Yonai Water Purification Plant Outlet Well

The Yonai Water Purification Plant Outlet Well

The Yonai Water Purification Plant Outlet Well (米内浄水場出水井, Yonai Jōsuijō Shussuisei) is an octagonal reinforced concrete well house of 1934 beside the main gate of the Yonai Water Purification Plant in Kamiyonai, Morioka City, Iwate Prefecture, listed as a Registered Tangible Cultural Property on 23 August 1999. Registered as No. 03-0018, it has a building area of 15 square meters.

Shussuisei literally means a well where water goes out, so the name appears to mark the outgoing side of the plant. The Agency for Cultural Affairs, however, says nothing about its function and describes only the architecture. Morioka City is not consistent either: its landscape listing calls it the outlet well house, while another city page describes the same octagonal building as a collecting well house (集水井上屋).

Design of the Yonai Water Purification Plant Outlet Well

According to the agency, the Yonai Water Purification Plant Outlet Well is a single-storey building on an octagonal plan, yet it is composed to read as two tiers from outside. The upper tier carries round windows in the same family as those of the filter bed control houses.

Oya stone appears here too, but used differently. On the outlet well it forms buttresses at the projecting corners and a band course running around the walls. Where the control houses use the stone to frame their base and openings, this building is outlined by its corner piers and horizontal bands, a deliberate variation on the same material.

Morioka City describes the design of this octagonal house as in the neoclassical, or Art Deco-like, manner popular at the time. The building was listed for contributing to the historic landscape of the country.

Looking at the Yonai Water Purification Plant Outlet Well

Start by following the octagon. At each corner of the Yonai Water Purification Plant Outlet Well an Oya stone buttress rises, and stone bands cross the walls between them. The bands split the walls into an upper and lower zone, and with round windows only in the upper zone the one-storey building reads as two.

Its place just inside the gate, on the left, makes it something like a gatekeeper. Compare it with the No. 3 control house on the right: both have round windows, but one is octagonal and banded, the other square and framed.

The city records that the house was repaired in 1985 and restored to its original drawings, and its landscape listing names it, with the memorial hall and the filter beds, among the structures that carry the plant's story from its opening.

Visiting the Yonai Water Purification Plant Outlet Well

The interior of the Yonai Water Purification Plant Outlet Well is closed. The plant grounds are normally off limits; the exterior can be seen during the spring cherry blossom opening and similar events.

Because it stands immediately to the left inside the gate, it is the first building you meet on entering. Kami-Yonai Station on the JR Yamada Line is about a 2-minute walk away. Follow staff directions on photography; drones are banned during the opening.