Traditional construction method: the Saihiro Itabame Panel Dam

2. Major significance / Summary

The Saihiro Itabame Panel Dam is a wood frame weir 61m wide and 2.3m high built on the Yoro River
in Chiba Prefecture to supply irrigation water. It combines 4 members?Oyabashira, Kashira, Hikae,
Hotate, and scallops linked transversely by Hari. Its upstream surface is waterproofed by Uwaita,
Shitaita, Makura and Dohgi. When the water rises, the stiffeners at both ends are removed to instantly
overturn the dam, allowing the water stored upstream to discharge safely. This is a traditional
technology incorporating our ancestors’ wisdom and ingenuity,.

3. Keywords

Panel dam, wood frame weir, traditional technology, supplying irrigation water, weir opening

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II. Categories

4. Focus of this information

Transferable indigenous knowledge (TIK)

5. Users

5-1. Anticipated users: Community leaders (voluntary base) , Administrative officers

5-2. Other users:

6. Hazards focused

Flood

7. Elements at risk

Human lives , Rural areas

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III. Contact Information

8. Proposer(s) information (Writer of this template)

Goto Masahiro
Department of Rural Technologies, Research Team for Urban-Rural Interchange
griese@affrc.go.jp
TEL +81-29-838-7558

9. Country(ies)/region(s) where the technology/knowledge/practice originated

JAPAN/Ibaraki

National Institute for Rural Engineering

10. Names and institutions of technology/knowledge developers

National Institute for Rural Engineering

11. Title of relevant projects if any

12. References and publications

Technical Report of the National Institute for Rural Engineering No.204

13. Note on ownership if any

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IV. Background

14. Disaster events and/or societal circumstances, which became the driving force either for developing the technology/knowledge or enhancing its practice

It is a facility for taking water from a river, but equipped with a mechanism for safely discharging stored water during flooding, it is sure to be used in regions where flooding and droughts occur.

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V. Description

15. Feature and attribute

 

 

板羽目堰の断面概要図　Sectional view of Itabame weir

 

板羽目堰の平面概要図　Plane view of Itabame weir

 

胴木 = Dohgi

親柱 = Oyabashira

頭 = kashira

張 = hari

控 = hikae

帆立 = hotate

16. Necessary process to implement

 

張，親柱，控が左右岸方向に移動す Hari, Oyabashira, Hikae are moved to left - right bank direction

頭が親柱からはずれ，親柱が下流に傾 Kashira are shifted from newels so Oyabashira are inclined downstream

各部材がはずれる Members are shifted out of position.

17. Strength and limitations

18. Lessons learned through implementation if any

It is a traditional technology, so technology is needed to make the woodenmembers.

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VI. Resources required

19. Facilities and equipments required

Its members are made of wood so a nearby forest is needed. And because itis submerged, the wood must be very water resistant. To build a woodenframe weir on a river or canal, concrete work is needed as foundation workin order to install the wooden members on the riverbed.

 

20. Costs, organization, manpower, etc.

Precision woodworking is needed, but it is possible to make a duplicate of the Saihiro Itabame Panel Dam. It would cost several million yen.

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VII. Message from the proposer if any

21. Message

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VIII. Self evaluation in relation to applicability

22. How do you evaluate the technology/knowledge that you have proposed?

It is a technology/knowledge that has fair applicability demonstrated by implementation in one or more field sites.

23. Notes on the applicability if any

PR for traditional technology

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IX. Application examples

No.1

E1-1. Project name if available




E1-2. Place

JAPAN/Chiba prefecture




E1-3. Year




E1-4. Investor

government




E1-5. People involved




E1-6. Monetary costs incurred




E1-7. Total workload required




E1-8. Evidence of positive result

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X. Other related parallel initiatives if any

Message

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XI. Remarks for version upgrade

Message