Groundwater drainage

During the construction of a water ponds, flows of underground water and water tables can be intercepted, wich must be drained to eliminate the hydrostatic pressure and guarantee the stability of the structure.

The fitting of INTERMAS geocomposites below the waterproofing allows:

  • Interception of underground flows.
  • Lowering the water table.
  • Cutting capillary ascents in clayey and loamy soils.

As INTERMAS geocomposites protects the geomembrane, it is not necessary to fit heavy protection geotextiles.

Gas venting

When designing and building a water ponds, it is advisable to analyse the presence of biogas in the subsoil (decomposition of organic material). The perfect impermeability of HDPE geomembranes is an impenetrable barrier to the gas on its route upwards. It accumulates below the geomembrane and exercises continuouspressure on the plastic. Pockets of biogas form, breaking the membrane and destabilizing the water ponds.

INTERMAS geocomposites fitted bellow the geomembrane is the solution.

  • It intercepts the ascent of gas.
  • It quickly conducts it to the grooved drain pipes (which direct it away from the area occupied by the basin)
  • It eliminates the pressure due to trapped gas.
  • It prevents the formation of dangerous pockets of biogas.

Leak detection

In water ponds storing pollution liquids (leachates, waste water, etc.) it is a good idea to install safety waterproof layyers and leak-detection drainage systems covering the whole surface of the water ponds to prevent the prelocation of substances that pollute the evironment.

So,INTERMAS geocomposites constitutes the most effective and economical method, thanks to its great drainage capacity under high loads an minimum slopes.

Why is INTERMAS drainage the ideal geocomposite for water ponds?

TECHDRAIN’S great drainage capacity on minimum slopes and under heavy loads makes it the ideal system for draining water leaks, gases and ground water at the bottom of the water ponds
INTERDRAIN is made of a geonet with one or two heat-set geotextiles, offering protective properties to the geomembrane, so it is not necessary to fit a geotextile. It is the most economical solution for drainage in water ponds.
Traditionally, geotextiles are normally used as a drainage system under water ponds. However, geotextiles do not have enough drainage capacity, so it is not a technically appropriate solution. Instead, INTERDRAIN and TECHDRAIN can offer the desired drainage solution.

INTERDRAIN Water ponds


Geocomposite drains are installed under the containment liner to avoid fluid pressure buildup and as a leak detection layer to create a void space through which leaking fluids can be detected and displaced outwards Formed by a biplanar HDPE geonet thermally bonded over one or both sides to nonwoven PP geotextiles


-Improves the drainage capacity or completely replaces the natural drainage layer -Homogeneous drainage solution that follows strict quality control procedures -Simple and aesthetic design that harmonically complements other geosynthetic systems -Lightweight and flexible composition -Highly robust and resilient, able to withstand the loads applied during installation -Chemically inert and imperishable -Fast, easy and reliable installation, does not require heavy machinery or qualified staff -Outstanding transportation capacity -Easy to store and protected against external agents -Low carbon footprint


-High transmissivity -Low core compressibility -Stable transmissivity over the long term in accordance with GRI GC13 Specification -Suitable for installation over steep slopes -Customizable geotextiles -Under ISO and ASTM Standards -In accordance with GRI GN4 Specification -Rolls up to 4-m wide and customizable length


Do you have a project in geosynthetic?

We encourage you to discuss your specific needs with our technical sales team which will be pleased to help you find the optimal solution to your needs.

Our catalog for Geosynthetic

Our catalog for Geosynthetic