Wet snow avalanches pose a major threat for people and infrastructure in many regions of the Alps. Compared to dry snow avalanches, little is known and the research is very difficult. One main problem is the prediction of the accurate date of a wet snow avalanche release. Infiltrating water into a snowpack can change its stability very quickly. It is of great importance on which layers the water meets. This work deals with the way water moves through a snowpack, as well as with the change of stability initiated by water infiltration. With dye-tracer experiments we investigate varying infiltration patterns in snowpacks with different layering and liquid water contents. It appears that matrix flow is only observed in ripening snowpacks, consisting solely of melt forms. Apart from that, water percolates downwards in the form of preferential flow channels. The stability around capillary barriers inside the snowpack is investigated with stability tests. It is of special interest whether the fracture takes place in the overhead, water soaked, fine-grained layer, or in the underlying, dryer, coarse-grained layer. It appears that in most cases the coarse-grained, underlying layer, showing lower liquid water contents than the overlying fine-grained layer, collapses. In addition, the change in stability of typical „dry-snow weak layers“ (layers consisting of faceted crystals and depth hoar) with progressive water content is investigated. In relation to the formation of „cold glide snow avalanches“, we analyse whether the grain shape of the basal snow layer has influence on the upward capillary movement of water inside the snowpack. The results clearly show that an uplift driven by capillary forces is only possible in layers consisting of rounded grains. In these layers, water moves upwards several centimetres in a few seconds. In layers consisting of faceted grains and depth hoar, no upward movement of water is observed.