Abstract An experimental study on the sedimentation of a permeable floc was conducted using a polystyrene latex floc having a consistent structure composed of uniform spherical particles. The combined measurements of a) the settling velocity ( V f) of a single floc as a function of maximum distance between particles in the projected floc ( D max) and b) D max as a function of the number of primary particles ( i) were designed to evaluate the magnitude of permeability of a floc experienced during sedimentation. The measured values of log( V f) plotted against log( D max) indicated a linear relation over the entire range of measurements. The Debye-Brinkman equation as well as the proposed two-sphere collision model were applied to the analysis. The values of permeability obtained as a function of volume fraction defined in the ellipsoidal domain were found to be much higher, with values changing more rapidly than the value previously obtained for a swarm of spheres or fibres in a porous media which are considered to exhibit a homogeneous distribution of the solid throughout space.