7500 to 15 000 psi the strands 14 of such geonets 12 may be caused to fold over flat in 10 000 hours or less such rollover will of course cause the two groups of strands 14 to present a height which is substantially less than the combined long dimension of two sets of strands and thereby significantly and undesirably reducing the transmissivity flow capacity provided by such prior art geocomposite 10 testing has also shown that at higher loadings such as 30 000 psi transmissivity for geonets according to the present invention is higher than it is for prior art geonets of fig1 3 having comparable material usages i e transmissivity per mass per unit area is greater with the geonets of the present invention a geocomposite 50 incorporating the geonet 30 of the present invention is shown in fig6 in the illustrated geocomposite 50 geotextiles 54 56 such as e g nonwoven needlepunched geotextiles spun bonded or heat laminated textiles as are known in the art are suitably secured to both sides of the geonet 30 such as by heat laminating fig7 illustrates in cross section a landfill 70 in which geocomposites 50 according to the present invention may be advantageously used as the landfill is made a first layer of geocomposites 50 a is laid down on the surface of the area on which the landfill 70 is being formed of course the area being covered may be extremely large and therefore more than one section of geocomposite 50 a will typically be required to cover the entire area at each layer fill 74 a will then be placed on top of the geocomposite 50 a to a desired depth.