GIS based modelling for forest road alignments, culvert placements and logging trail delineation
University of New Brunswick
Establishing stable forest road and trail networks requires proper trail and culvert placements. Past procedures involved manual surveying and hand digitizing road-stream crossings to estimate expected stream discharge for each location. This thesis reports on research-developed semi-automated ArcGIS/ArcMap tools to (i) align already digitized roads with DEM-recognized roadbeds, (ii) locate road-stream crossings and determine potential culvert locations and diameter, (iii) determine expected stream discharge and (iv) determine least-cost trail paths using DEM-generated cost rasters. Results show that hand-digitized roads veered off DEM roadbeds, sometimes by 20 meters or more. Similarly, mapped culvert locations do not always align with actual road-stream crossings. Also, existing culverts tend to accommodate 50 mm/day but not necessarily 100 mm/day discharge events, thereby leading to washouts. This thesis explores and demonstrates how the developed tools combined with the 1-m resolution LiDAR-DEM coverage for New Brunswick can bring road, culvert, and trail locations into better hydro-topographic alignments.