ABSTRACT
364The history of aqueducts in Japan is not so long as that of ancient Romans or the “Karez” in the Central Asia. Japanese Society for Civil Engineers (JSCE) and Japan Water Works Association (JWWA) have compiled and published several technical reports from the historical point of view (JWWA 1967; JSCE 1995). The former picked up 13 cases as the monuments and the latter quoted 40 cases as the historic projects. The most of the cases that were recorded in archives came after the late fifteenth century. The reasons for this are as follows: Japanese population of cities in the Ancient Period to Medieval Period was such smaller, that is, less than 100 thousands, with a few exceptions. The cities were built on the alluvial plains (i.e., river deltas), where residents could easily receive clean water from wells or streams nearby.
