Simulating liquid water flow in snow has deserved much attention in the physics based snow modelling community, as it is a crucial factor in understanding hydrological processes in alpine catchments, snowpack stratification and wet snow avalanche formation processes. Those type of models are increasingly applied for ice sheets and remote sensing retrieval algorithms. Recent laboratory experiments on liquid water in snow has resulted in important advances in simulating liquid water flow in the physics based SNOWPACK model by using Richards equation in natural snow covers. This approach improved several aspects of liquid water flow in snow, for example in simulating the outflow at the base of alpine snowpacks as well as representing the diurnal and seasonal cycle of bulk snow liquid water content. Richards equation can explicitly solve for ponding conditions and subsequent water accumulating on microstructural transitions inside the snowpack. This is considered a prerequisite for the formation of preferential flow paths and we use these concepts to develop a preferential flow formulation for the SNOWPACK model. This new formulation was found to be crucial in the formation of dense ice lenses or ice crusts inside the simulated snow cover. The simulated stratigraphy was found to be in good agreement with snow pits made in the field. The successful simulations of internal ponding and fast transport mechanisms in snow are believed to be a prerequisite to understand larger-scale meltwater fluxes on glaciers and ice sheets.