Abstract: A storage tank (10) for storing a fluid, such as water, having a wall defined by a plurality of panels (12) which are retained by opposed side edges between adjacent support members (11). The support members have a base portion (13) and a support portion (15) and are free-standing on the base portion (13) on an earthen floor allowing the tank (10) to be constructed at sites without concrete foundations such as a concrete pad or ring. Preferably all that is required prior to construction of the tank (10) is for the site to be graded (if necessary). The tank also has a liner (20) that lines the interior surfaces of the wall and the floor.