“Case Study: Floating top marks for piles in flooding rivers” –Marine Link

Image: Grupo Lindley / Administração dos Portos do Douro, Leixões e Viana do Castelo

Definitely not in my wheelhouse since I never did inland aids to navigation, but Marine Link reports an innovation in marking shallows and narrow channels in flood prone rivers. Apparently it is a hybrid between marking with a pylon mounted aid and a buoy.

Thanks to Lee for bringing this to my attention.