AbstractsGeography &GIS

Seasonal road design in mountainous terrain consists of four main phases: route selection, field investigation, surveying, and analysis. The first phase, route selection, consists of two parts: selecting control points at strategic locations, and then determining potential routes between those points. Two geographic information system (GIS) geoprocessing automations were developed to aid a road planner in determining routes between control points. Both automations utilized Environmental Systems Research Institute’s (ESRI) ArcGIS software package. The first method developed was the least cost path method, which makes use of ArcGIS’s cost path tool to find a route between points following a gradual slope. The second automation was the side hill method, which utilized a variety of ArcGIS tools to maintain a uniform grade along the side of a hill between two points. The two methods were compared and contrasted based on control point locations. The least cost path method was determined to be preferable for main thoroughfares along flat valleys and ridge lines, while the side hill method was preferable for secondary roads that could be used to access steeper ground. It was concluded that the two methods can save time and increase accuracy of GIS road features for land managers planning new seasonal roads.