Handayama Water Distribution Area Construction Water Meter

Handayama Water Distribution Site Original Metering Room: A Jewel of Meiji-Era Water Engineering

Nestled on the hillside of Handayama in Okayama City, the Original Metering Room (Sōken Ryōsui-shitsu) of the Handayama Water Distribution Site stands as a charming testament to Japan's early modern waterworks. Built in 1905 (Meiji 38), this diminutive hexagonal brick structure was once the nerve center for measuring water flow to the city below. Today, it survives as a Registered Tangible Cultural Property, offering visitors a rare glimpse into the infrastructure that transformed public health in one of Japan's pioneering water-supplied cities.

A City's Quest for Clean Water

Okayama's journey toward modern waterworks was driven by urgent necessity. The city, built upon the alluvial deposits of the Asahi River, suffered from persistently poor groundwater quality, leading to repeated outbreaks of cholera and other waterborne diseases throughout the late 19th century. In 1890, the British engineer W.K. Burton was invited to conduct surveys and draw up plans, but financial constraints and devastating floods shelved the project.

The impetus returned in 1897, when Mayor Oda Yasumasa enlisted the renowned naval engineer Yoshimura Chōsaku and the civil engineer Sano Tōjirō to design a comprehensive water supply system. Construction began in 1903, and despite setbacks caused by the Russo-Japanese War, the system was completed in 1905. On July 23 of that year, a grand ceremony was held at the Handayama distribution site to celebrate the commencement of water service — making Okayama the eighth city in Japan to establish a modern waterworks, following Yokohama, Hakodate, Nagasaki, Osaka, Tokyo, Hiroshima, and Kobe.

Architectural Features of the Original Metering Room

The Original Metering Room is a single-story brick building with a regular hexagonal plan and a floor area of just 8.9 square meters. Despite its compact size, the structure displays a surprisingly refined architectural vocabulary. Brick pilasters articulate the six corners of the hexagon, lending visual rhythm and structural stability to the walls.

The main entrance is crowned by a triangular pediment embellished with a keystone motif at its apex, framed by classical orders — a composition clearly inspired by Western architectural traditions that were being enthusiastically adopted in Meiji-era Japan. On the remaining wall panels, circular windows framed in locally quarried granite create an elegant contrast between the warm red of the brick and the cool white of the stone. This distinctive combination of red brick and granite is a hallmark of the entire Handayama water distribution complex and the adjacent Mino Water Purification Plant.

Inside, the room originally housed a Venturi-type water meter, an instrument used to measure the volume and flow rate of water being distributed from the hilltop reservoirs to the city. Though the meter is no longer in use, the building itself remains in excellent condition, a tribute to the quality of its Meiji-era construction.

Why It Is Designated as a Registered Tangible Cultural Property

In December 2004, the Agency for Cultural Affairs determined that ten waterworks-related structures in Okayama City merited registration as Tangible Cultural Properties. The Original Metering Room was officially registered on February 9, 2005, along with the three circular reservoirs, the additional metering room, the former office building, and several structures at the Mino Water Purification Plant.

The significance of the Handayama complex lies not only in the age and rarity of its individual structures but also in the completeness of the surviving ensemble. Facilities spanning the entire water treatment process — from intake and filtration to pumping and distribution — remain intact, many still in active operation. This makes the Handayama and Mino complex one of the most comprehensive surviving examples of early modern waterworks in Japan. The Original Metering Room, with its refined Western-influenced design and its role in the measurement of water distribution, is an integral part of this nationally important group of heritage structures.

Highlights and Things to See

The Original Metering Room is located within the grounds of Handayama Botanical Garden, making it easy to combine a cultural heritage visit with a relaxing stroll through one of Okayama's most beloved green spaces. Here are some highlights not to miss:

• The elegant hexagonal form of the Original Metering Room, with its classical pediment, granite-framed round windows, and warm red brickwork — a perfect subject for photography enthusiasts.
• The nearby Additional Metering Room (Zōsetsu Ryōsui-shitsu), built in 1939, which imitates the original's hexagonal design in reinforced concrete with brick-patterned tile cladding, offering a fascinating comparison of Meiji and Shōwa-era construction techniques.
• The three circular reservoirs (Nos. 1–3), rare examples of domed brick-and-concrete cisterns with diameters of approximately 21 meters, two of which date from 1905 and remain in active use.
• The Former Office Building (Kyū Jimusho), a wooden single-story structure with Western-influenced window designs and the Okayama city crest worked into the ventilation grilles.
• The Okayama Waterworks Memorial Museum (Suidō Kinenkan), housed in the former boiler room and pump station at the adjacent Mino Water Purification Plant — a hands-on facility where visitors can learn about the history and science of water treatment.

Handayama Botanical Garden: A Verdant Setting

The Handayama Water Distribution Site sits within Handayama Botanical Garden, a 110,000-square-meter hillside park established in 1964 on the grounds of the waterworks. The garden is home to approximately 3,200 plant species and 150,000 individual specimens, arranged by theme across the sun-drenched slopes. Cherry blossoms in spring, giant water lilies in summer, vivid autumn foliage, and camellias in winter ensure year-round appeal.

At the summit, the Ipponmatsu Kofun — a keyhole-shaped burial mound from the 5th century — offers panoramic views across Okayama city. The botanical garden is also a popular spot for night-time cherry blossom viewing in late March and early April, when the hillside is illuminated for evening visitors.

Nearby Attractions

Handayama is conveniently located in northern Okayama City, providing easy access to a range of cultural and leisure destinations. Okayama Korakuen, one of Japan's three most celebrated landscape gardens, lies approximately 2.7 kilometers to the south and can be reached in about 10 minutes by car. Adjacent to the garden stands Okayama Castle, known as "Crow Castle" for its striking black exterior. The Okayama Prefectural Museum is also nearby, offering exhibitions on regional history and art. For visitors arriving by rail, the JR Hōkaiin Station on the Tsuyama Line is a short walk from the botanical garden entrance, and Okayama Station — the major transportation hub for the region — is only one stop away.