Reed boats seem very exotic to Westerners, who only see them in books about Ancient Egypt or remote Lake Titicaca, but river boatmen in Ireland used reeds to make dramatically simple and effective sculling boats known as cliath thulca until recent times.
In 1962 the National Museum of Ireland commissioned one from Patrick Gately on the River Suck, County Roscommon. He produced a boat that is simple, effective and about as sustainable as you can imagine.The reeds are gathered into long bundles which form a raft. On top is a wooden frame that stops the edges of the raft from folding upwards and supports the rowing thwart and rowlocks. It is the minimal boat.
In former times the frame would have been made of basket work. Presumably the frame would have been kept and the reeds renewed each year.
It is easy to imagine boats like this being used anywhere where reeds and willows grow. There are reed beds and willows at the top end of the harbour close by here - I am strongly tempted to build one. I could probably get an Arts Council grant....