Manhole: Vertical shafts constructed at regular intervals along underground pipeline locations. Primarily used for pipeline maintenance, sludge removal, and connecting pipelines of different directions and heights. Specific types include flushing manholes, street manholes, water distribution manholes, and wastewater manholes. Manholes are designed for the convenience of maintaining urban underground infrastructure, such as power supply, water supply, drainage, sewage, communication, cable TV, gas pipelines, and street lighting lines.
Generally located at pipeline intersections, bends, changes in pipe diameter or slope, and at regular intervals along straight pipe sections, these are convenient for periodic inspections of ancillary structures. Rainwater wells, with holes on their sides connected to drainage pipes, and a bottom with downward-sloping permeable pipes, can replenish rainwater underground and divert excess rainwater through the drainage pipes.