Answer: Large, permeable fabric tubes filled with sand or dredged material
Notes: Scientists recently studied the offshore breakwater system using geotube technology along the Poonthura coast in Kerala. The study showed that the system led to major positive changes in the coastal landscape behind the breakwater stretch. Geotubes are large, strong fabric tubes filled with sand or dredged material. They are made from high-strength, permeable geotextile, usually polypropylene, which lets water escape while keeping solid particles inside. These tubes are used to build seawalls and barriers that protect coastlines from erosion caused by waves. Geotubes help reduce wave impact and retain sand on beaches, canals, and bays. They can be designed in different sizes and shapes for specific locations.
