#72 Local Street Management (pt 9) - Device Selection

The ninth entry in the current series on Local Area Traffic Management (LATM), as informed by the AGTM Part 8: Local Street Management [1], summarises Section 8 of the Austroads Guide, covering the selection of LATM devices. Subsections in the Guide describe four main groups of devices, including:

• Vertical deflection devices

• Horizontal deflection devices

• Diversion devices

• Signs, linemarking and other treatments

Device types and uses

Austroads lists the devices in the above groups against five specific uses or purposes. The uses include speed reduction, traffic volume reduction, crash risk reduction, pedestrian safety increase, and bicycle safety increase. 20 of the 27 listed measures (74%) have crash risk reduction as a stated use, while 19 (70%) are used to reduce traffic speeds. Table 1 below is reproduced from the Austroads Guide to show the relationships between listed treatments and their various purposes.

The Guide also provides an indication of the most and least commonly used devices in Australia and New Zealand according to local government authorities. The 20 measures most used in descending order include:

The Guide then describes the treatments in some detail in terms of their application, advantages and disadvantages. Additional commentary also identifies the estimated speed reduction and crash reduction effects of 11 key treatments. The greatest crash reduction effects (71%) are attributed to raised tables and road humps, followed by one-lane slow points (61%), road cushions and tactile surface treatments (60%), and roundabouts (55%).

Table 1: Description and use of LATM devices (Source: Austroads, 2020)

[1] Austroads (2020). Guide to Traffic Management Part 8: Local Street Management. Sydney, Austroads. https://austroads.gov.au/publications/traffic-management/agtm08