Geotextiles are permeable nonwoven fabrics used to separate, filter, reinforce, protect or drain. Geotextiles allow filtration or separation of granular layers in roads and rail applications, used to protect membranes in landfill applications, used in coastal defence applications and used in landscaping to protect surfaces and structures from weeds and root growth.

Geotextiles are availabel as woven and non-woven. As liner protection, against physical damage, the non wovens are normally the answer. They are made up of fibers of polyester or polypropylene in random directions and punched together by needles during the manufacturing process. Geotextiles are commenly used to separate layers like clay and drainage and to protect liner from damage.