Porce III Dam
Encyclopedia
The Porce III Dam is an embankment dam
on the Porce River 90 km (56 mi) northeast of Medillin in Antioquia Department
, Colombia
. The dam was constructed between 2004 and 2011 for the primary purpose of hydroelectric power generation.
is a chute-type and is located on its left side. It is controlled by four radial gates and has a maximum discharge of 10850 m3/s. The reservoir
created by the dam has a 170000000 cubic metre capacity of which 127000000 cubic metre is active (or "useful") capacity. The reservoir has a surface area of 4.6 km² (2 sq mi). The catchment area
for the dam and reservoir is 3756 km² (1,450 sq mi). A submerged intake on the reservoir's left bank conducts water to the power station initially via a 12 m (39 ft) long and 10.2 m (33 ft) diameter upper headrace tunnel. At the terminus of this short tunnel, the water drops 149 m (489 ft) vertical shaft to the lower headrace tunnel which has the same diameter of the upper but is 304 m (997 ft) long. At the end of the lower headrace, it converts into four penstock
s to supply each of the underground power house's 172 MW Francis turbine
s with water. Once ejected from the power plant, it enters over 1000 m (3,281 ft) of tailrace tunneling and is returned to the Porce River.
Embankment dam
An embankment dam is a massive artificial water barrier. It is typically created by the emplacement and compaction of a complex semi-plastic mound of various compositions of soil, sand, clay and/or rock. It has a semi-permanent waterproof natural covering for its surface, and a dense, waterproof...
on the Porce River 90 km (56 mi) northeast of Medillin in Antioquia Department
Antioquia Department
Antioquia is one of the 32 departments of Colombia, located in the central northwestern part of Colombia with a narrow section that borders the Caribbean Sea. Most of its territory is mountainous with some valleys, much of which is part of the Andes mountain range...
, Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
. The dam was constructed between 2004 and 2011 for the primary purpose of hydroelectric power generation.
Background
Between 1974 and 1976, hydrological studies were carried out on the Porce River and between 1982 and 1983, studies regarding the river's hydroelectric development were completed. The study recommended the five projects, Porce I, Porce II, Porce III, Porce IV and Ermitaño. In December 1984, the feasibility report for Porce III was submitted and complementary studies were carried out between 1986 and 1996. In 2002, the design and consultancy contracts were awarded along with the environmental license issued. In 2004, construction on the dam began and the river was diverted by 2007. By 2010, the dam began to impound the reservoir and was complete by 2010. Between 2010 and 2011, all four generators were commissioned as well.Design and operation
The Porce III Dam is a 151 m (495 ft) tall and 426 m (1,398 ft) long concrete-face rock-fill type embankment dam. Its base width is about 400 m (1,312 ft) and it has a fill volume of 4155000 m³ (5,434,535 cu yd). The dam's spillwaySpillway
A spillway is a structure used to provide the controlled release of flows from a dam or levee into a downstream area, typically being the river that was dammed. In the UK they may be known as overflow channels. Spillways release floods so that the water does not overtop and damage or even destroy...
is a chute-type and is located on its left side. It is controlled by four radial gates and has a maximum discharge of 10850 m3/s. The reservoir
Reservoir
A reservoir , artificial lake or dam is used to store water.Reservoirs may be created in river valleys by the construction of a dam or may be built by excavation in the ground or by conventional construction techniques such as brickwork or cast concrete.The term reservoir may also be used to...
created by the dam has a 170000000 cubic metre capacity of which 127000000 cubic metre is active (or "useful") capacity. The reservoir has a surface area of 4.6 km² (2 sq mi). The catchment area
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
for the dam and reservoir is 3756 km² (1,450 sq mi). A submerged intake on the reservoir's left bank conducts water to the power station initially via a 12 m (39 ft) long and 10.2 m (33 ft) diameter upper headrace tunnel. At the terminus of this short tunnel, the water drops 149 m (489 ft) vertical shaft to the lower headrace tunnel which has the same diameter of the upper but is 304 m (997 ft) long. At the end of the lower headrace, it converts into four penstock
Penstock
A penstock is a sluice or gate or intake structure that controls water flow, or an enclosed pipe that delivers water to hydraulic turbines and sewerage systems. It is a term that has been inherited from the technology of wooden watermills....
s to supply each of the underground power house's 172 MW Francis turbine
Francis turbine
The Francis turbine is a type of water turbine that was developed by James B. Francis in Lowell, Massachusetts. It is an inward-flow reaction turbine that combines radial and axial flow concepts....
s with water. Once ejected from the power plant, it enters over 1000 m (3,281 ft) of tailrace tunneling and is returned to the Porce River.