An upward erosion/piping action into an embankment or foundation (possibly leading to a breach). Stoping occurs if the piping process is impeded or terminated prior to reaching the reservoir (by encountering non-erodible material, or the occurrence of a roof collapse). Either there will be no further detrimental consequence to the dam, or the horizontal seepage/piping component could translate upward by stoping, possibly intercepting the reservoir or resulting in sinkholes.