Abstracts

Examination and Selection of an Optimal Digital Elevation Model for CFB Gagetown

Officially opened in 1958, Canadian Forces Base (CFB) Gagetown, covers 1100 km2 and is located 20 km. from the City of Fredericton. The terrain of the training area is well suited to all types of training. Unfortunately, extensive use of vehicles in manoeuvre areas combined with poor drainage has resulted in serious erosion concerns. Extensive environmental efforts are in progress throughout the training area in order to reduce the amount of sedimentation in fragile riparian ecosystems. Although well intended, theses small projects requires massive planning, control and validation. Since the access to the training area is highly restricted, it becomes clear that changes should be made to improve the efficiency of erosion control projects. An accurate Digital Elevation Model (DEM) is a central requirement of all projects underway; it helps to directly locate and monitor streams, slopes and watersheds. Indirectly, it enables the production of orthophoto maps, intervisibility analyses, and three-dimensional visualisation. In this presentation the author will discuss the specifications of an optimal DEM product in order to meet CFB Gagetown's needs. Specifications have been produced from research conclusions and organised in a set of recommendations. Three different DEM's have been compared and assessed:
1. The existing DEM from 3rd Area Support Group (Originate from Service New Brunswick (SNB) with 1:35,000 scale aerial photography);
2. Light Detection and Ranging (LIDAR) data;
3. DEM produced from Applanix Digital Sensor System imagery. In order to be assessed as optimal, the DEM needs to be rapidly available and affordable (cost efficiency).