About the Tanukisawa No. 1 Stone Dam
The Shohoji River Tanukisawa No. 1 Stone Dam (正法寺川狸沢第一号石堰堤) is a stone erosion-control dam built in 1923 on the Tanukisawa, a tributary ravine of the Shohoji River in Shimo-Oginoto, Tendo City, Yamagata Prefecture, and was registered as a Registered Tangible Cultural Property in 2005.
The Tanukisawa joins the main stream from the right just above the Kitasawa No. 2 dam. The Shohoji River Tanukisawa No. 1 Stone Dam is the uppermost of its three dams: 7.0 metres along the crest and 2.4 metres high, a mortared gravity dam laid in the diagonal Tanizumi pattern, battered at 2 bu upstream and 3 bu downstream.
Why It Was Registered
The Agency for Cultural Affairs remarks that, small as it is, the dam was given the full kit of a serious structure: a secondary dam and bank revetments. The secondary dam is a low second wall below the main one that catches the overflow and keeps it from scouring the foot. Fitting that arrangement to a 7-metre dam shows the engineers took the tributary's sediment seriously.
A square drain hole pierces the lower centre of the dam, letting ordinary flow pass and keeping water pressure from building up behind the wall. The Shohoji River Tanukisawa No. 1 Stone Dam was registered as a structure that contributes to the historic landscape of the country.
What to Look For
From just downstream of the Shohoji River Tanukisawa No. 1 Stone Dam, you can see main dam, secondary dam and revetments working as a unit: all the parts of a large dam, scaled down to a narrow ravine.
Look for the square drain hole low in the centre of the face. Among the diagonal joints of the tanizumi, its straight-edged opening stands out.
Visiting the Tanukisawa No. 1 Stone Dam
The Shohoji River Tanukisawa No. 1 Stone Dam is an open-air river structure with no admission fee or opening hours. The face of the dam is best seen from the downstream bank; do not walk along the crest or climb down into the stream when the water is up. The Tanukisawa No. 2 dam is about 30 metres downstream.
Directions to the valley and safety notes are on the page for the Shohoji River Erosion Control Facilities.
- 📍 Plan Your Visit to Yamagata
- Find tours, activities & transport passes near Shohoji River Tanukisawa No. 1 Stone Dam
- [ Yamadera Temple & Zao Onsen Hot Springs ]
Q&A
- Where is the Shohoji River Tanukisawa No. 1 Stone Dam?
- It is on the Tanukisawa ravine of the Shohoji River in Shimo-Oginoto, Tendo City, Yamagata Prefecture. It is the uppermost dam on the Tanukisawa, the right-bank tributary that joins the main stream just above the Kitasawa No. 2 dam.
- When and why was the Shohoji River Tanukisawa No. 1 Stone Dam built?
- It was built in 1923 as part of the first phase of the Shohoji River erosion-control project, which Yamagata Prefecture undertook after the flood of 1913 to stop sediment washing downstream.
- What is the square hole in the Shohoji River Tanukisawa No. 1 Stone Dam for?
- It is a drain hole. Set low in the centre of the dam, it lets ordinary flow through so that water pressure does not build up behind the wall. The Tanukisawa No. 2 dam has the same feature.
- Can I see the Shohoji River Tanukisawa No. 1 Stone Dam up close?
- It is an open-air river structure with no admission fee or opening hours, and can be viewed from the bank. The face of the dam is best seen from the downstream bank; do not walk along the crest or climb down into the stream when the water is up.
- When did the Shohoji River Tanukisawa No. 1 Stone Dam become a Registered Tangible Cultural Property?
- It was registered on 12 July 2005 as a Registered Tangible Cultural Property (structure), as a structure that contributes to the historic landscape of the country.
Basic Information
| Name | Shohoji River Tanukisawa No. 1 Stone Dam |
|---|---|
| Location | Shimo-Oginoto, Tendo City, Yamagata Prefecture |
| Designation | Registered Tangible Cultural Property (structure), registration no. 06-0074 |
| Year Designated | Registered 2005/7/12 (Heisei 17) |
| Quantity | 1 dam |
| Dimensions | Crest length 7.0 metres, height 2.4 metres, with a secondary dam and bank revetments |
| Owner | Yamagata Prefecture |
| Public Access | Open-air river structure; no admission fee or set hours |
References
- Agency for Cultural Affairs, Database of National Cultural Properties: 正法寺川狸沢第一号石堰堤
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00004865
- Yamagata Prefecture: Shohoji River Erosion-Control Facilities, Registered Tangible Cultural Properties (PDF, Japanese)
- https://www.pref.yamagata.jp/documents/4123/syohozigawa.pdf
Last verified: 2026.09.24
