A Small Pavilion beside the Pump House
The Former Nakajima Water Purification Plant Monitoring Room Building (旧中島浄水場監視室棟) is the monitoring room of a water purification plant of 1927 in Suidocho, Nagaoka City, Niigata Prefecture, and was registered as a Registered Tangible Cultural Property (structure) on December 24, 2013 (Agency for Cultural Affairs). In romanised Japanese it is Kyū Nakajima Jōsuijō Kanshishitsu-tō.
The Agency records a single-storey reinforced concrete building on a roughly square plan, with a flat roof and a building area of 57 square metres; registration number 15-0383.
The Former Nakajima Water Purification Plant Monitoring Room Building stands south-west of the pump room (Agency for Cultural Affairs). It is the smallest of the three registered buildings, set close beside the main pump house.
An Arch on Every Side
On each of its four sides, the Former Nakajima Water Purification Plant Monitoring Room Building raises a Parapet shaped like a semicircular arch at the centre (Agency for Cultural Affairs). The wall around each arch is finished in doitsu-kabe, the rough-textured render known in Japan as “German wall,” which sharpens the outline of the curve.
The base is clad in stone, and the walls carry pilasters scored with joints so that the concrete reads as masonry (Agency for Cultural Affairs). Rather than having a single front, the little building gives every side the same composition.
Why It Was Registered
The Agency for Cultural Affairs registered the Former Nakajima Water Purification Plant Monitoring Room Building as a model of design. Its description notes that the stone-like exterior was made to sit in harmony with the pump room.
With a building area of only 57 square metres, it still uses the same vocabulary as the main building on all four sides: arched parapets, a stone base and pilasters. It was registered in 2013 with the pump room and the standby generator room.
What to Look For
Compare the coarse texture of the render around the arches with the flat, jointed surfaces of the pilasters and the stone base. In low morning or evening light the rough render casts tiny shadows and the arches stand out.
Seen together with the pump room to the north-east, the matching arched parapets and stone bases are easy to pick out (Agency for Cultural Affairs). The Former Nakajima Water Purification Plant Monitoring Room Building reads like a miniature of the main building.
Visiting
The Former Nakajima Water Purification Plant Monitoring Room Building is in Suido Park, south-west of the pump room, and its exterior can be viewed from the park. Because all four sides share the same design, it is worth looking at it from more than one angle. No official information was found on interior access or photography rules (checked November 2026).
Q&A
- When was the Former Nakajima Water Purification Plant Monitoring Room Building built?
- In 1927 (Agency for Cultural Affairs), the same year as the pump room and the standby generator room.
- What is special about the Former Nakajima Water Purification Plant monitoring room?
- Each of its four sides has a semicircular arched parapet framed by rough “German wall” render, above a stone base and pilasters scored to look like masonry (Agency for Cultural Affairs).
- How big is the Former Nakajima Water Purification Plant monitoring room?
- It is a single-storey reinforced concrete building with a building area of 57 square metres (Agency for Cultural Affairs).
- Can you go inside the Former Nakajima Water Purification Plant monitoring room?
- No official information on interior access was found. The exterior can be seen from Suido Park.
- When was the Former Nakajima Water Purification Plant Monitoring Room Building registered?
- On December 24, 2013 (Agency for Cultural Affairs).
Basic Information
| Name | Former Nakajima Water Purification Plant Monitoring Room Building (旧中島浄水場監視室棟) |
|---|---|
| Location | 3-247-2 Suidocho, Nagaoka City, Niigata Prefecture |
| Designation | Registered Tangible Cultural Property (Structure) |
| Year Designated | Registered 2013/12/24 (Heisei 25) |
| Quantity | 1 building |
| Dimensions | Reinforced concrete, single storey, building area 57 m² |
| Owner | Nagaoka City |
| Public Access | Exterior visible from Suido Park; no official information on interior access |
References
- Former Nakajima Water Purification Plant Monitoring Room Building (Database of National Cultural Properties, Agency for Cultural Affairs)
- https://kunishitei.bunka.go.jp/heritage/detail/101/00009746
- Nagaoka Waterworks, FY2022 edition (Nagaoka City Waterworks Bureau, Japanese)
- https://www.city.nagaoka.niigata.jp/suidou/doc/suidou/w-s_summary/summary-r04.pdf
- Suido Park (Niigata Prefecture Tourism Association, Japanese)
- https://niigata-kankou.or.jp/spot/detail_43801.html
Last verified: 2026.11.14
