Implications of Centralized Compact City Designs for Accessibility from Simulation Analyses:

Abstract

Recently, governments of some cities have adopted urban policies, based on a compact city concept to facilitate accessibility, mainly for mobility-impaired people among Japan's ageing society. The government of Aomori city has planned a popular compact city model, or a centralized urban physical structure, by controlling the urbanized area of the Mid-city zone (populationincentive zone) in the city master plan established in 1999. The effects of measures for providing accessibility to the central railway station as a representative facility of the city center are analyzed, and the implications for urban policy based on a centralized compact city design in Aomori city are investigated. Accessibility, as represented by time-distance to the central station, is measured based on a road network analysis and timetables of train and bus services. As a result, it is observed at a level where most of the population can reach the facility. The simulations are based on the following measures: 1) supporting migration inside of the Mid-city from the Outer-city forming the suburbs; and 2) improving the frequency of bus transportation in the Toyama housing district, a case-study area in the suburbs. The major findings are as follows. 1) Accessibility to the central station by train is improved with migration and the effects are greater for elderly people. It seems to be useful to strengthen these effects if migration is only into the Inner-city. Although variations in migration measures are found under several conditions, accessibility is finally improved to almost the same level. Therefore, it is important to continue migration support measures, even if the pace is slow. 2) Accessibility to the central station by bus from the Toyama housing district is improved substantially under a situation where the frequency of bus services is increased until five-fold. The effect is also improved for elderly people. Some suburban cores such as large housing districts should be set or maintained at least the short-term aims of urban policy, because the population is already distributed in the suburbs and the level of functions of daily life should be maintained there.

Overview: Current States of Non-metropolitan Cities in Japan

“…He argues that restructuring the centralized government system is necessary to change migration patterns and mitigate depopulation in peripheral regions. Akimoto (2016) performs a simulation analysis on the effects of population centralization and high frequency of bus transport on improving accessibility to the central area for citizens in Aomori city, which is one of the cities that introduced a compact city policy at an early stage in Japan. As a result, she points out that the effects of population centralization will be enhanced by focusing it on aged people, and the high frequency of bus traffic will contribute significantly to improving the accessibility of aged people.…”