Shobojigawa Minamisawa Dam No. 5
Work in the Minamisawa ravine began here. Dam No. 5 is the uppermost structure of the second construction phase, started in 1926.
The Shobojigawa is a mountain tributary of the Kuratsugawa in the Mogami river system, running past Shimo-Oginoto in Tendo City. Following the flood of 1913, the prefecture placed stone dams and current-control works through the north, Tanuki and south branches of the valley between 1922 and 1927, this dam among them.
Standing in the upper reach of the Minamisawa, it opened the second phase of works carried out from 1926 to 1927. A small dam with a two-bu batter on both faces, built to ease the gradient of the stream bed.
Why It Matters
The Shobojigawa scheme sets sixteen dams along the north branch, three along the Tanuki ravine and ten along the south branch, together with wire-gabion current-control works. No single dam is large; instead they are strung from upstream to down, catching sediment stage by stage.
It is built by the tanizumi method, stones set diagonally so they interlock, a pattern that stands up well to moving water. The joints are packed with mortar, in the nerizumi manner, binding the body into a single mass. Both faces are given a 2-bu batter, a nearly upright lean of about one in 5.0.
In 2005 the Shobojigawa erosion-control facilities were placed on the national register of tangible cultural properties. The listing cites their contribution to the historical landscape of the country, recognising a modern civil-engineering work as heritage that shapes the character of a place.
Seeing It Today
The dam sits along a mountain stream, not at a developed sightseeing spot. Watch your footing, and stay away when the water is high. Look closely at the face of each set stone and the finish of the overflow lip, and the density of hand labour from before mechanisation comes into view.
The dam measures 15 metres along its crest and stands 3.0 metres high. It belongs to the Minamisawa branch and was completed in 1926.
- 📍 Plan Your Visit to Yamagata
- Find tours, activities & transport passes near Shohoji River Minamizawa No. 5 Stone Dam
- [ Yamadera Temple & Zao Onsen Hot Springs ]
Q&A
- What exactly is a stone check dam?
- It is a low masonry wall built across a mountain stream to trap gravel and sand and to slow the water, reducing the risk of debris flows downstream. These examples are made of dressed stone rather than concrete.
- Can I visit it, and is it free?
- The dams stand on public land along the stream and can be seen from outside at no charge, but there are no visitor facilities, signs or guardrails. Treat it as backcountry and go prepared.
- Are there dams above No. 5?
- In the Minamisawa, the registered structures run from No. 5 to No. 14. No. 5 marks the upstream end, and the others follow downstream from it.
- When were these dams built and listed?
- This one dates to 1926, part of works carried out between 1922 and 1927. The whole group was registered as a national tangible cultural property in 2005.
Basic Information
| Name | 正法寺川南沢第五号石堰堤 (Shobojigawa Minamisawa Dam No. 5) |
|---|---|
| Location | Shimo-Oginoto, Tendo City, Yamagata Prefecture |
| Designation | Registered Tangible Cultural Property (structure), registered 2005; registration no. 06-0079 |
| Date | 1926 (大正15年) |
| Form | Gravity-type stone check dam; crest length 15 m, height 3.0 m; 1 unit |
| Owner | Yamagata Prefecture |
| Access | Mountain stream; no visitor facilities. Open watercourse, viewable from public land. |
References
- National Database of Designated Cultural Properties, Agency for Cultural Affairs — 正法寺川南沢第五号石堰堤
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00004888
- Tendo City — Registered Tangible Cultural Properties
- https://www.city.tendo.yamagata.jp/tourism/history/tourokubunkazaihoka.html
- Cultural Heritage Online, National Institutes for Cultural Heritage — Yamagata / Tendo
- https://bunka.nii.ac.jp/heritages/region/6/6210
Last verified: 2026.07.03