This paper is an extension to a previous theoretical model developed for non-segregating thickened tailings beach slope prediction. The original model was presented by two of the authors at Paste 2007 (Pirouz and Williams, 2007). The visual observations and experimental data from tilting flume testing at three different mine sites have been analysed and the findings are used to modify the theoretical model to be applicable to a wide range of slurries with different rheological and flow conditions. The overall structure of the new model is similar to the originally developed model and is based on the theory that, on a large scale, the slope of the overall tailings beach is determined by the slope of self-formed tailings channels. A modified Hedstrom Number (He) for tailings slurries’ flow has been introduced in this paper for the first time. The experimental data from flow-through tilting flume tests show that a strong correlation between the Reynolds Number (Re) and the Hedstrom Number exist for the flow condition at the equilibrium slope. This unique relation between the two dimensionless numbers defines the condition of flow in the self-formed channel and can be used to define the minimum required velocity (or minimum Reynolds number) required to achieve the total transport condition in channel flow. A modified model for the shape of the self-formed channel based on the stability of individual particles on the bank of the channel has also been presented. The validity of the available friction factor for calculation of head loss in non-Newtonian fluid has been investigated for the open channel flow of thickened tailings and a friction factor which is applicable for a wide range of Reynolds number (from 120 to 10,000) and Hedstrom number (from 630 to 45,500) is defined. A minimum required velocity (critical velocity) for total transport in channel flow has also been defined as a function of Reynolds number at equilibrium slope. Based on the new findings, the original beach slope prediction model has been modified and re-presented here