Design of the reservoir lined with geomembrane data: slope (z) greater height of the water (h) free edge (bl) inlet flow (qe) ø discharge pipe cross slope to the bottom width of the anchor edge length of the underground anchor time of reservoir sizing and lime. hydraulic: net design volume bottom length (l) bottom width (a) area of the bottom (b) area of the water mirror (b) lowest height of the water (h-) reduction volume x slope (vp) net volume calculated total volume (with free edge) reservoir time (in h and min) minimum discharge time maximum discharge flow geomembrane area: slope length slope area anchorage area net geomembrane area