Sewage Treatment Plant Installers

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For sewage treatment plant installations and repairs Mantair Contracts Division provides homeowners with a complete design, installation and maintenance service.


Throughout many rural areas of the UK, many properties, both domestic and commercial are not connected to "mains drainage" for the disposal of sewage and waste water.  As leading independent installers of sewage treatment plants and septic tanks, Mantair is ideally placed to provide homeowners with a sewage treatment system to meet their budget and site requirements.

Whether you are seeking a small domestic installation of a packaged sewage treatment plant, septic tank, septic tank conversion unit or merely require advice over the telephone, Mantair has a track record of service, experience and quality that sets us apart from the rest. All projects are carried out in accordance with Environment Agency Regulations and Section H2 of Building Regulations. 

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Orford Ness


Featured Case Study 

Client - National Trust.

Location - Orford Ness, Orford, Woodbridge, Suffolk.

Orford Ness is a 10 mile shingle spit of land off the Suffolk coastline and is separated from the mainland by the River Ore.  Orford Ness is the largest vegetated shingle spit in Europe and is both a Site of Special Scientific Interest (SSSI) and is also a RAMSAR Site.

Top secret military testing was carried out at this designated Outstanding Area of Natural Beauty during both World Wars and Orford Ness was home Landscape Orfordto both the Ministry of Defence’s Experimental Flying Research Station, and after World War 2, the Atomic Weapons Research Establishment. 

Orford Ness is now owned by the National Trust and is open to the public for parts of the year.  Due to an ineffective septic tank soakaway system serving the wastewater facilities on the Ness, the National Trust asked Mantair Limited to investigate and provide a solution to the problem, taking into account the wide variation in wastewater flow between winter and summer months.

Prior to the design element of the project, Mantair carried out a full site investigation including a detailed land survey for unexploded ammunitions and underground services.  Following the various preliminary site surveys, Mantair liaised with the Environment Agency, English Nature and Suffolk Coastal District Council regarding the project to determine an acceptable wastewater treatment solution.

Taking into account that Orford Ness is an internationally important site for nature conservation, the Environment Agency and English Nature accepted Mantair’s wastewater treatment proposal which comprised two sewage treatment systems and a flow splitting chamber which allows the flow to be diverted to either of the two systems.  For low season during winter, a Mantair septic tank conversion system was fitted within the existing septic tank, converting the tank into a fully functioning sewage treatment plant.  In summer the Ness is open to the public and the wastewater flow increases substantially.  A 42PE packaged sewage treatment plant was installed to cater for the increase in flow during summer.

The Orford Ness project in Suffolk posed significant challenges to Mantair engineers as there is still dangerous debris buried on the Ness, including bombs, and the only access onto Orford Ness is from Aldeburgh along shingle beach on a Unimog vehicle, or from Orford Quay on a landing craft.  Timing was also crucial on the project as the water table on the Ness is affected by the tide and all excavations had to be carried out within a certain time frame.

Orford NessMantairMantairSewage Treatment Plant Installation

Despite the complexity of the Orford Ness project, the pre-planning and experience of the Mantair engineers ensured that the project was completed efficiently and without any problems.



mantairCase Study 2 - Berkshire

Mantair sewage treatment plant installation in Berkshire.  This sewage treatment plant was installed at a 3 bedroom property in Woodcote, nr. Reading, Berkshire. Click here




Airotec sewage treatment plantCase Study 3 - Cambridgeshire

Airotec sewage treatment plant installation in Cambridgeshire for the National Trust.  This sewage treatment plant was installed at a 3 bedroom property on the National Trust Wimpole Estate in Cambridgeshire. Click here




Tricel sewage treatment plantCase Study 4 - Essex

Tricel sewage treatment plant installation to serve a 4 bedroom house on the outskirts of Chelmsford in Essex.  This project included full installation and commissioning of the sewage treatment plant.  Click here




Peat sewage treatment plantCase Studies 5 & 6 - Norfolk

Puraflo Peat sewage treatment plant installation in Norfolk for the National Trust.  This sewage treatment plant was used to solve a septic tank problem at a property located on the National Trust Blickling Estate in North Norfolk.

Sewage treatment plant installation at Tower Windmill, Burnham Overy, Norfolk.  Click here 




Septic tank installation SuffolkCase Study 7 - Suffolk

Installation of a replacement septic tank at a domestic dwelling on the outskirts of Woodbridge in Suffolk.  Click here




Case Study 8 - Surrey

MantairSewage treatment plant installation to serve a small business park near Guildford, Surrey.  This project included full installation and commissioning of the sewage treatment plant.  Click here





How Mantair Can Help You!

mantair servicesMantair offers a comprehensive sewage treatment plant and septic tank service.  This includes free site inspections, guidance and advice on the most suitable system for the client's requirements, complete installation, commissioning and full after sales care. 

Mantair provides the following services:

  • Domestic sewage treatment plant installations;
  • Commercial sewage treatment plant installations;
  • Sewage treatment plant repairs;
  • Sewage treatment plant maintenance servicing;
  • Septic tank installations;
  • Septic tank conversion unit installations;
  • Septic tank soakaway installations;


British Water Codes of Practice for Small Wastewater Treatment Systems


Flows & Loads 3 Sizing Criteria            Installation Guide                       Users Guide

British WaterBritish Water   Installation Guide Click to view the full digital publication online

            Click here to Download PDF                            Click here to Download PDF                         Click here to Download PDF


For further information, click here or Freephone


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