| Amagase Dam | |
| Location Map: | Japan |
| Coordinates: | 34.8808°N 135.8281°W |
| Country: | Japan |
| Location: | Uji, Kyoto |
| Status: | In use |
| Construction Began: | 1955 |
| Opening: | 1964 |
| Dam Type: | Arch, variable-radius |
| Dam Height: | 730NaN0 |
| Dam Length: | 2540NaN0 |
| Dam Volume: | 1620000NaN0 |
| Dam Crosses: | Uji River |
| Spillway Count: | 4 |
| Spillway Type: | Crest, controlled overflow |
| Spillway Capacity: | 6800NaN0 |
| Res Name: | Lake Hōō |
| Res Capacity Total: | 262800000NaN0 |
| Res Catchment: | 42000NaN0 |
| Res Surface: | 1.90NaN0 |
| Plant Operator: | Kansai Electric Power Company |
| Plant Capacity: | 92 MW (Amagase) 466 MW Kisenyama PS |
The is an arch dam on the Uji River just upstream from Uji, Kyoto Prefecture, Japan. The main purpose of the dam is flood control but it supports a hydroelectric power station and creates the lower reservoir for the Kisenyama Pumped Storage Plant. The dam itself serves a 92 MW power station while the pumped-storage power station upstream has a 466 MW capacity. Construction on the dam began in 1955 and it was complete in 1964. The pumped-storage power station became operational in 1970. Both plants are owned by Kansai Electric Power Company.
The dam is a 730NaN0 tall, 2540NaN0 long variable-radius arch type with structural volume of 1620000NaN0. The dam withholds a reservoir called of 262800000NaN0 of which 200000000NaN0 is active or "useful" storage. It has a surface area of 1.90NaN0.[1]
The dam's spillway consists of four 4.360NaN0 x 100NaN0 floodgates on its crest with a maximum discharge capacity of 6800NaN0. In the middle of the dam body, there are three 3.60NaN0 x 4.70NaN0 gate-controlled orifice openings with a maximum discharge of 11100NaN0. The dam's power station has a 92 MW installed capacity and a discharge capacity of 1860NaN0.[2]
Using Lake Hōō as the lower reservoir, water is pumped up to the upper reservoir via two pump-generators. The upper reservoir is created by a rock-fill dam that is 910NaN0 high, 2550NaN0 long and has a crest width of 110NaN0. The dam also has structural volume of 23380000NaN0 and withholds a reservoir of 72270000NaN0 of which 54080000NaN0 is active storage. From the upper reservoir, water can be released back down to the power station where the two 233 MW reversible Francis turbine pump-generators use it for power production.[1]
This process can be repeated and generation usually occurs during peak usage periods. The high water level at the upper reservoir is 2960NaN0 above sea level while it is 78.50NaN0 ASL in the lower reservoir. This affords the power station an effective hydraulic head of 219.350NaN0. Its discharge capacity is 2480NaN0. The first generator of the pumped-storage power station was operational in January 1970, and the second in July of that year. It has a maximum output of 466 MW.[1]