<b>RISKS IN WASTEWATER PIPE INSTALLATION BY TRENCHLESS CONSTRUCTION METHOD PIPE JACKING FOR QUALITY PERFORMANCE IMPROVEMENT</b>

Trenchless construction is now the preferred method of installing underground city utilities, which is highly recommended. Using this trenchless technology can reduce the environmental impact significantly, minimize disturbance in surrounding area and provide shorter duration by using this construction method. Installation of wastewater pipes using the trenchless method is carried out underground and not visible from surface, so it requires a high level of precision. The purpose of this research is to identify construction risks and provide its response to improve the quality of project. The research employs a quantitative approach incorporating surveys, literature review, and case studies, with data analysis conducted using the Delphi method, while risk analysis is carried out using the Matrix Probability Index (MPI). The result of study shows six significant risks. Five of these are influenced by conformance to specification which leads to inaccurate survey and layout, change of soil condition based on environmental factors, diaphragm wall construction issues, mislead of laser causing misalignment, an obstacle that prevents progress of jacking works, while the other one influenced by technical skills of personnel which lead to inaccurate survey and layout risk. Early identification of significant risks in a project will ultimately contribute to the improved project quality performance.