Genbegawa Irrigation Canal is the irrigation canal with 1,500m length and 8m elevation difference. The water source is spring water from Mt. Fuji coming from Mishima city park Rakujuen-kohamaike pond, which is registered as Japanese national nature treasure and a beauty spot. The water comes to Nakazato-onsuichi pond at the lower part of the basin to raise its temperature and then is distributed to the rice field area of Nakazato district for agricultural use.
It was named after Genbe Terao, who was an influential leader of Mishima district. He made the canal to lead spring water from Kohama pond and to irrigate broadly to the agricultural field of 11 villages of Nakazato area in Mishima city, where people were suffering from lack of water and bad crop. The canal from Kohama pond to Nakazato district was created by using geographical features fully so water runs high points of the land. Therefore when it rains heavily, muddy water has been prevented from getting in the canal.
Moreover upper part of Genbegawa Irrigation Canal is wide and shallow for warming up the cold water of 15 degrees Celsius. Along the river side, shrines of a water god and wooden piers called Kawabata were built. The piers were used, for example, when they had rites to purify souls by releasing bowls in the river at the time of Hamaori bowl releasing rite of Bon week (Japanese ritual week for worship to ancestors’ souls). Riverine residents led spring water in the canal to their house and used for cooling food, cooking and washing.
However, since 1960s, ground water had been drawn at upstream a lot so the water amount in the canal drastically decreased. In addition to that, waste water from households and dumping made the canal dirty.
During 1990-1997, “ecology-up” project and “water road between city and village” project had been made and executed by the local authority’s initiative. Shores covered with concrete blocks were replaced to original shore protection with stones and soil. The environment got close to the natural condition. NPO Groundwork Mishima was found in 1992. It promoted cooperation among various sectors and then a company offered its skill for water improvement. The efforts resulted in the current water environment with rich biodiversity, which is appreciated as a successful model of diversified agricultural facility.