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Visita Dominicana

Monción Dam

The Monción Dam is an earth-filled embankment dam on the Mao River near Monción in the Santiago Rodríguez province of the Dominican Republic. At 119 m high, it is the tallest dam in the country and in the Caribbean. The purpose of the dam is to produce hydroelectric power and supply water for irrigation.

It is an earthen structure with a clay core and a height of 119 meters, the highest of its kind in the country. It has multiple purposes: agricultural services, electricity production, human consumption, fishing and tourism. The filling of the reservoir began on September 22, 2001. This is considered the opening date.

The reservoir had already been inaugurated on May 28, 1998 and the hydroelectric plant on April 27, 2002. The total cost of the dam, including the reservoir, was RD$3,612,304,500; of which, 89% was contributed with the National Government’s own resources and the rest with international financing. The source of supply for this dam is the Mao River, a tributary of the Yaque del Norte, which supplies the reservoir of the Monción dam with a capacity of 370 million m3 of water.

Its maximum level of normal operation is 280 meters above sea level, the surface of the lake with the normal level of operation is 11 km2. The function of the dam is to retain the flows of the Mao River, including most of the extraordinary floods, for storage and use of water according to the needs of the different sectors.

The dam is equipped with an instrumentation system made up of thirteen piezometers, five piezometers-accelerographs, three inclinometers and three acentrimeters. The spillway is a free-flow type, with a maximum capacity of 5,750 m3/sec. It consists of an entrance channel at a height of 276.50 meters above sea level, with a width of 85 meters until reaching the bed, from which the cross section is variable. The material excavated from the dump was used to fill the dike.

The Monción Dam has a total of 5,637 meters of tunnels located on its left abutment, distributed as follows:

  • Diversion tunnel: served to divert the Mao River from its original channel to proceed with the placement of the fill of the dam.
  • Drainage tunnel: one of its functions is to lower the level of the reservoir in an emergency situation.
  • Pressure tunnel to the hydroelectric plant: leads the water to the power house, through the force of which it produces electrical energy.
  • Tunnel leading to the hydroelectric plant: it is a circular section with a simple concrete lining, for which 4,358.50 m3 were used.

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How to get to La Presa de Monción: CLICK HERE!