ON THE DISTRIBUTION OF THE WATER-UTILIZATION GROUPS AND THE UTILIZATION REGULATIONS IN THE NARA BASIN

There have been many groups of irrigation water utilization called Ike-go or Ide-go in the Nara Basin. These groups consist of several villages, with two influential ones called Kagimoto and Izukasa as their centers, thus constituting strongly united bodies. Some villages or groups enjoy greater water rights than others, and this has brought about division of classes. With many water-utilization groups distributed, and strict customs controlling them, the regula-tions are laid down for water utilization of the basin. Construction of modern dams and ur-banization have caused less strict customs, resulting in re-organization of the regulations. 1) There are 96 Ide-go groups, 40 Ike-go groups, and 9 drainage groups out of a total of 145 water-utilization groups. The total number of villages joining these kinds of associa-tion is 360, occupying 78 per cent of the villages in the basin. These average number of constituting villages in Ide-go or Ike-go is 3. The largest constituting villages in Ide-go is Jukka Ide-go along the River Tondo and it consists of 9 villages with 175 ha of irrigation area. As for Ike-go, Hatao Ike-go which consists of 7 villages and Kodai ji Ike-go with 6 villages are the largest ones. In most cases, the irrigation area of each groups is less than 50 ha. The area or extent of the Ike-go groups is smaller than that of Ide-go, because Ike-go has not a few storing reservoirs with shallow bottoms and therefore with smaller volume of water is kept in them. The Ide-go groups are comparatively densely distributed in the south eastern part of the basin where the Hase River flows in the middle. In the southern part of the basin 75 groups are distributed, occupying 80 per cent of the total. The Ike-go groups are compara-tively sparsely distributed in the northern and southern parts of the basin where irrigation ponds are found. Both groups are not so large because rivers are short and their water volume is small. These areas were divided into complex manors and feudal domains in the past, thus making irrigation development difficult. 2) About one-third of the villages join two groups or more. Some of them even join both irrigation group and drainage one whose functions are utterly opposite, thus making their respective relations and interests quite intricate. Villages joining two groups or more are mainly distributed along rivers which seem to act as regulations for irrigation water use. This complexi-ty of the regulation is a local peculiarity and a characteristic of farming districts of the Nara Basin. Moreover, in the lower area extending from the middle to the western part of the basin, many drainage groups are to be found. Even among these groups there are some vil-lages which join irrigation groups, thus showing the further delicate mutual relations and interests. 3) The origin of the organization of the groups of irrigation water utilization is old, being already found in the medieval ages at many places, especially on the foot of mountains where they could easily get water. The Iwai Rivers and Anashi are the cases. As the development of the basin area (e. g. construction of conduits as well as reservoirs) proceeded, many groups were organized for irrigation water use. Of them, there are such influential villages as Kagi-moto and Idemoto, governing the remaining ones. These governing villages occupy the places where powerful families once lived in historical days and where they could enjoy the ad-vantages of geographical positions, hence the gradation of various kinds and even discriminations between the governing villages and others. In some cases, hierarchically arranged villages stand side by side with Kagimoto in the center. In the case of Ide-go, villages upperstream enjoy greater advantages than those downstream and the latter often are under the control of the former, resulting in the formulation of the regulations for water utilization.