Multiple Evaluation in the Future Population Distribution for Sustainable City

Abstract

Recent years have seen a decrease in the population of Japan. If urban areas continue to expand to the suburbs with this depopulation, various urban problems will arise including difficulty of maintaining public transport system and increase in energy consumption. To address this, compact urban structure is proposed, corresponding to the decreasing population. Actually, Japanese government announced, in 2014 guideline and policy for compact city. This encourages local governments to decide "inducing area for urban functions" in which urban functions should be concentrated and "inducing area for dwelling" that should attract residents. However, it is not clear where these areas should be located. It is important to examine the positive and negative zone for living in term of various perspectives and future urban structure should be designed based on the evaluations. This study aims to examine the high potential area for living in term of six viewpoints such as public transport convenience, disaster risk, environmental load, infrastructure cost, economy and convenience of welfare and medical facilities and create scenarios by concentrating population to efficient zones classified by cluster analysis with evaluation data. Finally, the scenarios are evaluated in the same method and compared to assess the impact of compaction on some indexes and differences from BAU. Results show that cluster 2 zones (around the inside of urbanization areas) are higher positive potential in all indexes. The scenario compacted based on all evaluations is more efficient in all aspects than BAU. However, other scenario compacted based on one criterion has tradeoff between other indexes.