Flexible drainage pipe is a new type of piping material featuring reverse-filtered seepage, overcoming many drawbacks of other drainage pipes. Due to its unique design principles and the excellent performance of its constituent materials, it boasts strong drainage and渗水 capabilities. It harnesses both the "capillary" effect and "siphon" principle, integrating water absorption, permeability, and drainage into one seamless process. It is capable of meeting engineering design requirements with its pressure resistance, permeability, and anti-backflow function.