Although the local blacksmith was not involved in the manufacture of precision tools, he did, however, contribute significantly to the construction and maintenance of the various mills. He made the axes that felled the trees, as well as some of the metal parts used in the mills. I believe that designing a sawmill or a flour mill and building every part from scratch was a phenomenal accomplishment. Try to imagine a modern engineer setting up a small factory by making every unit by himself and then assembling them. First, the millwright had to choose the location of the mill.
Logs are hard to move by sheer manpower.
There were no tractors. In the case of a broken leg or other severe injury, there was no doctor around. Another engineering feat associated with all water-powered mills was the design and construction of the sluiceway, an artificial channel to conduct the water, complete with valves or gates to regulate the flow. It was built with planks and a staging which supported it. The building of the sluiceway, over rugged terrain and considerable distance, was considered almost as difficult as building the mill itself.