Sayama-shi

In the latest Population Census the population is about a hundred and forty-nine thousand (148,699 in 2020). Its course is a gentle decline. From 161,460 in 2000, through 158,074 in 2005, 155,727 in 2010 and 152,405 in 2015, to 148,699 in 2020, it fell by about twelve thousand over twenty years. A population that had exceeded a hundred and sixty thousand fell below a hundred and fifty thousand.

Looking inside the figures, the form of a mature residential city of the Tokyo outskirts appears. The share aged 65 and over rose by nearly twenty points over twenty years, from 12.5% (2000) to 32.1% (2020), passing three in ten. It is a steep slope, mirroring how a young generation moved in all at once in the period of rapid economic growth and that generation has all entered old age together. The household-with-children share is 17.7% (2020), and the Childcare Waitlist was 12 in 2025. The Fiscal Capacity Index was 0.85 in fiscal 2023 — a high level covering more than eight-tenths of expenditure with its own tax revenue. The figure of the town of Sayama tea, gently losing population and steeply deepening its aging while keeping fiscal stamina on the high side, appears in the numbers. Why it took this form cannot be read without going back over the history of Sayama tea and the automobile factory.

Sayama’s skeleton is set by the Musashino plateau through which the Irumagawa River flows, and by the two industries that supported that land. The old layer is tea. The Sayama tea raised in this area has been counted, alongside the tea of Shizuoka and the tea of Uji, as one of the three great teas of Japan. Sayama-shi is one of the main production centers of that Sayama tea. The plateau, where tea fields spread, set the town’s old foundation. Along with this, the festival of the Irumagawa Tanabata has long taken root in this town. Its origin is said to go back as far as the mid-Edo era, and as one of the foremost Tanabata festivals of the Kanto it has colored the summer nights. When a railway ran through and a station opened in 1894, the turnout from the neighborhood was added, and the festival came to bustle all the more.

And in the modern era, another pillar rose in this town. In 1964 a certain automobile company opened its first dedicated factory for making four-wheel vehicles in this land. Thereafter this factory supported the town’s economy for more than half a century as a base of four-wheel making. But that factory ended four-wheel production at the end of 2021, and its function was consolidated into a factory in another town within the prefecture. Holding an old foundation as a tea-growing land and, in the modern era, an automobile factory — this town’s form stands upon the history of tea and a factory that the geography of the Musashino plateau held.

What characterizes Sayama-shi is that, while holding the two footings of Sayama tea and an automobile factory, as a residential city of the Tokyo outskirts it gently loses population and steeply deepens its aging. From 161,460 in 2000 to 148,699 in 2020, it fell by about twelve thousand over twenty years. In the period of rapid economic growth, a young generation moved in all at once to this town within commuting distance of Tokyo, and that generation now has all entered old age together. That the share aged 65 and over rose by nearly twenty points over twenty years, from 12.5% (2000) to 32.1% (2020), is the expression of that generation’s wave turning straight into aging.

On the other hand, its fiscal stamina is kept on the high side. A Fiscal Capacity Index of 0.85 is a high level for a regional city, covering more than eight-tenths of expenditure with its own tax revenue. The income of residents as a residential city of the Tokyo outskirts, and the tax source of establishments such as the automobile factory, can be read as having supported the town’s finances. Yet how the impact of the factory that ended four-wheel production will reach the future tax source is a point that will appear in figures to come. The population gently declines, the aging steeply deepens, and yet the fiscal stamina stays on the high side — these three that the town of tea and a factory shows mislead the reading if taken one at a time.

Sayama holds several functions on a single plateau. One is the history of being a main production center of Sayama tea, one of the three great teas of Japan alongside Shizuoka and Uji, holding the old layer of tea fields spreading across the plateau. Another is the Irumagawa Tanabata, going back as far as the mid-Edo era, keeping the character of the bustle of summer nights. And the dedicated automobile factory, opened in 1964 and ending four-wheel production at the end of 2021, inscribes the distinctive structure of the rise and fall of an industry on this town.

From a plateau of a tea-growing land, to a residential city of the Tokyo outskirts, and on to a town holding a four-wheel factory — the condition “a Musashino plateau close to Tokyo” raised tea, called in a residential city, and took in an automobile factory. On the Irumagawa plateau, the tea fields that do not move and the factory that did move coexist. An industry that strikes its roots into the land, and an industry that leaves on a single management decision — having stood on two legs of utterly different nature has made the swing of the town of Sayama.