Related Clues:
- Electricity supply
- Distribution network seen in cockpit
- Water, gas or electricity supply
- Leader in Sun supporting principal source of power in the House
- Major conduits
- One island cutting another's power supply
- Major pipes
- Reservoir conduits
- Large water pipes
- Major water carriers
- Prodigious pipes
- Water or gas pipes
- Big conduits
- They may be accessed via manholes
- Major sewer lines