For having more micromanagement (particular cute in little bases, but can be stressful in large system), we could have different "layer":
- Power: power line in classic underground pipes, pylons, maybe some differentation from
- Water: water pipes, Roman aqueducts
- Sewer System
- Resource Movement system: conveyor belts, underground or "flying"
For keep the system simple, every item on the list above, under the road. Player build the road, will have every thing underground done. If the building is connected to the road, good, if not... will be isolated, and the construction won't even start. :D