A benchmarking study of four numerical runout models for the simulation of tailings flows

Sci Total Environ. 2022 Jun 25;827:154245. doi: 10.1016/j.scitotenv.2022.154245. Epub 2022 Mar 4.


Numerical runout models are important tools for predicting the potential downstream impacts of tailings dam breaches that generate tailings flows, which is a crucial step in emergency preparedness and planning, and risk management. Most existing runout models were originally developed for the analysis of water floods or flow-like landslides (e.g. debris flows). In this study, we back-analyze two well-documented historical tailings dam breaches (1985 Stava, Italy and 1994 Merriespruit, South Africa) using four numerical models (DAN3D, MADflow, FLO-2D and FLOW-3D). The main objective of this multi-case, multi-model benchmarking exercise is to identify collective opportunities to adapt these types of models and associated modelling methods to tailings dam breach runout applications. Comparing best-fit simulation results, we find that all four models are capable of reproducing the bulk behaviour of the real events; however, (i) multiple sets of rheological parameters may produce very similar output results, (ii) the best-fit input parameter combinations are non-transferable between models and inconsistent with independently measured rheological properties of stored tailings, and (iii) choosing an appropriate set requires sufficient understanding of material rheological properties and expert judgment. Using a systematic sensitivity analysis with the First-Order Second-Moment (FOSM) approach, we also find that each model is sensitive to different input parameters, although the total released volume is among the main high-influence parameters in every scenario. We conclude that more case study back-analyses are needed to enhance our understanding of these sensitivities and develop better guidance on the use of these types of numerical models for tailings flow runout prediction.

Keywords: Benchmarking; First-order second-moment; Numerical modelling; Runout analysis; Sensitivity analysis; Tailings dam breach.

Publication types

  • Review

MeSH terms

  • Benchmarking*
  • Computer Simulation
  • Italy
  • Water
  • Water Pollutants, Chemical* / analysis


  • Water Pollutants, Chemical
  • Water