HDPE geomembrane installation

  • Geomembrane installation

    Cofra  specialises in the fabrication and installation of geomembranes. Cofra is the largest installer of geomembrane in the Netherlands on waste disposal sites and in the civil application of the KIWA-certified 2.0 mm HDPE geomembranes. Cofra was also the first contracting company to be certified for the of plastic membrane in accordance with the KIWA BRL K537. For more than 25 years our installation teams have stood ready to perform any task according to strict quality standards for the installation of geomembranes.

  • Geomembrane installation A9


In HDPE geomambrane seals, an area is sealed off against air and liquid using a membrane. At waste disposal sites, HDPE membrane is used for the installation of both bottom and top seals. In civil applications, bottom ash from waste incineration plant and contaminated soil is sealed off using HDPE membrane. Cofra can install the membrane both horizontally and on gradients. For vertical seals please refer to the Geolock® brochure.

Why HDPE geomembrane?
HDPE geomembrane is resistant to a large number of chemicals, including acids, salts, alkalis, alcohol, oils and hydrocarbons that occur in practice. The HDPE to be installed by Cofra complies with the requirements summarised in the BRL-K 538/01 “Beoordelingsrichtlijn afdichtingsfolies van hoge dichtheid polyetheen (PE-HD) zonder versterking” (Assessment directive for sealing membranes made of high-density polyethylene without reinforcement). The HDPE is made of high-density polyethylene (HDPE) with a proportion of carbon black, anti-oxidants and stabilisers. This is the most commonly used membrane for the sealing of rubbish tips, dredging tips, lagoons and water

Installation of the HDPE geombembrane system
The membrane is unrolled with the aid of a “spreader”. This spreader is suspended from a hydrolic excavator. The membrane strips are laid with an overlap so that they can be welded together. Cofra uses two different welding methods. Automatic welding with a hot bolt or wedge welding machine or channel welding and manual welding with an extrusion welding machine. Automatic welding is used for making long weld seams between the membrane strips. Extrusion welding is used for seams that cannot be produced mechanically, such as details, repairs and lead-through constructions. All welding methods require a high level of expertise, both with regard to implementation and in terms of checking to guarantee optimal weld quality. Before the start of a job, both the competence of the technicians and the function and set-up of the welding machines are checked by doing test welds. These are checked daily in a mobile laboratory. The final checking of the welding comprises an inspection to determine the sealing of the weld. In the case of channel welds the welds are squeezed using air pressure. In the case of extrusion welds the welds are tested using a vacuum or flashing. Inspection is performed by an independent accredited inspection agency.


Applications of the HDPE geomembrane technique include:

  • Waste disposal sites, bottom sealing and final coverage
  • Waste incinerator embankments
  • Waterbasins
  • Soil protection



Advantages of Cofra as an HDPE geomembrane installer and mover:

  • High quality
  • 25 years’ experience
  • Long service life
  • Resistant against chemicals
  • Large installation capacity


Reference Cofra geomambrane installation

Reference geomembrane installation projects Area(m2) Projectsheet Video
Reconstructie A27 Almere, Netherlands 220.000
Eindafdichting Schinnen fase 3 Schinnen, Netherlands 100.000
Bovenafdichting Geitenwei Gouderak, Netherlands 10.500
Stortplaats Meersteeg Geldermalsen, Netherlands 127.000
Landfill De Lepelaar Muiderberg, Netherlands 17.500
Detour N381 Oosterwolde, Netherlands 44.000
Omlegging(detour) A9 Badhoevedorp Badhoevedorp, Netherlands 190.000
Stortplaats Wijster, Netherlands 63.000
Stortplaats Wijster, Netherlands 49.000
Terrein Van Schie, Netherlands 1.000
MET Terrein tank, Curacao 26.500
Stortplaats Zeeasterweg, Netherlands 90.000 Projectsheet
Stortplaats Wijster, Netherlands 56.000 Projectsheet
Vopak terminal Eemshaven Tankpits, Netherlands 28.500
Stortplaats Nauerna compartiment, Netherlands 23.000
Californie Bassin 14B-1 Venlo, Netherlands 9.500
Stortplaats Veendam, Netherlands 288.000
Stortplaats Wijster talud 3.1, Netherlands 58.000 Projectsheet
AVI terp N23 Swifterband, Netherlands 24.000
Bovenafdichting Zevenbergen, Netherlands 69.000
Vopak Eemshaven Tankpads, Netherlands 34.500 Projectsheet
2004-2010 – Volgermeerpolder, Netherlands 1.000.000 Video
Eurotank Amsterdam, Netherlands 3.545 Projectsheet
Bovenafdichting Zevenbergen, Netherlands 57.450
Stortplaats Gulbergen Nuenen, Netherlands 7.800
Stortplaats Crayestein Dordrecht, Netherlands 73.500
VAM Wijster talud 1Aa en 3.4, Netherlands 67.000
Stortplaats ArmhoedeLochem, Netherlands 45.000
A2 Verbreding Culemborg – Deil, Netherlands 14.000
Banscheiding Ilperveld Landsmeer, Netherlands 20.000
A2 Verbreding Culemborg – Deil, Netherlands 23.500
Stortplaats De Koornwaard, Netherlands 45.000
Stortplaats VAM Wijster Talud, Netherlands 60.000
Stortplaats Gulbergen Nuenen, Netherlands 85.000
Stortplaats Spinder Tilburg, Netherlands 90.000
Stortplaats Armhoede Lochem, Netherlands 60.000
Reconstructie N302 Harderwijk, Netherlands 40.000
Stortplaats Zevenbergen Moerdijk, Netherlands 60.000 Projectsheet
Stortplaats Montfort, Netherlands 141.000
Eindafdichting stort Schinnen, Netherlands 58.000
AEB Westpoort Terp 3 Amsterdam, Netherlands 36.600
Stortplaats Gulbergen, Netherlands 93.500
Budelco gipsbekken AWN 2 Budel, Netherlands 70.375
GP Groot Alkmaar, Netherlands 15.000
Afvalverwerking Vink B.V., Netherlands 12.900
AEB Westpoort Terp 1/ 2 Amsterdam, Netherlands 81.100
Kolendepot Electrabel Nijmegen, Netherlands 18.450
Stortplaats Gulbergen Nuenen, Netherlands 22.500
A&G Milieutechniek Europoort, cutting liner Video
Stortplaats Zeeland Nieuwdorp, Netherlands 30.300
Stortplaats Ullerberg Ermelo, Netherlands 157.000
A2 AVI Den Bosch-Rosmalen, Netherlands 49.500
VAM Wijster, Netherlands 81.100
Stortplaats Meerendonk Den Bosch, Netherlands 52.600
VAM Wijster, Netherlands 49.500
Spinder, Netherlands 11.000
Vink Barneveld, Netherlands 49.300
Terrein Slufter Rotterdam, Netherlands 76.050
Escravos, Nigeria 350.000



Design information geomembrane liner

Before the placement of a flat geomembrane liner construction, little or no geotechnical calculations are performed. However, when the liner is placed on a slope, stability calculations need to be performed to ensure the quality of the construction.

To be able to make a stability calculation, the friction properties of each of the layers within the construction should be known or investigated. The layer with the lowest friction properties is used in the stability calculation performed to review the safety factor between the opposing and the driving forces within the construction. In general a safety factor of 1.3 is used for the final situation. If the construction does not meet this safety factor, a geogrid or a different liner is designed or advised like a textured LDPE geomembrane liner.

Due to the functional demands of the construction the calculations are made without additional strength from strains in the liner or any material except the geogrid.

In the case you would like us to perform a design, the following information is required:


  • Cross section through the construction showing the maximal height and width of the slope
  • Total length of the slope together with the angle of the slope
  • Sketch indicating the area and location where the construction is required

Geotechnical data

  • Geotechnical parameters ( unit weights, frictional properties)
  • Construction sequence of the construction with geotextiles used including type indications and manufacturer
  • Frictional properties of the materials with each other.

In the case you have only a limited amount of data available for the design, you can always contact our geotechnical department in order to see if we can perform a design using the available data, or whether there is a need for additional site investigation. We also have the possibility to perform the tests determining the frictional properties of the materials used

Our other activities: