Underdrain (Drainage Geotextile)

A geotextile is commonly used in subsurface drainage (underdrain) applications. A drain constructed along the edge of a road consisting of a gravel-filled trench wrapped with a drainage geotextile is one example. Other examples include prefabricated geocomposite edge drains by American Wick Drain (AWD), also known as drainboard or dimpleboard and a perforated pipe wrapped with a drainage geotextile sock.

In these systems, the drainage geotextile acts as a filter, allowing the water to pass, while restricting soil fines from entering into, and clogging, the sand, gravel or pipe portion of the drain system.

Woven Slit-Films Not Allowed

Most government agencies and state Department of Transportations have a specification for drainage geotextiles for use as underdrains. In almost all cases, a woven "slit-film" geotextile is not allowed, nor is it recommend for this application.

US Fabrics has a complete line of woven and nonwoven drainage geotextiles. Please refer to the links on the right for US Fabrics products that meet these specifications and to visit the composite drains, lightweight nonwoven and woven filtration product sections of our website.