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Execution of underground infiltration systems

Underground infiltration crates


Perfect execution is certainly crucial in projects that are difficult to repair later, such as underground constructions. For this reason, from the very start of the execution certification process, it was decided to include the installation of underground infiltration systems as one of the test cases.


These underground infiltration systems are fairly new and not always sufficiently well known. Moreover, these systems come in all shapes and sizes:

  • infiltration crates assembled on site and wrapped in geotextile;
  • horizontally installed permeable pipes made of porous concrete or plastic;
  • infiltration system using concrete basements;
  • Porous and soilless concrete inspection chambers;
  • infiltration manholes in porous prefabricated concrete and concealed porous concrete gutters;
  • vertical infiltration piles and street gullies with vertical infiltration;
  • infiltration units made of prefabricated geotextile-lined infiltration crates;


There was a need for clear guidelines on how to construct a quality infiltration system. The representatives of the sector laid down the general requirements in PTV 8003. In addition, a partial PTV was drawn up for each different version. In addition, a pre-treatment system must always be provided.


In the course of 2021, the certification regulations will be further finalised so that this execution certification can then be started. In addition to the installation of the infiltration systems, their cleaning will also have to be certified. This certification is also being worked on at the moment.


Execution certification can be applied by a contractor or an executor of the relevant execution.

Applying for a certificate can be done digitally, via our website. Here you will find all the AFD forms with which the application can be done. Under ‘Team’ you also find the contact persons per product. They will be happy to help you further.