A Study on Co-Management between Legal Manager and Local People of Urban River as Public Space

法律对公民改变河流环境和在没有法律允许的情况下使用河流环境有法律限制。因此，希望河流管理部门和市民共同做好河道管理工作，让市民更好地利用河流，改善河流环境。这项研究旨在考察公民和维护团体继续参与河流当局之间的河流共同管理的可能性。结果总结如下：(1)公民参与河流管理的真实情况调查东海地区地方直辖市河流主管部门和管理农业排灌的土地改良区，以掌握公民参与河流治理规划、河流环境维护和河流活动的真实情况。从参与规划过程、维护和河流活动三个方面，将市民参与河流管理分为7种类型。(2)河流与农业灌溉共治案例为阐明市民参与河流管理的原因，选取了两个案例：一是爱知县丰桥市浅仓河，二是静冈县三岛市根北河，市民和维护团体参与了规划过程，(3)河流共同管理对公民参与河流维护的连续性的影响对东海地区河流维护团体的问卷调查表明，这些团体在需要常规维护的地区和/或其住所附近进行活动。通过对浅仓河与河流管理部门和当地居民的合作研究表明，参与河流管理活动提高了居民对河流的关注度，激发了居民持续参与的意愿。

There are legal restrictions for citizen to change river environments and to use without acts which law allows. Therefore it is expected for river authority and citizen to do cooperatively river management, for citizen to use river variously and improve river environment. This research tackled to examine a possibility that citizen and maintenance groups would keep participating in river co-management between river authorities. Results are summarized are follows :(1) Real condition for citizen to participate in river managementQuestionnaires were carried out to river authorities of local municipalities in Tokai area, and Land Improvement Districts which manage agricultural irrigation and drainage, in order to grasps real condition of citizen participation in planning of river improvement, maintenance of river environments and activities in a river. 7 types of citizen participation were classified with the combination of the participation in planning process, maintenance and activity in a river.(2) Case studies of co-management of river and agriculture irrigationTo clarify the reason for citizen to participate in river management, two cases were selected : first is the Asakura River, Toyohashi city, Aichi prefecture, second is the Genbei River, Mishima city, Shizuoka prefecture, which citizen and maintenance group participated in planning process, maintenance and activity in a river.(3)Influence of river co-management on continuity of citizen's participation in river maintenanceQuestionnaire to river maintenance groups in Tokai area clarified that those groups kept activities in the areas to be conventionally maintained and/or near their residence. And research of Asakura river which tackles river management cooperatively with the river authority and local residents could suggested that participation in the river management activities made the residents' concern for the river improved, and inspired continuous participation intention