Shimonoseki City Waterworks Bureau Takao Water Purification Plant

A Meiji brick waterworks still on duty

The Shimonoseki City Waterworks Bureau Takao Water Purification Plant is a water treatment plant at 8-1 Kasugacho, Shimonoseki City, Yamaguchi Prefecture, begun in 1901 and completed in 1906 as the heart of the city's first waterworks. Four of its structures, the receiving well, the No. 4 circular filter bed, the regulating well attached to that filter bed, and the distribution reservoir, were entered on the register of Registered Tangible Cultural Properties on January 16, 1998.

All four date from the original 1906 works, and all four are still in service more than a century later. The city describes Takao, together with the Utsui reservoirs, as Shimonoseki's first waterworks and a brick-built one.

A hilltop chosen for supply

Shimonoseki's modern waterworks began with a survey in 1891 by the Scottish engineer William K. Burton, and the design and construction were carried out by Takigawa Kenji, chief waterworks engineer of Osaka. The distribution base was placed on a rise then known as Tōsen in the village of Seki-Ushiroji, today's Kasugacho.

Water piped about 12 kilometres from the Utsui reservoirs was filtered, stored and sent into the city from here. The original Shimonoseki City Waterworks Bureau Takao Water Purification Plant had three slow sand filter beds and a two-basin distribution reservoir, and supply began on January 1, 1906. The city counts this as the ninth modern waterworks in Japan, after Okayama.

When pressure fell on higher ground in the summer of 1914, a further filter bed was added, begun in November 1915 and finished in May 1916. In 1929 a separate plant at Hiyoriyama took over supply to the city's higher districts, leaving Takao to serve the lower ones.

Four structures, in the order the water meets them

The registered structures at the Shimonoseki City Waterworks Bureau Takao Water Purification Plant make most sense if you follow the water.

First comes the receiving well, which the city calls the plant's front door: water from Utsui arrives here and is divided among the filter beds. Next is the No. 4 circular filter bed, a round basin 40.6 metres across where water still passes through sand by slow sand filtration, cleaned by the microbial layer that forms on the surface. Between the filter beds and the distribution reservoir stands the small regulating well, which houses a valve controlling how much water is filtered. Last is the distribution reservoir, where chlorinated water is held before it goes out to the city; its roof is covered with grass.

What ties the four together is the building method: courses of brick finished with granite copings and cornices. The Agency for Cultural Affairs registers all four for their contribution to the historic landscape of the country, and the city notes that the nine Shimonoseki waterworks structures registered in 1998 were the first complete intake-to-distribution chain registered in Japan.

Visiting the Takao plant

The Shimonoseki City Waterworks Bureau Takao Water Purification Plant is an operating facility, and visitors cannot simply walk in. The city asks anyone wishing to see the registered structures inside the plant to apply in advance to the Water and Sewerage Bureau. Applications and enquiries go to its General Affairs Section (083-231-3121); ask about dates and photography when you apply (checked September 2026).

The plant is in Kasugacho, the same district as the bureau's offices. The city gives the nearest stations for the bureau as JR Hatabu or JR Shimonoseki, and the nearest bus stop as Maruyamachō, on routes via Takao or the Maruyama line.

The Waterworks Archive Room, housed in the former Hiyoriyama plant office and registered in the same batch of nine, is a short distance south in Nagasaki Chūōchō. Its displays cover Burton and the history of the city's water supply, and it can also be visited by advance application.