How often and what kind of inspection or maintenance do the sewer pipe?

For trunk lines and semi-trains (those with a pipe diameter that can be used by humans), a large amount of sewage flows at all times, making it difficult for sediments such as sludge to be generated. Regarding old and aging sewer pipes in the year, we are conducting surveys and inspections sequentially and repairs depending on the situation.

Branch lines (those with a pipe diameter that cannot enter) have little water flow and are easy to stay, so regular cleaning and inspections are carried out to maintain the flow function and repair abnormal areas.