Rapel Dam

Rapel Dam
Location of Rapel Dam in Chile
Official name	Presa Rapel
Country	Chile
Location	La Estrella
Coordinates	34°02′29″S 71°35′19″W
Opening date	1968
Owner(s)	Endesa
Dam and spillways
Type of dam	Arch, variable radius
Impounds	Rapel River
Height	112 m (367 ft)
Length	350 m (1,148 ft)
Width (crest)	5.5 m (18 ft)
Width (base)	19 m (62 ft)
Spillway capacity	10,000 m3/s (353,147 cu ft/s)
Reservoir
Creates	Lake Rapel
Total capacity	700,000,000 m3 (567,499 acre⋅ft)
Active capacity	530,000,000 m3 (429,678 acre⋅ft)
Power Station
Commission date	1968 (1968)
Hydraulic head	76 m (249 ft) (net)
Turbines	5 x 75.4 MW Francis-type
Installed capacity	377 MW

The Rapel Dam is an arch dam on the Rapel River about 19 km (12 mi) north of La Estrella in the Libertador General Bernardo O'Higgins Region, Chile. The primary purpose of the dam is hydroelectric power generation and it supports a 377 MW power station. The dam was completed in 1968 and is owned by Endesa. It creates the largest reservoir in Chile with a capacity of 700,000,000 m³ (567,499 acre⋅ft). The dam withstood the 7.5 M_w 1985 Rapel Lake earthquake with only minor damage. It was centered 45 km (28 mi) from the dam.

Design

The Rapel Dam is a 112-metre (367 ft) tall and 350-metre (1,150 ft) long variable-radius arch-type. It is 5.5 metres (18 ft) wide at its crest and 19 metres (62 ft) wide at its base. The dam's spillway is controlled by five tainter gates and has a discharge capacity of 10,000 cubic metres per second (350,000 cu ft/s). The dam's reservoir, Lake Rapel has a 700,000,000 cubic metres (570,000 acre⋅ft) capacity of which 530 million cubic metres (430,000 acre⋅ft) is active capacity.

Power station

The power station, located at the dam's base, contains five 75.4 megawatts (101,100 hp) Francis turbine-generators and is afforded 76 metres (249 ft) of net hydraulic head.