| Dachaoshan Dam | |
| Location Map: | China |
| Coordinates: | 24.0244°N 100.3692°W |
| Country: | China |
| Location: | Yunnan Province |
| Status: | In use |
| Construction Began: | 1997 |
| Opening: | 2003 |
| Cost: | RMB¥8.87 billion ($1.3 billion USD) |
| Owner: | Yunnan Dachaoshan Hydropower Co., Ltd. |
| Dam Type: | Gravity, roller-compacted concrete |
| Dam Length: | 4600NaN0 |
| Dam Height: | 1110NaN0 |
| Dam Volume: | 11267000NaN0 |
| Dam Crosses: | Lancang (Mekong) River |
| Spillway Count: | 5 |
| Spillway Type: | Controlled, crest overflow |
| Res Name: | Dachaoshan Reservoir |
| Res Capacity Total: | 9400000000NaN0 |
| Res Catchment: | 1210000NaN0 |
| Plant Hydraulic Head: | 72.50NaN0 (rated) |
| Plant Commission: | 2001-2003 |
| Plant Turbines: | 6 x 225 MW |
| Plant Capacity: | 1,350 MW |
| Plant Annual Gen: | 5931 GWh |
The Dachaoshan Dam is a gravity dam on the Lancang (Mekong) River in Yunnan Province, China. The sole purpose of the dam is hydroelectric power production as it supplies water to a power station containing six 225 MW generators for a total installed capacity of 1,350 MW.
Initial construction preparations on the dam began in 1993 before it was approved ready for construction in 1994. On August 4, 1997, the project was approved for construction commencement and on November 10, 1997, the river was diverted. Between 2001 and 2003, the dam was complete and all six generators went operational.[1]
The dam is a 1110NaN0 tall and 4600NaN0 long gravity dam.[2] It is composed of 11267000NaN0 of concrete, 7566000NaN0 is roller-compacted concrete. The reservoir created by the dam has a capacity of 9400000000NaN0. To release water downstream, the dam has five 140NaN0 x 170NaN0 crest openings along with three mid-level openings and one bottom flushing outlet. With these openings, the design flood discharge capacity of the dam is 180000NaN0 while the maximum is 235000NaN0.[1]
The dam's power station is underground and supplied with water via six 179.50NaN0 long penstocks. Once through the six turbines, the water exits back to the river by means of two tailrace tunnels, one 13550NaN0 long and the other 12480NaN0.[1]