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Adoptable Sewer Pipe Explained

Explore MetroSewer, an adoptable twinwall polypropylene (PP) sewer pipe system designed to meet water authority standards - ideal for new, replacement, and adoptable sewer projects.

When installing a new sewer system, especially for developments that require adoption by local water authorities, it is crucial to choose products that meet the latest industry standards. In this guide, we explain what adoptable sewer pipes are, why they are necessary, and take a closer look at MetroSewer, a modern, compliant solution now available from Drainfast.

What is an Adoptable Sewer Pipe?

An adoptable sewer pipe is a drainage system that meets the specifications required by water companies to be taken over for long-term maintenance after construction. If a sewer is to be adopted, it must comply with national guidelines such as the Design and Construction Guidance (DCG) for England or Sewers for Scotland, ensuring the system is durable, efficient, and compatible with public sewer networks.

For a sewer to be adoptable, both the pipes and fittings must meet stringent standards on strength, durability, and jetting resistance to ensure long-term performance.

What is MetroSewer?

MetroSewer is a structured wall twinwall polypropylene (PP) sewer pipe system designed for use in adoptable and non-adoptable gravity sewer applications. Available in 150mm, 225mm, and 300mm diameters, MetroSewer is a versatile option suitable for new developments, replacement sewers, and infrastructure upgrades.

Manufactured to BS EN 13476-1 & 3 and WIS 4-35-01, MetroSewer holds the Kitemark certification (KM 800575), providing assurance that it meets all relevant performance criteria for sewer adoption.

Key Features of MetroSewer

Fully compliant with water industry specifications for adoptable sewers
High stiffness rating (SN8) for structural integrity and resistance to deformation under load
Meets WIS 4-35-01 for high-pressure jetting resistance
Made from twinwall polypropylene (PP) for excellent chemical resistance and long service life
Lightweight and easy to install compared to traditional concrete alternatives
Lower transport carbon emissions, making it a more sustainable option
Supplied in Terracotta Orange (RAL 8023) for easy identification as a sewer system
Full range of pipes, bends, junctions, reducers, adaptors, and accessories

How Does MetroSewer Compare to Other Systems?

MetroSewer is positioned as an alternative to other structured wall sewer pipe systems, including UltraRib, Ultra3, and Polysewer. It shares key similarities with these systems, including:

Designed for gravity-fed sewer systems
Manufactured to high stiffness and structural standards for underground installation
Fully compliant with water authority adoption requirements
Supplied in 3m lengths for easy handling and installation

One of MetroSewer’s key advantages is its compliance with both BS EN and WIS standards, ensuring long-term reliability for adoptable applications.

When Should You Use MetroSewer?

MetroSewer is ideal for:

New housing developments requiring water authority adoption
Infrastructure projects, including roads, commercial, and public works
Replacement of existing sewer networks where adoptable standards are needed
Private drainage systems needing high-quality, durable performance

MetroSewer is also an excellent alternative to concrete sewer pipes, offering a lightweight, fast, and safe installation process with lower transport carbon emissions.

Handling and Storage Considerations

Although MetroSewer is durable, proper handling and storage are important:

Store away from prolonged UV exposure if kept for more than three months
Use timber-framed packs for easy transport and site handling
Inspect pipes and fittings before installation to ensure they are in good condition

MetroSewer FAQs

What is an adoptable sewer?

An adoptable sewer is a drainage system that meets water authority standards and can be transferred to their ownership for long-term maintenance. These systems must comply with national regulations such as DCG (England) or Sewers for Scotland to ensure durability and efficiency.

How is an adoptable sewer pipe different from a non-adoptable one?

Adoptable sewer pipes must meet specific industry standards for strength, resistance, and longevity to be approved by water authorities. Non-adoptable pipes may still be high quality but are generally used for private drainage systems not maintained by water companies.

What type of pipe is used for residential sewer lines?

For adoptable sewer systems, MetroSewer twinwall PP pipes are a compliant option. However, for private residential sewer lines, a more cost-effective smooth-walled sewer pipe may be used instead.

How is a drainage pipe different from a sewer pipe?

Drainage pipes are typically smaller in diameter and used to transfer waste from one or a few properties. Sewer pipes are larger and designed to carry wastewater from multiple dwellings to a main sewage system.

What sizes of MetroSewer adoptable pipe are available?

MetroSewer is available in three diameters: 150mm, 225mm, and 300mm. A full range of junctions, bends, couplings, reducers, and adaptors is also available to create a complete adoptable sewer system.

For more guidance on sewer systems or to speak to an expert, contact our team today.

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