The salt water end of the locks is tidal. The walls clearly show how high the water will rise with a combination of algae and barnacles. The barnacles seem to have got themselves well established everywhere. There is a ladder built in to the wall to assist you if you end up in the water and need to get out. However, judging by how many barnacles are now in residence on the rungs of the ladder, I am going to guess that climbing it will be a very painful experience. Maybe there is a better way?