Projecto Trasvase Olmos

Location: Huancabamba River, Peru

Dates: 2007

The Olmos project is a hydroelectric and irrigation project currently being carried out by The Regional Government of Lambayeque Peru. The project includes construction of a concrete-faced rockfill dam, the Limón Dam, located in the Peruvian Andes on the Huancabamba River. The current as-built height of the dam is 43m and the Regional Government of Lambayeque plans to operate the dam at its current elevation for approximately 15 years. At that time, the dam will be raised to a final height of 85m.

The purpose of the dam is to create a reservoir for the diversion of water through a 19km long conveyance tunnel. The tunnel will carry water from the east side of the Andes to the west providing irrigation, and in future hydroelectric power, for towns located on the Peruvian Pacific coast. To enable the construction of the dam spillway, there have been major excavations in the rock outcrops located north and east of the spillway. The rock is of variable quality and has been hydrothermally altered and displaced with faults (likely extensional) that strike obliquely to the face of the rock excavation.

There have been two rock slide events in September 2006 and March 2007. Because of concerns with the long term stability of the rock slope, the Contractor commissioned GCG to investigate the cause of the failures and provide recommendations regarding the long term stability of the North-South slope.


Valstad, T., Cabarkapa, Z. & Tinto, W. (2008). Rock slide in spillway cut at Projecto Trasvase Olmos, Peru, Int. Geological Congress, Oslo, Norway.