It is important to earthquake-proof infrastructure facilities in preparation for the occurrence of large-scale disasters. Minimizing damage caused by earthquakes and restoring functions as soon as possible will greatly contribute to the early restoration of the lives of residents. In this paper, we attempted a method to evaluate its sewerage system functions using the resilience triangle. This method enables to evaluate the resilience of a sewerage system by improving its resilience through the implementation of earthquake countermeasures and by evaluating the resilience of different restoration procedures. Furthermore, the results of this resilience evaluation and restoration procedures were visualized by configuring each element in PLATEAU, a 3D urban model developed by the Ministry of Land, Infrastructure, Transport, and Tourism （MLIT）. Studying restoration procedures and visualization enable easy-to-understand explanations of the restoration status not only to project operators but also to residents, leading to better understanding of the restoration plan and improved services for residents.

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The government provides support for rebuilding deteriorated span-unit pipes on the premise that they are properly maintained. For deteriorated pipes that are not eligible for support, local governments use construction and improvement funds to rebuild them, and use their own funds to repair them in an effort to reduce pipe defects. According to sewerage statistics, the percentage of renovations is increasing year by year due to national support, but repairs are covered by local governments at their own expense, and the percentage of repairs is decreasing due to financial problems and an increase in the amount of maintenancing. In this paper, the degree of abnormality in spans and the effect of repairs are shown by using a reliability curve to show the abnormality in span units based on the number of abnormal pipes in the span of pipes surveyed by TV cameras, and by showing the effects of repairs using reliability curves. express. The repairs in this paper assume partial replacement as defined in the sewerage maintenance management guidelines.

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In order to ensure early restoration in the event of an earthquake, priority needs to be given to inspecting sewer pipes that are vulnerable to damage. It is also necessary to identify sewer pipes susceptible to damage in order to formulate an effective sewer pipe seismic reinforcement plan. Damage rates were calculated for each sewer pipe characteristic, and the characteristics of sewer pipes susceptible to damage during an earthquake were analyzed.

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