Our dam liners are 0.5mm, 0.8mm, and 1mm thick. They are in widths to fit the size and shape of the excavated space. Faina innovations technical team will install it together with the client then test the liner over the next days or weeks. The best dam liner to use depends on the volume of water held and the surface type. If it is a large reservoir, a thicker liner is better. If the surface is smooth then a lighter gauge liner will work.