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Section 104 Sewer Adoption & Drainage Solutions
Specialist Section 104 adoption for developers and main contractors stuck in the 97% failure rate
Here’s the problem: only 3% of new sewers are actually getting adopted.
That means 30,000 homes can’t complete. £900 million in Section 106 contributions just… stuck. And developers holding liability for private maintenance that was supposed to be public. Residents discovering they’ll be paying £5,000-£20,000 every year for sewers that should’ve been free.
You need adoption certainty, not another 18-month process that'll probably fail anyway
You can’t sell homes or release retention until those sewers vest. Every month, waiting is capital sitting idle whilst water companies take their time with 2-4 design resubmission cycles, and inspectors keep finding defects you didn’t even know existed.
We handle this across the South West (South West Water territory), South Wales (Welsh Water), and Thames Valley (Thames Water). From that initial application through to the final vesting declaration. One partner managing the whole Section 104 journey.
What we can deliver for your site...
Why Section 104 adoptions fail and why it wrecks development programmes
The technical barriers water companies use to reject applications
There's an adoption management system that actually works...
Sewers adopted faster with fixed-fee certainty. One partner handling the entire process
Fixed-fee adoption management:
You know your costs upfront - applications, technical vetting, resubmissions, defect resolution, maintenance period management. No open-ended consultant fees that just keep growing.
Regional water company expertise:
We know South West Water, Welsh Water, Thames Water requirements intimately. Which inspectors want what. Which policies changed when. Who to call when things get stuck.
Applications approved first time (mostly):
DCG-compliant designs, complete hydraulic modelling, accurate as-builts, comprehensive SuDS documentation. Minimal resubmission cycles because we know what they're looking for.
Defect backlogs resolved fast:
CCTV surveys finding structural issues, repair programmes fixing non-compliance, documentation corrected. Getting existing schemes unstuck and moving toward vesting.
Bond waivers secured where eligible:
Severn Trent and others now offer bond waiver schemes. We navigate the eligibility criteria, potentially freeing up £50,000-£250,000 on major schemes.
Residents protected from private fees:
Public adoption guaranteed, not private maintenance contracts dumped on homeowners. Your scheme value protected, residents get free water company maintenance forever.
Why developers and main contractors choose Highways Plus
You’re managing completion deadlines and exit strategies. You need sewers adopted so schemes complete, capital gets released, and residents don’t inherit permanent maintenance liabilities they never signed up for.
What sets us apart
We're adoption specialists, not generalists:
Section 38, Section 278, Section 104 adoption management is what we do. Twenty-five years navigating highway and sewer vesting. We’ve seen every nightmare scenario.
Regional water company knowledge:
South West Water, Welsh Water, Thames Water requirements mastered. We know their inspection protocols, which policies changed in April 2020, how their checking fees actually work.
Fixed-fee certainty versus open-ended consultants:
You know your costs upfront. Resubmissions, defect resolution, maintenance period management – all included. No hourly billing that just keeps climbing.
Backlog schemes unstuck:
Got defects blocking adoption for 18 months? Design rejected three times already? We specialise in fixing stalled schemes and getting them across the finish line. It’s salvageable.
Integrated Section 38 and Section 104 management:
Roads and sewers adopted together. Traffic management coordinated, utility interfaces managed, single accountability from enabling works through to final vesting. One partner, one invoice.
Bond reduction strategies:
- We secure waivers where eligible, arrange sureties reducing cash requirements, accelerate vesting timelines releasing bonds faster. Your capital working for you, not sitting in escrow.
A clear, structured process that gets sewers adopted
Section 104 adoption needs methodical technical preparation, water company negotiation expertise, defect management capability. Full documentation at every stage. Transparent timelines throughout.
What you get...
Most schemes run through phased delivery. Technical application and approval first (4-8 weeks, assuming the water company’s responding). Legal agreement execution next (2-6 weeks). Then construction inspection and maintenance period management (12-30 months depending on scheme size and how cooperative the inspectors are feeling).
Typical timelines: 18-24 months for straightforward gravity systems with proactive management. 24-36 months for complex pumping station schemes. 6-12 months for backlog defect resolution on schemes already constructed (assuming defects aren’t catastrophic).
Technical assessment and application preparation:
Desktop review of your designs, DCG compliance checking, hydraulic modelling verification, as-built quality assessment. We assemble the complete application package - layout plans, long-sections, health and safety files, SuDS documentation. Everything they'll ask for anyway.
Water company submission and vetting management:
Application submission with supporting docs, checking fee coordination (yes, they charge you for checking your work), technical query response, design amendment cycles. We handle those 2-4 resubmission iterations water companies now seem to require as standard, securing technical approval.
Legal agreement and bond arrangement:
Section 104 agreement negotiation, legal fee management, performance bond setup or waiver applications. Getting that signed agreement in place before construction starts, protecting your position legally.
Construction inspection and compliance:
Pre-start notifications (10 working days minimum), scheduled site inspection coordination, defect identification and rectification management, as-built drawing updates. Keeping inspectors satisfied, construction on track, no nasty surprises.
Maintenance period management and vesting:
Provisional certificate secured, 12-24 month maintenance period supported, quarterly inspection coordination, final CCTV and structural surveys, vesting declaration achieved. Responsibility transferred to water company. Permanently.
Section 104 sewer adoption CASE STUDY
78-unit residential development, Somerset
The Challenge:
- Developer with a 78-home scheme nearing completion. Sewers had been installed 14 months prior but Section 104 application rejected twice by South West Water.
- Design non-compliance identified - inadequate hydraulic modelling, as-built drawings showing 15% variance from approved plans, pumping station telemetry not meeting specification. South West Water demanding full resubmission with updated calculations. Again.
- Scheme couldn't complete until sewers adopted. £2.1 million in completed homes just sitting there unsellable. £180,000 in holding costs accumulating. Residents due to exchange but solicitors flagging private maintenance liability (because of course they were).
Our Solution:
- Complete technical remediation starting with CCTV surveys and as-built verification. Found structural defects in three manholes - pipe deformation over 5% - plus two lateral connections installed incorrectly.
- Structural repairs completed in two weeks under traffic management. As-built drawings corrected with surveyed coordinates. Hydraulic modelling updated with actual pipe sizes and gradients (not what the drawings said). Pumping station telemetry upgraded to South West Water specification.
- Resubmission package assembled with comprehensive documentation. Technical approval secured in six weeks. First-time approval on third overall submission (which frankly counts as a win given the track record). Legal agreement executed, bond arranged, provisional certificate issued.
- Maintenance period managed with quarterly inspections, emergency repair protocol established, final vesting surveys completed. Vesting declaration achieved 16 months post-provisional certificate.
The Outcome:
- Adoption completed in 22 months total versus 36-month typical timescale
- Scheme completed, £2.1 million in sales released, holding costs stopped
- Residents protected from private maintenance fees (would've been £12,000-£18,000 annually for a scheme this size)
- Developer exit strategy achieved on revised timeline, capital released for next project
Proven delivery of Section 104 adoption across diverse sectors
Whether you’re developing residential schemes, managing mixed-use projects, or delivering housing association developments, you need sewers adopted so schemes complete and residents avoid permanent maintenance liabilities.
Sectors that rely on us:
Private residential developers:
Housebuilders managing Section 104 adoptions across single-phase and multi-phase schemes. Backlog defect resolution, maintenance period management, vesting acceleration. Protecting scheme value and resident interests.
Housing associations:
Affordable housing providers needing adoption certainty for new developments and remediation of backlog schemes. Fixed-fee management keeping budgets controlled, residents protected from private maintenance fees they can’t afford.
Main contractors:
Construction firms coordinating Section 104 alongside main works delivery. Application preparation, inspection scheduling, defect rectification, adoption interfaces with Section 38 road agreements managed seamlessly.
Commercial developers:
Mixed-use and commercial schemes requiring sewerage adoption as part of infrastructure delivery. SuDS integration, pumping station approvals, water company negotiations handled alongside broader adoption requirements.
Regeneration projects:
Brownfield and urban regeneration requiring complex drainage solutions and Section 104 compliance. Contamination interfaces, existing infrastructure conflicts, phased delivery coordination all managed.
Infrastructure delivery:
Public sector and strategic infrastructure requiring sewerage provision and adoption. DCG compliance, public procurement standards, comprehensive documentation meeting authority requirements.
Your Section 104 sewer adoption questions, answered...
How long does Section 104 adoption typically take?
18-24 months for straightforward gravity systems with proactive management. 24-36 months for complex schemes with pumping stations (they add 3-6 months minimum). Backlog defect resolution varies – 6-12 months depending on how bad the defects are. We provide detailed timelines based on your specific scheme and which water company you’re dealing with.
What's included in your fixed-fee adoption management?
Technical application preparation, DCG compliance checking, hydraulic modelling verification, water company submission and liaison, resubmission management (typically 2-4 cycles because that’s what they do now), legal agreement coordination, bond arrangement or waiver applications, construction inspection support, maintenance period management, final vesting coordination. Excludes only structural repairs to actual defects and water company statutory fees (application, checking, legal – they charge for everything).
What if my application's already been rejected twice?
Common scenario – 97% of applications face rejection at some point. We specialise in remediating rejected schemes. CCTV surveys identify structural issues, as-builts get corrected, hydraulic modelling updated, documentation completed properly. Most rejected schemes are adoptable with specialist input. Just needs methodical technical remediation and someone who knows what the water company’s actually looking for.
Can you handle pumping station adoptions?
Yes. Pumping stations add 3-6 months to timescales and require telemetry installation, specification compliance, rising main approvals. We manage the additional complexity – equipment specifications, remote monitoring setup, water company technical approval, extended inspection protocols. They’re more involved than gravity systems but perfectly manageable.
What's the 10% bond and can it be waived?
Performance bond, typically 10% of estimated construction costs (15% for pumping stations with some water companies). Held until final vesting as security you’ll complete everything properly. Some water companies now offer bond waiver schemes for developers with strong credit profiles – Severn Trent from January 2025, others likely following. We navigate eligibility criteria, secure waivers where possible, arrange sureties reducing cash requirements when waivers aren’t available.
What happens if defects are found during maintenance period?
You remain responsible for all repairs during that 12-24 month maintenance period. Water company inspects quarterly, identifies defects, you rectify at your cost within agreed timescales. If you don’t, they can engage contractors and recharge you. Common defects: structural damage, pipe deformation over 5%, inadequate documentation. We coordinate repairs, manage inspector relationships, keep maintenance period on track toward final vesting.
Why are only 3% of new sewers getting adopted?
Multiple factors. Inconsistent water company policies across regions. Rigorous DCG technical assessment with those 2-4 design resubmission cycles now typical. SuDS adoption uncertainty – some water companies adopt them, others just refuse. Timeline misalignment between water company approval processes and development programmes. Result: developers opting for private maintenance arrangements because adoption feels impossible, leaving residents with permanent fees.
Can SuDS features be adopted under Section 104?
Technically yes, but there’s massive regional variation. Some water companies actively adopt SuDS (South West Water and Welsh Water are generally supportive). Others resist or refuse outright. Requires comprehensive design statements, maintenance planning, long-term funding arrangements. We negotiate with your specific water company early, establish SuDS adoption eligibility before you design around it, provide alternatives if adoption’s not viable in your area.
Do you work with specific water companies?
Yes. Deep expertise with South West Water, Welsh Water, Thames Water – our target regional operators. We know their inspection protocols, which policies changed in April 2020 when DCG replaced Sewers for Adoption 6th Edition, how their checking fees work, which inspectors want what documentation. That regional knowledge accelerates approvals because we’re not learning their requirements on your project.
Got sewers blocking your scheme completion?
Book a Free, No-Obligation Section 104 sewer adoption Assessment
We’ll review your Section 104 status, assess adoption barriers, identify defects or documentation gaps, provide a written report with fixed-fee adoption management quotation and realistic timelines (not optimistic guesses).
No obligation, no sales pressure. Just expert advice from adoption specialists who’ve managed hundreds of Section 104 schemes across South West Water, Welsh Water, and Thames Water territories.
Call or fill out our form and we'll be in touch within 24 hours.
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