The main lines and sidings at Diamond Valley, Nillumbik, Meadmore Junction and Pine Creek consist of 14lb/yd. flat-bottomed rail, laid to a gauge of 184 mm (7.25"). The sleepers consist of 75 mm x 50 mm x 500 mm long durable timber, laid flat and spaced approximately 300 mm apart. The completed track is ballasted with 16 mm screenings. The minimum curve radius is 18.2 meters (60') and the heaviest grade is 1 in 40 (2.5%).

New 6 kg/m rail. Photo B. Campbell

Since 2001 the mainline is being progressively re-laid with 6 kg/m (12 lb/yd) brand new flat bottomed rail on 65 mm x 65 mm x 477 mm long or 50 mm x 50 mm x 477 mm long, recycled plastic sleepers spaced approximately 250 mm apart.

The loading gauge is such that the absolute maximum allowable width of rolling stock is 680 mm (27"). The preferable maximum width is 560 mm (22"). The storage tracks in the carriage sheds are only 600 mm (24") apart and the entrances to the locomotive shed are only 1190 mm (3' 11") high. The minimum spacing between parallel sidings is nominally 900 mm (3'). The minimum spacing between parallel main lines is nominally 1200 mm (4'). All station platforms are nominally 150 mm (6") above rail level.

The only dual gauge (7.25/5 inch) siding is located in the wetlands area. Photo S. Daly