 Employing a solid cover or grating that is flush with the adjoining surface, this drain is commonly made of concrete in-situ and may utilize polymer- or metal-based liners or a channel former to aid in channel crafting and slope formation.Characterized by its long length and narrow width, the cross-section of the drain is a function of the maximum flow volume anticipated from the surrounding surface.Channels can range from to 2 feet in width, with depths that can reach .