[badpun]

Big hydro requires ungodly amounts of reinforced concrete, labor (to dig millions of cubic meters on earth) and transportation capacity (gotta transport that concrete on site - hard to do with ox-powered carriages on unpaved roads). I can't see say Louis the XIV's France ever pulling that off.

[kjkjadksj]

Despite this, dams and other monumental architecture as well as complicated water management controls were built in ancient times all over the world.