Wick Drains have a rectangular cross section. The core is plastic so that it serves as a channel allowing water to flow freely. This core is surrounded by a thin filter casing made of a material that acts as a barrier to prevent the soil surrounding the drain from penetrating into the core, while at the same time allowing water in.
Wick Drains can be driven into the ground statically or dynamically. In some very soft soils, water jets with open pipe mouth or pipe drilling can be used.