Risk-Based Evaluation of Trenching Methods in Pipeline Installation with Pre & Post-Lay Trench Approaches to Improve Time and Cost Performance

Purpose: This study aims to provide information about the risk factors involved in trenching work and its mitigation. An analysis of the risk ranking, the relationship between the risk factors frequency (independent) and the impact on time and cost performance (dependent), and a correlation model between the independent and dependent variables are presented here. It is hoped that identifying risk factors and how to control them can be a reference for maximising the performance of trenching projects in Indonesia. Design/methodology/approach: Literature reviews and case studies were conducted to identify and collect the risk factors associated with these trenching works. A questionnaire was developed for expert validation of the risk factors and to gather the opinions of 30 respondents related to the frequency and impact level using a Likert scale. The homogeneity test, validation and reliability data, risk correlation, and model regression were performed using SPSS v29. Risk ranking and risk control analysis were performed using the Risk Matrix and the Level 2 Risk Assessment form. Findings: Three risks - the X19 survey result, the X22 trenching equipment availability, and the X24 vessel selection-remain at a moderate risk level. The other risks are considered to be insignificant residual risks with the mitigation provided. Research limitations/implications: Due to the country's limited equipment availability, the trenching contractor in Indonesia may encounter X22 as a technical challenge. Therefore, further research is required to provide the equipment database, including the availability and capacities related to seabed conditions, soil strength and water depth. Originality/value: This study provides information and analysis on prominent or relevant risks for both pre and post-lay trenching works in Indonesia