A Process Using Risk Analysis to Select Construction Methods for Pipeline Crossings of Major Rivers

Pipeline river crossings pose a significant challenge for pipeline owners and environmental regulators to balance the associated costs and risks, particularly where environmental impacts may occur. For years, NOVA Gas Transmission Ltd. (NGTL) has managed the regulatory approval process using a well-established process. However, regulatory expectations are increasingly neutral to the cost of crossing installations and are demanding a more thorough assessment of a wider variety of river crossing options, particularly trenchless technologies. As a result, NGTL has recently enhanced the internal process by incorporating a structured decision tool. This tool is able to quantitatively assess technical risks as well as ‘soft’ influences such as “Regulatory Relationship” and “Delay in Approval”. The result is a clear decision with the necessary buy-in, where all risks were identified quantitatively and well understood by decision makers.