The protective harbour constructions have an essential impact on morpholithodynamics of the adjacent area of coastal zone. Being artificial capes, port piers make for secondary breaking up of coastal line and, as a consequence, reduce the longitudinal proportion of deposit transport in coastal zone and increase the transverse one.

The supply of large volume of soft technogenic material into coastal zone leads to intensification of alongshore sediment transport and to its accumulation. In result the coastal cliff stabilizes, and valuable sites of coastal zone persist safe from abrasion.