The Challenge of Crossing the Andes: A Data Base Analysis and Peru LNG Project Description

As of the date this paper is written pipelines in South America comprises 113000 kms of transmission lines including Oil, Gas, Condensates, and refined products from which approximately 17% (19400 kms) crosses the Andes reaching elevations up to near 5000mts. Rugged terrain combined with the geology, weather conditions (especially rain intensity) and continuous pipe ruptures in the past impose serious challenges for the pipeline industry that makes the design, construction and operation substantially different from other pipelines in the world. The records have shown that the threat of Ground movement/weather-related pipeline ruptures in the Andes plays a significant role since the percentage of the risk associated with geotechnical causes is substantially higher than any other parts such as Europe or United States. Thus the rate of pipeline failures due to natural forces is significant higher than the average industry. Peru LNG is a 406km × 34in gas pipeline transporting natural gas from the jungle side of Peru to the Pacific Coast where a LNG terminal has been installed. Peru LNG’s pipeline currently holds the record of being the highest Gas Pipeline of the world with a maximum elevation of 4901 meters above sea level. Project completion was done in May 2010 and lessons learnt from similar projects were taken into account since project designs. This paper is divided in two parts. First, it compares pipeline ruptures frequencies due to natural forces in the Andes with other pipelines in different terrains based on historical cases compiled by the authors. Secondly, it explains the different phases of Pipeline Project in rugged terrain from the conceptual design until the operations stage and the role of Pipeline Geotechnical Engineers in this process based on PERU LNG’s pipeline experience. It also describes some of the main features of the PLNG pipeline project. A comprehensive flow chart provides general guidance for future pipeline projects in similar conditions.