ChannelsGroundwater drainage under channels

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.

Our products


INTERDRAIN geonet and geocomposite drains offer a full range of solutions suitable in most common applications.


TECHDRAIN geonet and geocomposite drains have been designed to achieve outstanding transmissivity requirements under very high compressive loads.


Designed to ease the growth of vegetation and avoid the erosion in slopes and channels.

Volumetrical mat made of two nets assembled together for base support and shape configuration. On of them is a BOP net (Bioriented)


Designed to ease the growth of vegetation and avoid the erosion in slopes and channels. The intermediate reinforcement geogrid adds the required tensile resistance.

Constituted of an erosion control mat and a reinforcement grid

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