Aquadrain 20H drainage composite is a two part prefabricated sheet drain consisting of a 3-dimensional polypropylene formed dimple core covered with a woven polypropylene filter fabric bonded to one-side. The filter fabric is bonded to each dimple to minimize fabric intrusion into the core resulting from backfill pressure. The polypropylene core resists chemical attack and degradation in soil. The formed dimple core provides compressive strength and collects water for flow to drainage discharge pipes. The filter fabric allows water or other liquids to pass into the drainage core while restricting the passage of soil particles.