Place to wash up (4)
(Other definitions for sink that I've seen before include "Plummet" , "Scene of iniquity or washing up" , "Fall to the bottom" , "Get worse" , "Plunge down" .)
(Other definitions for shore that I've seen before include "Seafront" , "Land by sea's edge" , "Stay in" , "Country" , "Prop; coastline" .)