Case Studies

This case study evaluates the Inner Melbourne 30 km/h Speed Limit Trial, in which selected inner-suburban streets had their default 50 km/h limit reduced to 30 km/h for an initial trial period. The trial was a coordinated initiative between the City of Melbourne, the City of Yarra and the Department of Transport and Planning, and was designed to test how a lower urban speed limit performs against three objectives at once: reducing crash severity for vulnerable road users, supporting livability and amenity in mixed movement-and-place streets, and maintaining acceptable journey-time outcomes for through-movement traffic.

The evaluation captured before-and-after data on speed compliance, traffic volume, pedestrian and cyclist activity, crash frequency and severity, community sentiment, and business activity along the affected streets. Findings include strong speed compliance once supporting infrastructure (signs, pavement markings, kerb treatments) was in place, a measurable increase in pedestrian and cyclist activity, and broadly positive community response after an initial adjustment period. The case study draws out practical lessons on engagement, signing strategy, and the role of consistent default-limit policy at municipal-boundary edges; it is referenced in the Austroads Guide to Road Safety speed-management chapter and in subsequent jurisdictional speed-policy reviews.