Major bedroom communities in Tokyo area aging more than average across Japan

TOKYO -- The increasing rates in the percentage of residents aged 65 or more in 18 major bedroom communities in the Tokyo metropolitan area are higher than the national average, a Mainichi Shimbun analysis of census and other data has found.

The aging in the "new towns" in Tokyo and the prefectures of Kanagawa, Chiba and Saitama with a population of around 10,000 or more and an area of 300 hectares or more is estimated to advance further, exceeding the national average in eight of the communities.

Those 18 new towns, originally developed before the 1980s to accept newcomers from other parts of the country, face not only aging issues but also a decline in functions as local communities, according to the Ministry of Land, Infrastructure, Transport and Tourism, which is now exploring ways to rebuild those areas. There are 64 such towns nationwide, according to the ministry.

According to census and other figures, the national average for the ratio of people aged 65 or older was 26.6 percent in 2015, an increase of 1.32 times from the 2005 figure of 20.2 percent. For the 18 communities, the growth rates were between 1.33 and 2.34 times.

The community with the highest rate of aging in 2015 was Kemigawa Kaihin in the Mihama Ward of the city of Chiba east of Tokyo, where the figure was 31.8 percent. The town aged quickly, say experts, because as a community built on reclaimed land, its development and acceptance of new residents advanced faster and many residents in similar age groups have become old altogether.

The 2025 estimates, conducted using software developed by the land ministry's National Institute for Land Infrastructure Management, show that eight of the 18 communities in those four prefectures will have aging ratios of between 30.5 percent and 37.3 percent, higher than the national average of 30.0 percent.

(Japanese original by Shin Yasutaka, City News Department)