SEWAGE ADOPTION REPORTS
 

What Is a Sewer Adoption Report

​

A sewer adoption report is a technical inspection and compliance assessment of newly installed drainage infrastructure that is intended to be adopted by a water company under a Section 104 agreement.

​

When a developer installs new sewers on a housing estate, commercial development or infrastructure project, those assets are often designed to become the responsibility of the local water authority. Before adoption, the system must be inspected to confirm that it:

​

    •    Has been installed to approved drawings
   •    Meets Sewerage Sector Guidance standards
   •    Is free from structural defects
   •    Is watertight and operational

 

The adoption report provides the documented evidence required for submission and review.

 

What Does “Adopted” Mean in Drainage Infrastructure

​

When a sewer is adopted:

    •    Responsibility transfers to the water authority
   •    Future maintenance becomes their obligation
   •    The developer is released from long term liability

​

If a drainage system is not adopted, it remains private. This means ongoing repair and maintenance costs may remain with a management company, landowner or developer.

​

Ensuring adoption is therefore both a regulatory and financial priority.

 

How Does a Section 104 Sewer Adoption Agreement Work

​

Section 104 of the Water Industry Act 1991 sets out the legal framework for sewer adoption.

Under this agreement:

​

    1.    Drainage is constructed to an approved design
   2.    Inspections and testing are carried out
   3.    Any defects are rectified
   4.    The system enters a maintenance period, typically 12 months
   5.    Final adoption is confirmed after successful review

 

Failure to meet inspection standards can result in rejection, delay and costly remedial works.

 

What Is Included in a Sewer Adoption Survey

​

A professional adoption inspection involves several critical stages.
Pre Adoption CCTV Drainage Survey
A full CCTV drainage survey is carried out to assess:

​

    •    Pipe alignment
   •    Joint integrity
   •    Cracks or fractures
   •    Displacement or deformation
   •    Standing water indicating incorrect gradients
   •    Debris or installation defects

​

High resolution footage is recorded and reviewed in accordance with recognised reporting standards.

 

Manhole and Chamber Inspections

​

Manholes and access chambers are inspected for:

​

    •    Correct benching
   •    Channel alignment
   •    Step irons and access safety
   •    Structural integrity
   •    Cover levels and positioning

 

Air and Water Testing

​

Testing confirms that the pipework is watertight and free from leakage or infiltration.

 

As Built Documentation

 

Accurate as built drawings and installation details must match approved designs. Discrepancies can delay adoption approval.

 

Common Defects That Prevent Sewer Adoption

​

Many drainage systems fail initial inspection due to avoidable defects.

Typical issues include:

​

    •    Incorrect pipe gradients
   •    Pipe sagging resulting in standing water
   •    Cracked or displaced pipe sections
   •    Poor jointing
   •    Debris left within pipework
   •    Damaged manhole benching
   •    Incorrect materials or installation methods

 

Identifying these issues early reduces project risk and prevents costly delays.

 

Sewer Adoption Defect Rectification and Compliance Support

​

At Arch Services, we do more than identify defects. As part of our civil engineering capability, we provide defect rectification works where required.

​

This may include:

​

    •    Excavation and replacement of defective pipe sections
   •    Re bedding and regrading to correct falls
   •    Joint resealing
   •    Manhole reconstruction
   •    Debris removal via high pressure jetting
   •    Targeted structural drainage repairs

​

Once rectified, the system can be re inspected and prepared for successful submission.

​

This integrated approach reduces the need for multiple contractors and helps developers maintain programme timelines.

 

How To Prepare Drainage Systems For Water Authority Adoption

 

To reduce the risk of rejection, developers should:

​

    •    Engage professional CCTV inspection before formal submission
   •    Ensure all debris is removed from the system
   •    Verify gradients and flow performance
   •    Confirm documentation accuracy
   •    Address minor defects before they escalate

​

Early compliance checks prevent last minute complications at the handover stage.

​

 

Why Professional CCTV Inspection Is Critical Before Handover

 

CCTV drainage surveys are central to sewer adoption reporting. Without detailed internal inspection, hidden defects may go undetected until reviewed by the water authority.

 

A professional survey provides:

​

    •    Clear visual evidence
   •    Structured reporting
   •    Defect coding
   •    Compliance insight
   •    Actionable recommendations

 

This allows corrective works to be carried out proactively, rather than reactively after rejection.

 

Supporting Developments Across South Wales, The South West and The West Midlands

​

Arch Services supports developers, civil engineering contractors and infrastructure projects across:

​

• South Wales including Cardiff and Newport

• The South West including Bristol and surrounding areas

• The West Midlands including Birmingham and regional development zones

 

Our team understands regional requirements and works closely with project stakeholders to ensure drainage systems meet adoption standards efficiently.

​
Frequently Asked Questions

 

What Is A Sewer Adoption Report?

​

A sewer adoption report is a technical inspection document confirming that newly installed drainage infrastructure meets required standards for handover to a water authority.

​​

What Is Included In A Section 104 Drainage Survey?

​​

It typically includes a CCTV inspection, manhole assessment, testing results and documentation confirming compliance with Sewerage Sector Guidance.

​

What Defects Prevent Sewer Adoption?

​​

Common issues include cracked pipes, incorrect gradients, standing water, joint failures and debris within the system.

​​

Who Is Responsible For Adoptable Sewers Before Handover?

​​

The developer remains responsible until final adoption is confirmed following the maintenance period.

​

How Long Is The Sewer Adoption Maintenance Period?

​

The maintenance period is typically 12 months, during which any defects must be rectified before final sign off.

​

Speak To Our Civil Engineering Team

​

Sewer adoption is a critical stage in any development project. Delays caused by non compliant drainage systems can impact handover, occupancy and project timelines.

​

Contact Arch Services Today

​

Arch Services provides professional sewer adoption reporting, Section 104 drainage surveys and defect rectification support to help ensure a smooth and compliant transition. If you are approaching handover or require a pre adoption inspection, contact our civil engineering team today to discuss your project requirements. Call our experts today on 0800 707 6771.