How to consider the water supply system in terms of water supply and drainage?

The system diagram is mainly viewed in combination with the plan view, and the corresponding parts can be found from the system diagram, the vertical direction, elevation and other information of the pipeline at this location can be seen, which cannot be done. represented by the plan view. In other words, the plan view is a top view, while the system diagram is a front view. Only the combination of plan view and system diagram can reflect a three-dimensional effect.