Abstract:Using Laoxiqiao Village in Yangshahu Town as an example, the MIKE model was used to analyze the health degree of a rainwater pipe network system in Xiangyin County of Yueyang City during rainstorm interference. The model was calibrated and validated using the measured water depth of severe waterlogging points during a rainfall process. Design rainfall with a duration of 2-hour and return periods of 1, 3, 5, 10, and 20 years was simulated, and the 3-year 2-hour rainfall process was studied in detail. A health evaluation index system for rainwater pipe networks considering four comprehensive indicators including drainage capacity, pipe network structure, environmental factors and social factors with 15 sub-indicators was constructed. The results show that the comprehensive scores for drainage capacity, pipe network structure, environmental factor and social factor are 0.48, 0.78, 1 and 0.66, respectively. The overall health degree is 0.54, indicating a poor comprehensive health level. The greater the recurrence period, the deeper the water depth, but the arrival time of the maximum water depth is not affected by the recurrence period. The locations with greater risk of waterlogging and deeper water are located near pipelines with lower health degree.