Guide to Kaduma Anazeki

Kaduma Anazeki Headworks

Kaduma Anazeki Land Improvement District
Midori Net Kaduma

History of Kaduma Anazeki
The history of trunk channel of this land improvement district dates back to 1599, when
the Nambu Feud ordered Jinroku Kamatsuda, an expert minor, to drill an 11-meter long,
1.8-meter wide tunnel through Tsurugi-nagane, a series of cliffs of Mt. Yuzaka-yama andconstruction a dam, to take water from the Shizukuishi-gawa River to develop paddy fieldarea to improve management of the fued. Two years before that, Nobunao Nambu, the 26th
feudal lord of Nambu Feud began construction of a new castle to move the capital of the feudfrom Sannohe (now in Aomori Prefecture) to Kozukata (now in Morioka City), then the feud
needed to develop new paddy fields. This official dam for irrigation of Nambu Fued is theprecursor to the Kaduna Anazeki Headworks. The rice cultivated and harvested from paddy
fields irrigated by water from this dam was said to be of the best quality of all rice producedin the feud and was all stored in the feud’s rice storage houses.
This official dam for irrigation was named Kuduma Dam, because the dam was built toirrigate the area formerly called Kaduma-mura Village.
Thereafter, lateral channels were added one by one to the irrigation channel from
irrigation dam in association with the tunnel expansion works done in 1670 by Jinshichi
Yoshida, the first dam chief, with supports to drilling of the Kaduma Shinseki (Kaduma NewDam) by the feud, and repeated efforts of the feud to develop new paddy fields. A historical
document “Nambushiyou (meaning Nambu History Summary)” (published in 1911) says
“The area irrigated by the system is very wide, with several tens of lateral channels, of which
the most outstanding are four villages; namely, Kami-kaduma, Naka-kaduma, Shimo-kaduma,Shin-kaduma, and extending to both Iwate and Shiwa Counties. The upland fields that wereconverted to good paddy fields by this irrigation system were significant, amounting to 30
thousand koku or more (one koku is almost equivalent to about 180 liters) in terms of riceproduction.

Former Kaduma Anazeki Headworks

Water intake at the former Kaduma Anazeki Headworks–1–Many years thereafter, in 1886, during the Meiji Restoration after abolishment of the feud
administration system, the Kaduma Anazeki Irrigation Dokoukai was established to take overthe management and maintenance of the official feud dam. In 1894, the Kaduma Anazeki
General Irrigation Association (1st stage) was established, thereby the management of thedam was delegated to the private sector for the first time. Further, in 1910, the association wasreformed to the Kaduma Anazeki General Irrigation Association (2nd stage), the precursor tothe Kaduma Anazeki Land Improvement District. After enforcement of the Land
Improvement Law in 1949, the association was reformed in 1951 to make a fresh restart asthe present Kaduma Anazeki Land Improvement District.
During these years of transformation, the Kaduma Anazeki Arable Land Union wasestablished in 1926 to excavate lateral channels that branched from the Kaduma Main Damand the associated arable land reform. In 1947, on completion of this project, the union
merged with the Kaduma Anazeki General Irrigation Association, precursor to the Kaduma
Anazeki Land Improvement District. The Kaduma Anazeki Land Improvement Districtexpanded through a series of mergers in 1949 of the Shinyamano Arable Land Union which
was established in 1920, in 1971 of the Kemuriyama Land Improvement District, and in 1975of the Fudou Land Improvement District. In 1985, duplication with the Sannoukai Land
Improvement District was resolved.
The Kaduma Anazeki Land Improvement District has been purchasing mountain forest
areas in Ohshuku Area, Shizukuishi-cho Town, Iwate County and developing headwater
forests since 1928, when it was yet a general irrigation association, to conserve the water
source area of the Shizukuishi-gawa River, from which the irrigation water is taken. The
headwater forest belonging to the Kaduma Anazeki Land Improvement District now amounts
to 233 hectares, and form beautiful forests of Japanese cedars, Japanese trees of genus
Zelkova, etc. In 1987, the Kaduma Anazeki Land Improvement District was decorated by theprime minister for contribution to promotion of greening.

Headwater forest–2–

Although this land improvement district has a long history, with its origin as management
and maintenance of water channel for irrigation of the Nambu Feud’s official irrigation water
dam system, it is now quite modern in its facility, as a result of a series of works explained
below. In 1953, the “Shizukuishi-gawa River Irrigation and Drainage Improvement Project,”a prefectural project, started, followed in 1960 by the start of the “Shizukuishi-gawa River
Area Agriculture Irrigation Project,” a central government’s project. These projects improvedand expanded the main channels, which were originally dug by traditional and primitive
methods without timbering, and converted them into lined channels, improved the headworks,
built new dams. As a result of all these efforts, the improved system now irrigates about 5,000
hectares of paddy fields in its area of jurisprudence.
After completion of these projects, problems still remained to be solved. These are
obsolescence of facilities that had been in prolonged use after completion, instability of watersupply in the western part of the project area where water supply had been dependent uponsmall streams. To correct such situations, the “Morioka Southern Area Agricultural Water
Utilization Project,” a second-stage central government project, started in 1989. Thereafter in1995, a land reform prefectural project done in association with the central government
project started to install new irrigation channels and drainage canals, to separate irrigation
channels and drainage canals, to install pumping stations and new irrigation channels in thewestern part of the project site, thus realized stable supply of irrigation water, thereby
contributed to stability and modernization of the local agricultural economy.
The Kaduma Anazeki Land Improvement District consists of Morioka City, prefecturalcapital, Yahabe-cho Town, Shiwa-cho Town. Recently, there is a tendency of population
being concentrated in urban surroundings, which causes agricultural land in urbanization
promotion areas to be converted into residential sites. Along with such trends, problems prone
to be caused by urbanization, such as discharge of foul water into irrigation channels anddrainage canals, are becoming serious. In 1984, the land improvement district establishedjointly with the city and town governments in the area of jurisprudence the Kaduma Anazeki
Area Irrigation Channel, etc. Utilization Coordination Conference, and discussing
countermeasures, etc.

Inariba Large Diversion Work–3–Against the background of ever rising expectation on the part of people for realization ofmultifunctionality––“such as natural environment conservation, headwater conservation”––
of agriculture and agricultural communities as an element of the movement towards 21st
century Land Improvement District Development, the land improvement district conducts
activities for maintenance and conservation of environment of the channel side parks aroundthe Kaduma Anazeki Headworks, as an effort to have the importance of this facility better andextensively understood by as many people as possible, with a view to realizing attractive andrich agricultural communities. These activities––cleaning of channel side parks, for example,
so easy that everyone can do––are done in cooperation with community people andorganizations. The land improvement district will intensify such activities, in other places forexample, and thereby intensify activities for promotion of 21st century Land Improvement
District Development movements.

Planting activity near Kaduma Anazeki Headworks–4–Kaduma Main Dam

Tama chanCompiled and published byKaduma Anazeki Land Improvement District–5–