Kannagawa Headrace Tunnel
| Orderer | Tokyo Electric Power Company Holdings, Incorporated |
|---|---|
| Completion | 2005 |
| Structure and scale | Headrace tunnel (NATM, minimum ventilation, rubber-tired system tunneling method): excavation cross-section: 79m², tunnel length 2,421m; headrace lower opening service tunnel: excavation cross-section: 28m², tunnel length: 360m; pressure-control tank: vertical shaft depth: 101.4m, finishing diameter: φ17m; connection road: light area: 821.5m, tunnel part: 678m; excavated soil treatment site: embankment volume: 564,000m³; concrete manufacturing and supply: shipping volume: 141,000m³ |
| Location | Gunma Prefecture |
| Application | Hydroelectric power station (water pumping type) |
The Kannagawa Hydropower Plant is a large-scale pure water pumping-type power station that spans across Nagano Prefecture and Gunma Prefecture. Every second, 510t of water flows through a headrace tunnel with an effective head of 653m, and the plant boasts an output of 470 thousand kW per unit.