The comprehensive pipeline (referred to as "common tunnel" in Japan and "common pipeline" in Taiwan, China) is a kind of underground urban pipeline complex corridor. It is a tunnel space constructed underground in the city, integrating various engineering pipelines such as electricity, communication, gas, heating, water supply and drainage, etc. It is equipped with dedicated inspection ports, hoisting ports and monitoring systems, and is planned, designed, constructed and managed uniformly. It is the "lifeline" of the important infrastructure that ensures the operation of the city.

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At present, only a few cities in China, such as Beijing, Shanghai, Shenzhen, Suzhou and Shenyang, have built comprehensive pipe galleries. According to incomplete statistics, the total construction mileage across the country is approximately 800 kilometers. The reason why comprehensive pipe galleries have not been widely promoted is not due to financial issues or technical problems, but rather due to issues related to awareness, laws, and conflicts of interests. 
So what are the main advantages of the combined pipe tunnel?
1. It reduces the frequency and number of road excavations, minimizing interference with urban traffic and residents' lives;
2. It can easily accommodate objects and be expanded in necessary periods, facilitating expansion;
3. It allows for inspections and checks within the common tunnel, making maintenance and management easier;
4. It has high structural safety, which is beneficial for urban disaster prevention;
5. Since the pipelines do not come into contact with the soil and groundwater, it avoids corrosion by acidic and alkaline substances, prolonging the service life;
6. It is beneficial to the urban landscape, reserving valuable space for planning and development needs;
7. For the management department of the pipelines in the common tunnel, the facility design, maintenance, management are easy, the safety is high, it is easy to coordinate with related units, and the procedures are simple.