency matters – here are potential additional costs a small number of situations might involve:

Most property owners proceed without needing solicitor advice. However, if your mortgage lender requires you to instruct a solicitor regarding the Unilateral Undertaking, any legal fees are between you, your solicitor, and your lender.

WCI does not require you to use a solicitor – this only arises if your lender specifically requests it.

If your current foul drainage has a fault requiring repair before the new system can connect (cracked pipes, collapsed drains, etc.), you would arrange and fund that repair separately. Our survey identifies any such issues upfront. No surprises.

Many older septic tanks incorrectly receive rainwater from roof gutters mixed with foul water. Current regulations require these to be separated.

If your existing guttering discharges into your septic tank, you’ll need to arrange diversion to a suitable soakaway before installation begins. This is usually straightforward groundwork.

If installation requires crossing a neighbour’s land beyond our standard access agreement, any additional costs or arrangements are between you and that landowner.

We always discuss foreseeable additional requirements during the survey – no hidden surprises.

The upgraded system and maintenance obligations transfer to the new owner when you sell. This does not negatively affect property value or saleability – you’re transferring a modern, compliant wastewater system, which is typically viewed positively.

Your solicitor will disclose the Unilateral Undertaking during conveyancing. If you inform us ahead of sale, we simply update our records with new owner details.

Planning to extend your property in future? Discuss this during the survey. We can design system capacity to accommodate planned extensions, ensuring your upgraded system won’t limit future development.

If extensions arise after installation, contact us – many systems have spare capacity, or modifications may be possible.

There isn’t one. The economics are straightforward:

• Developers must purchase phosphate credits to gain planning approval in affected catchments – it’s a legal requirement, not optional
• Your upgraded system creates measurable, permanent phosphate reduction
• These reductions become credits – the credit value funds your upgrade plus WCI Nutrient Neutrality’s costs

You receive an upgraded system, including professional groundworks.

Developers gain planning approval.

Somerset’s rivers get cleaner. It’s an environmental partnership.

WCI has over 40 years of established presence in Somerset’s water and wastewater sector. We’re not a startup chasing a trend – we install, service and maintain thousands of systems across the region.

Our Managing Director, Brad Taylor, pioneered this entire upgrade credit model – an innovation now replicated nationwide. We originated this approach and have refined it through years of practical delivery.

We’re here for the long term. Even if nutrient neutrality regulations change, your upgraded system remains a superior, fully warranted installation that you own outright.

The performance difference is dramatic:

• Old septic tank: Typically discharges 1.5–2.5 kg phosphate annually
• New treatment plant: Discharges less than 0.1 kg phosphate annually (over 95% reduction)

We produce a Technical Mitigation Report (TMR) demonstrating the phosphate reduction for council approval – this proves the environmental benefit is real and measurable.

Beyond phosphates, modern treatment plants simply work better:

• More effective treatment of all pollutants
• Better handling of variable flows and loads
• More reliable operation with less maintenance
• Compliance with current environmental standards

If site-specific issues prevent installation (though this is uncommon), we’ll explain why and, where possible, suggest solutions.

Common issues and solutions:

Problem: Rainwater currently mixed with foul drainage
Solution: Divert rainwater to soakaway (you arrange this work, then we proceed)

Problem: Existing drainage has faults
Solution: Repair drainage (you arrange repairs, then we proceed)

Problem: Very unusual ground conditions or site constraints
Solution: We may offer alternative system design or, if genuinely impossible, explain why upgrade can’t proceed via the free scheme (though we may quote paid alternatives)

No obligation until you sign the Unilateral Undertaking. If you opt out before that point, there’s no financial charge.

Yes. You’re free to use any approved service contractor for annual inspections and maintenance.

WCI Service Engineers offer this service (we know the systems intimately, having installed them), but choice is yours. Many homeowners prefer the convenience of staying with WCI Group, but it’s never required.

Day 1: Installation team arrives, establishes site setup, delivers equipment
Days 2-4: Excavation, tank installation, pipework connections, electrical hookup
Day 5: Final connections, commissioning, testing, handover

During installation:

• We bring portable toilet facilities so you’re never without facilities
• We minimise disruption with controlled working areas
• We restore excavated areas to basic standard when complete

You don’t need to be home during installation (many homeowners continue working), though some prefer to observe progress.

Every system has emergency contact details displayed on the kiosk for urgent issues.

For routine questions or service scheduling, contact WCI Service Engineers: 01984 623 404

Your manufacturer warranty covers equipment defects (terms vary by manufacturer, typically 2+ years). Warranty remains valid as long as annual servicing is maintained – another reason regular maintenance matters.

If you decide not to proceed with an upgrade of your sewage treatment plant with WCI Nutrient Neutrality, or indeed, if your property is not eligible for a free upgrade as part of this scheme, rest assured that your details will not be shared with anyone outside of WCI Group.

In line with our company privacy policy, we hold all personal data securely and will not pass details of your property or its sewage treatment plant onto any third party.

Keep your existing septic tank functioning reliably:

WCI Service Engineers can provide:

• Routine servicing to prevent breakdowns
• Compliance surveys if required for property transactions
• Smell investigations if you’re experiencing odour issues
• Rectification work for aging systems needing repair

Or consider a paid upgrade if you prefer not to wait:
The free scheme waitlist currently exceeds 12 months in most areas due to council approval processes. If you’d rather upgrade immediately, WCI Project Engineers can quote a paid installation with no waitlist.

Contact our team to discuss options: 01984 623 404

The Free Upgrade scheme isn’t suitable for systems that need immediate attention.

The free upgrade scheme is entirely funded by developers purchasing nutrient credits. This funding is directly linked to local planning approvals. 

We’re still here to help. If your current septic system is failing, or you require an upgrade for property sale reasons, waiting indefinitely is not a safe or practical option. 

With over 40 years of experience, WCI Group is the trusted expert in off-mains drainage and we offer fast, guaranteed solutions.

Council tax: No direct impact. Your property classification doesn’t change simply because you have a better wastewater system.

Property value: Positive effect, if any. You’re selling a property with a modern, compliant, professionally installed wastewater system rather than an aging septic tank. Most buyers view this favourably, particularly in areas where septic tank replacement costs concern purchasers.