The value of a desk study for building a national river obstacle inventory

摘要

This study evaluates two desk-based approaches for building an inventory of man-made river obstacles. The creation of a river obstacle inventory is a vital first step in developing a prioritization process for obstacle removal and/or modification. In this study, a desktop geographical information system analysis of two rivers and their tributary network was undertaken, using two different approaches. The first involved analysing historical maps, satellite imagery, and Ordnance Survey Ireland Discovery Series maps and producing a geo-referenced layer of all the potential river obstacles. The second involved developing a geo-referenced layer of potential river obstacles based on the intersections between elements of the transport network (roads and railways) and river systems. To determine the effectiveness of the desk studies, the located obstacles were cross-referenced with actual obstacles verified through a field survey.