The Infrastructure Division is made up of members employed in the construction and maintenance of a permanent way and associated structures such as signalling, buildings, bridges, electrical reticulation and related areas.
Each group within the Infrastructure Division are represented on the RTBU's Divisional Committee by members from the following areas:
- Metropolitan District Group: 4 Per Way, 1 Signal and 1 Electrical Representative
- Northern District Group: 1 Representative
- North Coast District Group: 1 Representative
- Western District Group: 1 Representative
- Southern District Group: 1 Representative