Risk assessment of long-distance water transmission pipeline based on fuzzy similarity evaluation approach

In order to ensure the normal operation of water supply projects, especially long-distance water transmission pipeline (LDWTP), it is necessary to recognize and avoid potential risk events during its operation process. As the vagueness and correlation of risk indices usually have a significant impact on the risk assessment result, those indices with high similarity are found out and eliminated based on the fuzzy similarity theory and triangular fuzzy number. Then the quantitative risk assessment using the fuzzy comprehensive evaluation method by combining analytic hierarchy process (AHP) approach is conducted based on the newly established risk index system. The case study shows that there are five groups of indices with high similarity and the risk index system can be screened from 27 indices to 22 indices. The risk assessment result illustrates that risk grades of the four categories from high to low are technology risk, management risk, third-party risk and nature risk. The comprehensive risk of LDWTP is high, which can help the decision makers to identify the most contributing risk events and allow them to take necessary measures for the risk reduction and risk control.