著者

矢根 眞二

出版者

桃山学院大学

雑誌

桃山学院大学総合研究所紀要 (ISSN:1346048X)

巻号頁・発行日

vol.37, no.3, pp.151-172, 2012-03-30

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The purpose of this paper is to clarify the investment requirements to replace old water pipes, which are the main capital stock within the supply structure of Japanese drinking water suppliers. This is an urgent issue because these updates are overdue. As a result, I have derived four important implications. First, bulk water suppliers' sustainment of their dam-water purification capacity and water suppliers' conservation of ground water are indispensable to maintaining the current supply system. Second, water suppliers need to spend an average of 920 million yen per year for the next half-century in order to maintain the water pipes currently in use. If they add this spending to water rates, the average water rate nearly doubles. Third, the majority of these water suppliers use aged water pipes that have actually exceeded their legal working life. In order to renew these pipes, water rates would need to be 4.5 times as much as they are now. Fourth, although a prompt regulatory reform is desired due to the difficulties faced by small-and-tinysized utilities in trying to solve these problems on their own, political conventions prevent these reforms by delaying them. The fact that these conventions themselves are the root of the problem is a grave issue.