Ko te Whatunga Waihanga Waihanga ( Geocomposite Drainage Liners ) he momo mea hou mo te whakamaoritanga wai, i hangaia hei whakakii, hei whakakapi ranei i te onepu, te kohatu me te kirikiri. Kei roto i te HDPE geonet wera-hononga ki tetahi taha, ki nga taha e rua ranei o te geotextile werohia te ngira kore-whatu. E rua nga hanganga o te geonet. Ko tetahi hanganga he hanganga bi-axial me tetahi atu he hanganga tri-axial.