Recommendations - City of West Torrens - SA.Gov.au

Setting objectives for LATM allows a
scheme to be assessed, implemented
and measured against the desired
outcomes.
A possible approach to setting
objectives is as follows:
Primary objectives:
• improve the safety of the street
network
• reduce the environmental impact of
traffic.
Specific objectives:
• reduce speed
• reduce volumes
• reduce through traffic
• reduce heavy vehicles.
Secondary objectives:
• maintain access through the City for
residents
• avoid transferring traffic from one
street to another.
In practice, the above approach has
been used by the City of West Torrens
over many years of LATM studies and
traffic management.
Recommendation
• Adopt the above objectives for
LATM studies.
2.1 The need for and the
process for a LATM study
The need usually arises from:
• resident concerns about traffic
conditions in an area
• known through traffic issues and
increasing impact on the local area
• need to reduce traffic-related
problems on an area-wide basis
• traffic concerns arising from major
new developments or new road
projects in or abutting the area
• proactive approach to road safety in
the local area.
While a LATM is intended to provide
positive traffic outcomes to a local
area, there are negative effects that
would result, including:
• increased travel time for drivers
• increase in noise adjacent to devices
• impact on on-street parking
• impact on cyclists and pedestrians
• restricted access to properties
• effect on emergency service vehicles
• transfer of traffic from one street
to another
• enforcement issues and difficulties
• costs to Council.
A LATM study area is usually bounded
by arterial roads, other physical
barriers such as creeks, railways or
reserves, and in the case of the City
of West Torrens, the Adelaide Airport
boundaries.
The process involved in a LATM study
is generally as follows:
• prepare LATM study
• define the objectives
• develop options and plan for the
LATM
• design the approved LATM scheme
• implement the LATM scheme
• monitor and review.
The City of West Torrens has undertaken
many such LATM studies in past years.
The above summary provides the
background and the methodology
previously used in the City and such
a process is recommended to be
retained.
2.2 The need for a warrantbased
priority system for LATM
studies
The Austroads Guide to Traffic
Engineering Practice Part 10 lists three
possible warrant system to determine
priority for LATM decision making, ie:
• “Qualifying conditions” to merit
closer examination.
• Warrants expressed as acceptable
thresholds of stated criteria.
• Warrants, usually expressed as
points, to provide a basis for
priority ranking.
The simplest approaches to indicators
of the need for action comes in the
form of a “checklist” or sieve of
conditions, some of which may be
qualitative, that must apply in order for
a street to qualify for closer inspection.
This approach is compatible with a
one-off, street-bystreet approach to
traffic calming but is also useable in
area-wide LATM.
Source: Austroads
This has been the approach of the City
of West Torrens for many years. The
“sieving” of conditions include:
• assessment of the current street
conditions
• review of the traffic volumes, speeds
and commercial traffic
• review of through traffic usage
• analysis of the crash data
• adjacent land uses
• road hierarchy.
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Part 2 - Traffic Management | Objectives and Setting Criteria