Evaluating Accessibility of High-Altitude Valleys

Abstract

The high-altitude mountain valleys of Calingasta, located in the province of San Juan, central western Argentina, along the border with Chile, are isolated and scarcely populated territories, rich in natural resources, scenic attractions, and grazing land. In spite of its economic potential, the development of the region has barely begun. A methodology is described that is designed to analyze accessibility to such valleys by roads located almost entirely in high mountain zones. A comprehensive study of regional resources was first developed, and the main sites of interest related to tourism, mining, and historical attractions were clearly identified. Alternative paths for the access roads were then traced following balanced criteria that considered not only the distance from the roads to sites of interest but also the real possibilities constrained by the complex topography of the area. In this study, maps, aerial photos, satellite images, and modern computational tools were used to define the alignments of the roads. Expeditions were also made to gather topographic data and information on soils, natural profiles, drainage patterns, and other terrain aspects, with intensive collection and use of Global Positioning System data. Afterward, different access alternatives were designed and their costs estimated, and life-cycle cost analysis was performed to select the most convenient ones. This study is a significant contribution to the long-delayed development of a vast region located in the southwest frontier in the province of San Juan.