震災被災者による都市河川での応急取水活動と水辺空間に関する研究

Abstract

In this report, the author chooses the Umeda River of Sendai city as an example and investigates the actual situation of the water-drawing activity by victims of the Great East Japan Earthquake. The investigation was conducted by interviewing or collecting questionnaires from the victims. The subjects of the survey were the local inhabitants and managers of public-accommodations of the neighborhoods adjoining the Umeda River. These investigations yielded the following results. 1) In the areas where the water supply was cut-off for more than a week, approximately 30% of inhabitants drew water from the river. In addition, in the public accommodation that became a base of refuge and restoration support, the manager too drew the river water. Victims from afar too would travel by cars to water. 2) The local inhabitants mostly drew water from the river in groups of two people twice a day, drawing an average of 23L per trip (total approximately 46L/day). By dividing this quantity of water by the mean household number of people, this worked out to around 13L/day per person. 70% of the water drawn was carried on foot. The enforcement period of the water drawing was an average of six days. 3) 90% of the local inhabitants chose the site of their water-drawing activity based on its proximity to their homes. In addition, the mean-transportation distance from the waterside to their home was 217 m. 4) The public-accommodations managers mostly performed water drawing from the river in groups of around three people twice a day (totaling approximately 70 L/day or 35 L per trip). 80% of water conveyance was done by a chassis. The enforcement period of the emergency water intake was an average of 12 days. 5) "18 access points” existed in the area where the water supply was cut off for more than a week, and water drawing was carried out at 13 of those points. In other words, it was revealed that access points were useful in areas that needed water. In addition, water drawing activity was carried out at 12 other points on the waterside that were harder to access, and three other points situated on top of a bridge. 6) In the area where water-drawing was heavily practiced, the event that always featured the theme of a river was carried out lively. This fact showed that an everyday river experience led to an understanding of water-drawer-activity enforcement the time of the earthquake disaster. 7) Users came from distant areas to the waterside adjacent to a major road with much traffic. This fact showed that the an access point was particularly effective at such a place. 8) The waterside that was hard to access existed among them and served as a base for the river-cleaning activity by the neighborhood inhabitants. In the case of such a waterside, it was difficult for a site generally recognized as a water-drawing site to be confirmed. Improvement of such watersides is necessary as soon as possible.