Ultrafast water transport through graphene oxide membranes (GOMs) is considered to originate from the friction-free movement of water molecules through sub-nanometre graphene-based channels . In detail, GOM nanochannels consist of patches of graphitic and functionalized areas. Along the graphitic parts the water transport is considered frictionless and along the functionalized areas the water transport is partially hindered . The assumption that the water transport is friction-less along graphitic domains originates from the use of the Hagen-Poiseuille (HP) equation to describe the water transport in graphene-based nanochannels. The HP equation allows calculating water flux through a channel if water molecules have zero velocity at the liquid/channel wall interface . This condition is called a non-slip condition. In experiments, the liquids often exhibit slip at the channel walls (i.e., the non-zero velocity at liquid/channel wall interface) . To describe the amount of slip, the slip length is introduced. In particular, the water flux through graphene-based nanochannels showed a large slip length. Hence, it was concluded that the water flux is frictionless. In the case of GOMs, the water transport is only partially frictionless due to patches of functionalized areas. Nevertheless, the GOMs typically show high slip lengths indicating low friction transport along their nanochannels . Recent advances allow a deeper understanding of the unusual water transport along graphene-based planes in nanoconfinement . However, it was identified that the influence of defects on this transport is yet challenging to access experimentally . Ab initio molecular dynamic (AIMD) simulations predict that defects in the graphitic plane will cause extra friction to the movement of water inside the nanochannels .