Drainage Geocomposites

Drainage Geocomposites

Geocomposite Drains

Application Function

Drainage | Ground Stabilisation

Market Sectors

Highways | Landfill


1B, 1B1, 1BH1, 1BZ, 1C1 & 1E1

Terram Geo-composite drains are manufactured by bonding together textiles, membranes and nets in different combinations to create easier-to-install replacements for conventional granular layers. The textile provides the filter function so this allows liquids and gases to pass into the net core but prevents soil particles from washing into and clogging the core. The net collects the liquids and gases which can then be conveyed to collection points. Membranes are used to provide the barrier function and prevent the passage of liquids and the majority of gases.

A composite must: 

  • Be robust to survive installation and service life
  • Be stable under load to resist deformation that could ultimately restrict flow
  • Have good chemical resistance

It's filter must:

  • Possess an apparent pore size to suit the soil and prevent the ingress of fines
  • Provide sustained performance without blocking
Terram composite drains are proven to satisfy these criteria and stand the test of time. The products have established an impressive track record in building and construction projects across the world for over forty years.

The benefits of using Terram composite drains include:

  • High-volume flow paths for liquids and gases
  • Lightweight and easy to handle
  • Quick and easy to install
  • Cost-effective replacement for primary natural resources
  • Manufactured in the UK to high standards using state-of-the-art lines
  • Reduced environmental impact by avoiding the use of natural-occurring minerals
  • Lower haulage costs, lower material costs and lower installation costs

Typical applications for Terram Geo-composite drains:

  • Highways: vertical edge-of-carriageway drains intercept the lateral flow of ground water. Modern fin drains reduce excavation, reduce backfill quantities and reduce installation time. In-slope drainage increases geotechnical stability.
  • Retaining walls and bridge abutments: to reduce pore water pressure and avoid backfill saturation.
  • Engineered landfills: with the additional requirement of long-term chemical resistance and high compressive strength.
  • Tunnels: ground-water-seepage interception between rock face and the tunnel lining.
  • Buried structures: vertical and horizontal drains for basements, culverts, car parks, reservoirs, etc.
  • Roof gardens: Green roof systems require lightweight components capable of high in-plane water flow, good resistance to creep and high flow rates.

Roll Width (m)2.0/3.8*/4.02.0/3.8*/4.02.0/3.8*/4.02.0/3.8*/4.02.0/3.8*/4.0
Roll Length (m)25/50/10025/50/10025/50/10025/50/10025/50


TERRAM Roads & Highway Solutions
Standard Geocomposites
1BZ Data Sheet
Installing TERRAM geocomposite drains
BODPAVE 85 Porous car parking (SparkOne Bristol)
1B1 - Area drainage beneath artificial playing surface (Portsmouth)
1BZ - Drainage to the rear of a retaining wall (Carluke Park & Ride)