The Matsuno Dam is a multi-purpose concrete gravity dam located in Shimanto, Kochi Prefecture, Japan. It is situated on the Hiwatashi River, a tributary of the Shimanto River, one of Japan's last major free-flowing rivers often referred to as "Japan's Last Clear Stream."
Location: The Matsuno Dam is located in the northern part of Shimanto City, within Kochi Prefecture, on the island of Shikoku, Japan. Its precise geographical coordinates place it within a mountainous region, contributing to the natural beauty of the area.
Construction and Purpose: Construction of the Matsuno Dam commenced in the 1950s and was completed in 1960. The dam was primarily built to serve multiple critical functions for the region. Its main objectives include:
- Flood Control: Mitigating flood risks for communities and agricultural lands situated downstream along the Hiwatashi River and the main Shimanto River.
- Irrigation: Providing a stable water supply for agricultural purposes, supporting rice paddies and other cultivation in the surrounding fertile areas.
- Water Supply: Contributing to the general water supply for local communities, though its primary focus remains flood control and agriculture.
Technical Details:
- Type: Concrete gravity dam
- Height: Approximately 43.5 meters (143 feet)
- Crest Length: Approximately 145 meters (476 feet)
- Catchment Area: Approximately 43.8 square kilometers (16.9 sq mi)
- Reservoir Capacity: Approximately 2.8 million cubic meters (usable capacity)
- River: Hiwatashi River (a major tributary of the Shimanto River)
- Completion Year: 1960
Significance: Matsuno Dam is an important component of the water resource management infrastructure in the Shimanto River basin. While the Shimanto River itself is renowned for its largely undammed main course, dams like Matsuno Dam on its tributaries play a vital role in balancing ecological preservation with the practical needs of flood mitigation and agricultural productivity for the local population. It represents a key effort in regional development and disaster prevention that has benefited the communities along the Hiwatashi River for decades.