Altering, relocating or installing a sewer connection isn’t a construction task that anyone can take on. It’s a highly regulated activity governed by strict legal, safety and engineering standards.

Whether you’re moving a sewer inspection point, installing a new connection for a home extension, or diverting a public sewer to make way for a new-build project, the process requires skilled planning, precise execution and formal approval from your local water authority. The work is heavily regulated, technically demanding, and legally controlled.

This is why using a qualified sewer connection specialist like Premier Drainage Solutions is essential. Our job is to provide a high-quality service while also ensuring legal compliance, protecting your property from drainage failures, and delivering work that meets the technical requirements of Anglian Water, Thames Water or Southern Water.

Why Sewer Connection Work Requires Accredited, Experienced Specialists

To help illustrate why sewer connection experts are essential, the following nine points break down the key regulatory, technical and legal factors that make sewer connection work far more complex than it may appear.

From statutory approvals and water-company engineering standards to deep-excavation safety and environmental compliance, each point highlights a critical area where certified sewer connection specialists ensure your project is completed safely, legally and to the required standard.

1. Legal Requirement for Section 106 Approval

Any new or altered connection to a public sewer requires written approval under Section 106 of the Water Industry Act 1991.

This applies whether you are:

• connecting a new property,
• relocating an existing connection,
• moving or installing a manhole,
• adding additional flows (e.g., converting one property into several), or
• altering drainage layouts.

Water companies will refuse approval unless the design, drawings, method statements, materials, and technical approach all meet their strict standards. Sewer connection experts understand these requirements and will assist in preparing compliant documentation.

2. Compliance with Water Company Engineering Standards

Each water company – Anglian Water, Thames Water, Southern Water, and beyond – has its own engineering specifications covering:

• connection method
• pipe gradients and sizes
• approved materials
• depth requirements
• manhole design
• surface/foul water separation
• backfill and compaction
• access and inspection requirements

A sewer connection specialist can work with your project to ensure your design complies with the exact requirements of the water authority in your region, reducing the risk of rejection, delays or expensive redesigns.

3. Safe Deep Excavation Standards

Public sewers are often several metres below ground. In older or urban areas (especially London, Essex, Cambridgeshire and Kent), depths of 4-6 metres are common, and some projects require excavations of 10+ metres. At Premier Drainage Solutions, we have experience digging down as far as 20 metres – which requires highly specialist equipment and knowledge.

This also triggers strict safety requirements:

• trench shoring and trench boxes
• safe entry procedures
• working near live utilities
• ground stability management
• confined space regulations

Only trained and competent sewer connection specialists – with experience excavating to significant depths – can legally and safely carry out this work.

4. Requirement for Method Statements and Risk Assessments

Water companies routinely demand site-specific documentation, including:

• detailed method statements,
• risk assessments (RAMS),
• excavation and shoring plans,
• traffic management plans (especially for highway works).

Specialist contractors like Premier Drainage Solutions will prepare these documents in a form that water companies and local authorities will accept.

5. Working on or Near a Public Highway

If the sewer connection or diversion requires digging in a road or pavement, you must comply with:

• New Roads and Street Works Act (NRSWA),
• permits from local highways authorities,
• traffic management plans,
• reinstatement standards (often the “Specification for the Reinstatement of Openings in Highways”).

Only NRSWA-accredited operatives are legally allowed to carry out such work.

6. Build-Over and Sewer Diversion Regulations

If a public sewer runs through your building footprint – which is extremely common in London, Kent, Hertfordshire, and Essex – you may need either:

• a build-over agreement, or
• a full sewer diversion, sometimes requiring design approval, CCTV surveys, or monitoring.

These processes require technical submissions and must be carried out by qualified specialists.

7. Mandatory Inspections & Certification

Thames Water, Anglian Water and Southern Water all require:

• inspection of the connection before backfilling,
• photographic evidence,
• as-built drawings,
• a final completion certificate.

If a non-approved contractor carries out works and backfills prematurely, you may be required to re-excavate at your own cost or submit expensive CCTV surveys to prove compliance.

8. Environmental & Flood Risk Regulations

Sewerage networks must protect against:

• groundwater contamination,
• pollution incidents,
• flooding or surcharge,
• misconnected surface water drains.

A specialist ensures foul water and surface water remain correctly separated and that the connection does not overload the local network – an increasing issue in rapidly developing regions such as Cambridgeshire, Kent and outer London.

9. Liability & Warranty Requirements

Water companies require that any works affecting public sewer infrastructure be carried out by competent and insured contractors (often with £5–£10m public liability insurance).

Improper work can cause:

• sewer collapse,
• flooding of neighbouring homes,
• environmental contamination.

Specialists carry the appropriate insurance and warranties, protecting you from financial and legal consequences.

Get in Touch with Premier Drainage Solutions

If you’re planning a sewer connection, diversion or inspection point relocation, we are ready to help. With 40+ years of industry experience, we offer a free initial site visit across London, Essex, Norfolk, Suffolk, Cambridgeshire and Kent, followed by clear and detailed quotations tailored to your project.

Our team provides full compliance and paperwork support, and as an ISO 9001:2015 certified contractor with proven experience excavating down to depths of 20 metres, we deliver safe, efficient and fully approved solutions every time. We pride ourselves on extraordinary customer service, supporting you from project design and planning through to final inspection and sign-off.

Contact Premier Drainage Solutions today to discuss your requirements and book your free site visit.