積雪寒冷地における農業水利施設の送配水機能の改善と構造機能の保全に関する研究

摘要

我が国の食糾共給拠点となっている北海道においては、積雪寒冷な気象環境と泥炭などの特殊な土壌が広域に分布しているという地域特性に応じた技術開発を進めながら、農業基盤整備を実施してきた。これからは、整備してきた農業水利施設などの機能・性能を長寿命化するための適切な維持・予防対策および農業用水の需給変動に対応できる機能を確保するための技術開発を求められている。 農業水利施設は送配水機能とそれを支える構造機能より成っているがこれら機能を保全するためには、土地利用動向と水需要の変化の把握、冷害対策などの水田水需要のへの対応、高水圧を有する大規模畑地灌溉施設の維持管理、積雪寒冷な気象条件や泥炭などの特殊土壌からなる地盤条件に対応する調査・設計や改修のための技術開発が課題である。 このため、本重点プロジェクト研究では水田灌溉施設の送配水機能のp評価・改善技術を開発するとともに、畑地灌溉施設の予防保全技術の開発を行う。また、積雪寒冷地域の特性を反映した農業水利施設の構造機能の診断方法および補修・改修技術の開発と、泥炭地盤における管水路の新たな設計手法を確立する。これら、一連の研究成果として、予防保全技術としての補修•改修計画作成手法の提案および、水田灌漑における効率的で安定した送配水機能を確保するための施設の操作方法の提案を行うものである。%Agricultural infrastructure improvement of Hokkaido where is a food supply center in Japan has developed along with technological advancement applied to regional characteristics, which include the area's cold snowy climate as well as its extensive peat and other unusual soil. Against this background, there is an increasing need for qpropriate maintenance and protection measures to ensure longer life for irrigation facilities and other infrastructures, and for technological development to secure functions for dealing with variations in demand for agricultural water. Irrigation fecilities consist of water conveyance/distribution and related structural functions. A challenge to be addressed in promoting the maintenance of these functions involves technological development to clarify changes in land use trends and water demand, to cope with fluctuations in water demand for paddy fields due to measures taken in order to protect rice plants from cold-weather damage and other reasons, to support the maintenance and management of large-scale upland irrigation facilities with high water pressure, and to enable surveying, design and improvement of fecilities in cold snowy climates and in peaty ground and other unusual soils. Accordingly, this priority research project is to develop technologies for the evaluation and improvement of water conveyance/distribution functions relating to paddy field irrigation facility and for the implementation of preventive maintenance relating to upland irrigation fecilities. It is also designed to advance the development of a method for diagnosing the structural functions of irrigation facilities suited to the characteristics of cold snowy regions and technologies for repair and improvement related to such functions, and to establish of a new design approach involving the verification of methods for designing and constructing water pipelines in peaty ground. From a series of research fruit a method for planning related repair and improvement and a technique for operating irrigation systems to secure efficient and stable water conveyance/distribution functions for paddy field irrigation is proposed.