Suitability Analysis of Subsea Pipeline Route using GIS

• Main Author: Lee , Hui Yieng
• Format: Final Year Project
• Language: English
• Published: 2008
• Online Access: http://utpedia.utp.edu.my/2955/1/0001.pdf; http://utpedia.utp.edu.my/2955/
• Institution: Universiti Teknologi Petronas

The objective of this study is to analyze the least cost subsea pipeline route using GIS. A past project has been adopted in this research. The GIS-generated pipeline route is compared with the existing pipeline route designed using contemporary method. The subsea pipelines are used for hydrocarbon transportation from offshore platform to onshore plant. Criteria considered in least cost path are cost, pipeline routing criteria, installation method, safety and maintenance aspects. Factors affecting pipeline routing include bathymetry, submarine geographical features such as seabed conditions and slopes, obstructions such as coral reefs, wildlife preservation areas, as well as availability of existing services such as pipelines and platforms. Spatial Analyst extension in GIS is used to analyze all these factors through three basic steps and produce the best pipeline route through cost-weighted distance function. First step involves developing discrete cost surfaces in raster datasets from routing criteria datasets. Second step involves combining and weighing all discrete surfaces to create an accumulated cost surface. Third step involves developing least cost path between the source and destination along the accumulated cost surface. The result generated has shown similar alignment with the existing route. The GIS-generated route is 0.09km longer than the existing route. Although longer in length, the least cost route crosses less steep areas at length of three times more than the existing route. It crosses prawns' areas at 4% less than existing route as well. Therefore, the least cost path reduces the construction cost and increases the ease of construction as compared to the existing route. Hence, GIS-generated route satisfies the criteria of economical, least obstructions, safe and ease of construction in producing subsea pipeline route. Comparison between GIS method and contemporary pipeline routing method highlighted unique benefits of GIS that proved its feasibility in pipeline routing improvisation.