What Aoshita No. 1 Dam Intake Tower Is
Aoshita No. 1 Dam Intake Tower (青下第１ダム取水塔) is a reinforced concrete tower standing in the first Aoshita reservoir at Kumagane, Aoba Ward, Sendai City, Miyagi Prefecture, built in 1933 and listed as a Registered Tangible Cultural Property (Structures) on 7 June 1999. It rises 15.5 m and measures 2.4 m across on the inside. Free-standing in the water near the left bank on the upstream side, it meets the maintenance bridge over the dam crest at its top.
If the dam is a device for holding water, Aoshita No. 1 Dam Intake Tower is a device for choosing it. Three intake mouths open through the wall at upper, middle and lower levels, and operators open whichever draws the cleanest water at that moment. The surface layer clouds after rain; the layer near the bed runs cold and stirs up sediment. The designers assumed that water changes with depth, and gave themselves three options rather than one.
Water taken in descends inside the shaft to a gauging basin on the left bank below the main barrage, enters the conduit tunnel there, and travels to the Nakahara Purification Plant, which opened in 1923 and is the oldest in the city. The tower is where the whole chain of Sendai's first waterworks expansion begins.
Why It Carries a Listing
The criterion applied is contribution to the historic landscape of the nation. As architecture the tower is a plain cylinder with almost no ornament, yet a pale vertical shaft standing out of still water changes how the whole valley reads. The horizontal line of the barrage, the vertical of the tower, the thin bridge crossing between them: three elements meeting at right angles, which is very much how engineers of the early Shōwa era composed their structures.
There is a practical case as well. Building the intake as a separate tower rather than burying it in the dam body means inspection and repair do not depend on drawing the reservoir down. Ninety years of continuous service owe something to that decision. Reinforced concrete was itself a forward choice for municipal civil works in a provincial city at the time.
Of the eight structures registered here on the same day, only this tower and the Aoshita Dam Monument are classed as other constructed works rather than barrages or buildings. Neither dam nor architecture, the tower is a piece of pure water-handling equipment that happens to be beautiful.
What to Look For
To take in the whole shaft, look up from the downstream side of the barrage. The part above water alone stands several times human height, and the circular outline reads sharply against the sky. Its top is set level with the girders of the Aoshita Bridge, so walking across brings the crown of the tower to about waist height.
Lean over the rail and you can see the hatch through which workers descend inside to open and close the intakes. On a windless day the reflection holds its edges completely, and Aoshita No. 1 Dam Intake Tower appears to stand twice, once in air and once in water.
Directly beneath the tower lies the deepest part of the reservoir, which is why the water there sits darker than the rest. The colour shifts between indigo and green with the season and the light. Standing on the bridge and guessing which of the three mouths is open that day is a reminder that this is working equipment, not a monument.
Visiting Aoshita No. 1 Dam Intake Tower
The tower sits inside the Aoshita water source grounds and can be seen from the Aoshita Bridge or the paths around the barrage. The grounds admit visitors from 9:30 a.m. to 4 p.m. The interior is closed because the intake remains in service, and no special opening is held.
The closest approach is midway across the bridge. Follow the 500 m round-trip history path from the Aoshita Dam Former Management Office and the barrage appears at the bottom of the slope, about 5 minutes each way. Paths are unpaved and turn soft after rain. An attendant-operated electric wheelchair is kept at the Sendai City Waterworks Memorial Hall for use on the level stretches; there is one unit and reservations take priority, so ring ahead.
Nothing on site restricts photography. Shooting from the paths or the bridge is fine. For tripod work or commercial shoots, check first with the Memorial Hall on 022-393-2188.
Getting there: a Sendai City bus bound for Jōgi from Sendai Station, alight at Ōtemon-iriguchi, then 8 minutes on foot. From Kumagane Station on the JR Senzan Line it is 20 minutes on foot. Driving takes about 40 minutes from Sendai Station or about 30 minutes from the Sendai-Miyagi interchange. The Memorial Hall shuts from 1 December to 31 March.
- 📍 Plan Your Visit to Miyagi
- Find tours, activities & transport passes near Aoshita No. 1 Dam Intake Tower
- [ Matsushima Bay Cruise & Sendai Food Tours ]
Q&A
- Can I go inside Aoshita No. 1 Dam Intake Tower?
- No. The tower is still part of the working water supply and its interior is closed. You can see the exterior at close range from the Aoshita Bridge and from the paths around the dam.
- How tall is Aoshita No. 1 Dam Intake Tower?
- The register records a reinforced concrete structure 15.5 m high, with an internal diameter of 2.4 m, which is wide enough for an adult to work inside.
- Why does Aoshita No. 1 Dam Intake Tower have three intake openings?
- Water quality varies with depth in the reservoir. Upper, middle and lower intake pipes let operators open whichever level is drawing the cleanest water on a given day.
- Where does the water from Aoshita No. 1 Dam Intake Tower go?
- It runs to a gauging basin on the left bank below the main barrage, then through the conduit tunnel to the Nakahara Purification Plant, and finally to taps in part of central Sendai.
- What are the access and opening hours for Aoshita No. 1 Dam Intake Tower?
- Take the Sendai City bus for Jōgi, alight at Ōtemon-iriguchi and walk 8 minutes, or walk 20 minutes from Kumagane Station. The grounds open from 9:30 a.m. to 4 p.m. and entry is free.
Basic Information
| Name | Aoshita No. 1 Dam Intake Tower (青下第１ダム取水塔, Aoshita Dai-ichi Damu Shusuitō) |
|---|---|
| Location | 17-2 Oharamichi, Kumagane, Aoba Ward, Sendai City, Miyagi Prefecture |
| Designation | Registered Tangible Cultural Property (Structures) |
| Year Designated | Registered on 7 June 1999 |
| Quantity | 1 unit |
| Dimensions | Reinforced concrete, 15.5 m high, internal diameter 2.4 m |
| Owner | Sendai City Water Supply Business Manager |
| Public Access | Exterior viewing only, 9:30 a.m. to 4 p.m., free of charge. Interior closed |
References
- Agency for Cultural Affairs, National Cultural Properties Database: Aoshita No. 1 Dam Intake Tower
- https://kunishitei.bunka.go.jp/heritage/detail/101/00001087
- Sendai City Waterworks Bureau: Aoshita Water Source Walking Map
- https://www.suidou.city.sendai.jp/soshiki/somu-eigyo/koho/7/405.html
- Sendai City Waterworks Bureau: Visitor Information for the Aoshita Water Source Area and Memorial Hall
- https://www.suidou.city.sendai.jp/soshiki/somu-eigyo/koho/7/403.html
- Sendai City Waterworks Bureau: Purification Plants and Other Principal Facilities
- https://www.suidou.city.sendai.jp/jigyo/suigen-shisetsu-suishistsu/syuyoshisetsu/626.html
- Sendai City Waterworks Bureau: Electric Wheelchair for the Aoshita Water Source Paths
- https://www.suidou.city.sendai.jp/soshiki/somu-eigyo/koho/7/406.html
Last verified: 2026.09.08