Woven geotextile is an effective drainage medium with a filtration function. This geotextile fabric prevents the clogging of drainage channels. Wrapping ungraded gravel with woven geotextile allows water to pass through and acts as a barrier to soil particles. With a wide range of pore sizes, it can be matched with differing soil types for optimum performance.
Geotextiles which have on drainage capability ie : woven or heat bonded nonwovens are unable to act as a drainage media at the soil/fill interface.