Residential Street
Improvements
Streeton Drive
Executive Summary
1.0
Introduction
Roads ACT uses a Traffic Warrant System (TWS) to objectively assess the need for, and priority of, traffic
management and road safety measures on residential streets. The TWS takes into account traffic volume, speed,
crash history, volume of heavy vehicles and land use to provide a ranking for over 400 collector roads. This
relative ranking is used to prioritise and instigate studies on area wide Local Area Traffic Management
treatments.
As part of the 2012/13 Residential Street Improvement Program a list of priority streets were identified for
investigation. This report focuses on the priority street of Streeton Drive in the Weston Creek area from
Hindmarsh Drive in the north to Namatjira Drive in the south.
The aim of the project is to develop options to improve traffic conditions along Streeton Drive and to recommend a
program of works within the available capital works funding. An important part of this project is seeking feedback
from local residents and the surrounding community about what the issues are, what improvements should be
implemented and what options would best suit the local community.
Residents of Streeton Drive in Weston Creek and other road users have voiced concerns over traffic speed,
volume and road safety along Streeton Drive from Hindmarsh Drive in the north to Namatjira Drive in the south.
Roads ACT engaged AECOM Australia Pty Ltd to consult with the community, identify potential traffic calming
measures, and recommend a preferred treatment option and preliminary sketch plan.
To ensure that traffic management treatment options did not transfer traffic to other streets, the network of roads
surrounding Streeton Drive were assessed for existing problems and complaints, and to ensure no adverse
impact from improvements to Streeton Drive.
The study incorporated a technical analysis of traffic speed, volume and crash data along Streeton Drive and its
surrounding streets, as well as feedback obtained from consultation. The technical analysis included:
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An analysis of available traffic data (volume, speed and accident statistics);
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A review of complaints received by Roads ACT;
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A review of road, pedestrian and bicycle infrastructure including networks, shared paths and movements, as
well as public transport services such as frequency, times and routes of buses; and
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Traffic growth and the diversion of traffic due to works on Streeton Drive or other adjacent roads was
assessed using Canberra’s EMME strategic traffic model, for the weekday AM peak period.
The technical analysis was undertaken street by street with a particular focus on Streeton Drive, Darwinia
Terrace, Perry Drive, Fremantle Drive, Namatjira Drive and Bunbury Street.
2.0
Streets considered in study
2.1
Streeton Drive
Streeton Drive is a major collector road with a posted speed limit of 60 km/h, except near the school zone west of
Darwinia Terrace where it is 40km/h during school hours. The road is approximately 12.5m wide, with room for
parking on both sides. However, street parking is not well-utilised during the day.
The main issues on Streeton Drive are traffic volume and speed. Weekday volumes average over 9,000 vehicles
per day in the northern segment, and reach 6,000 vehicles per day in the middle segment. These volumes are
high for a major collector road with driveway access. During peak periods residents will have difficulty pulling into
and out of driveways and side roads and pedestrians will have trouble finding a safe gap to cross. These
difficulties are exacerbated by the high vehicle speeds north of Darwinia Terrace, with 85th percentile speeds of
about 68 km/h.
There were 83 crashes, including three injury crashes, on Streeton Drive in the last five year period. Most of these
crashes (50) were at the intersection with Hindmarsh Drive.
The issues of traffic speeds and volumes reflected in the data are reflected by concerns voiced by the local
community. They are also concerned with future traffic growth due to development in Molonglo, car parking
around the netball courts, and the school crossing at Chapman Primary School. Traffic modelling with Molonglo
indicates that there is likely to be moderate traffic growth on Streeton Drive over the next 20 years, with an
expected 11% increase in traffic volumes on Streeton Drive south of Hindmarsh Drive. Some of this growth could
be due to future development along Fremantle Drive.
The main objectives for treatments on Streeton Drive are to reduce speeds and volumes north of Darwinia
Terrace, address parking issues adjacent to the netball courts, and improve safety for pedestrians crossing the
road, driveway access and traffic safety generally.
Roundabouts, kerbside lanes, kerb extensions and centre islands are all road narrowing or horizontal deflection
measures which may be helpful in reducing speed or traffic volumes along Streeton Drive. Painted centre islands
can also help provide room for right turns into driveways or side roads. However, the use of these must be
balanced with any need for on-street parking. It may be possible to combine or alternate the use of centre and
kerbside treatments to satisfy multiple objectives.
Given the range of traffic issues on the surrounding streets, and the pattern of minor collector roads in the local
area, care is required to ensure that the installation of traffic calming devices on this road does not have the
unintended consequence of encouraging drivers to choose alternative routes through the neighbourhood.
2.2
Darwinia Terrace
Darwinia Terrace is classified as a major collector in the hierarchy of ACT roads, and has a posted speed limit of
60 km/h reflecting this classification. The road is approximately 10.3m wide and there is little use of on-street
parking.
Its volume of 2,800 to 3,200 vehicles per day is at the low end of the range for a major collector. However, traffic
volumes on this road are likely to increase in future as a result of the development of Molonglo over the next 20
years.
Average recorded speeds are less than its 60 km/h speed limit indicating that speeding is not a significant
problem. However, there have been 17 crashes including two pedestrian crashes on this road in the last five year
period and reducing the speeds would help reduce crash risks. The community is particularly concerned about
pedestrians and school children crossing the road in the vicinity of Thring Street.
The main objectives for treatments on Darwinia Terrace are to reduce traffic speeds, improve pedestrian safety in
the vicinity of Thring Street, and mitigate potential traffic growth associated with the future development of
Molonglo.
Kerbside lanes, kerb extensions and centre islands are all road narrowing, or horizontal deflection measures
which may be helpful in reducing speed along Darwinia Terrace. A centre island pedestrian refuge can help
pedestrians crossing the road.
2.3
Perry Drive
Perry Drive is a minor collector road with a speed limit of 50 km/h, except in the school zone east of Thring Street
where it is 40km/h during school hours. The road is approximately 10.3m wide and there is little use of on-street
parking, except near the school and shops.
Compliance with the school zone speed limit is strongest during school arrival and dismissal times. During the
school day, the average speed was approximately 41 km/h. Over the entire day, the average speed was 47 km/h
and 85th percentile speed was 55 km/h at the counter location near the school. The observed traffic volume of
over 4,000 vehicles per day is high for a minor collector road. This is likely to increase in future as a result of
traffic generated by the growth of Molonglo.
Community concerns for traffic safety are supported by the crash data which indicates 32 crashes on Perry Street
in five years including four injuries and one pedestrian crash. There are additional concerns raised regarding
parking in the vicinity of the school.
The main objectives for treatments on Perry Drive are to reduce speeds, improve traffic safety along the street,
improve parking and pedestrian safety in the vicinity of the school, and mitigate potential traffic growth associated
with the future development of Molonglo.
Kerbside lanes, kerb extensions and centre islands are all road narrowing, or horizontal deflection measures
which may be helpful in reducing speed along Perry Drive. A centre island pedestrian refuge can help pedestrians
crossing the road. A median island is already in place near the Chapman Primary School, so a vertical deflection
device such as a raised platform crossing may be considered for further speed reduction.
2.4
Namatjira Drive (from Hindmarsh Drive to south of Kapunda Street)
Namatjira Drive is a major collector road with a posted speed limit of 60 km/h, except in the school zone north of
Badimara Street where it is 40km/h during school hours. The road is approximately 12.5m wide and incorporates
a cycle lane between Badimara Street and Hindmarsh Drive. There is little use of on-street parking because of the
cycle lanes north of Badimara Street and safety concerns south of Badimara Street.
The main issues facing Namatjira Drive are traffic volume and speed. Weekday volumes are over 10,000 vehicles
per day. This volume is very high for a major collector road with driveway access. Residents will have difficulty
pulling into and out of driveways and side roads and pedestrians will have trouble finding a safe gap to cross.
These difficulties are exacerbated by the fact that, in the southern segment, average vehicle speeds are over the
60 km/h limit and 85th percentile speeds (the speed at which 85 per cent of the surveyed traffic is travelling at or
below) are 67 to 70 km/h.
There were 91 crashes, including six injury crashes in a recent five year period on Namatjira Drive. Many crashes
(42) occurred at the intersection with Hindmarsh Drive. Other concentrations of crashes included the intersection
at Bunbury Street, and the segment of Namatjira Drive from Streeton Drive to Kapunda Street.
The main objectives for treatments on Namatjira Drive are to reduce speeds and volumes and improve traffic
safety between Streeton Drive and Kapunda Street. Care should be taken to not encourage traffic to divert to
lower order roads in the local area.
Existing bike lanes north of Badimara Street narrow the roadway and appear to be having some effect on traffic
speed. In the southern section, road narrowing and horizontal deflection measures such as roundabouts, kerbside
lanes, kerb extensions and centre islands may be helpful in reducing speed along Namatjira Drive. Painted centre
islands can help provide room for right turns into driveways or side roads; however, the use of these must be
balanced with the need for on-street parking. It may be possible to combine or alternate the use of centre and
kerbside treatments to satisfy multiple objectives.
2.5
Fremantle Drive
Fremantle Drive is a minor collector road with a speed limit of 50 km/h, except in the school zone east of Thring
Street where it is 40km/h during school hours. The road is approximately 10.3m wide and there is little use of onstreet parking.
During the school day, the average speed was approximately 41 km/h. Over the entire day, the average speed
was 43 km/h and 85th percentile speed was 55 km/h at the counter location in the school zone near Bunbury
Street. The weekday volume of 2,400 vehicles per day on Fremantle Drive south of Bunbury Street is within the
expected range for a minor collector.
There are traffic access and safety concerns regarding the northern intersection with Streeton Drive. Access is a
problem because of the high volumes, but there is no significant crash history here.
There are also concerns regarding speed and potential traffic growth and diversion onto Fremantle Drive. There is
some historic evidence of excessive speed, but this is not supported by recent surveys. Traffic modelling suggests
that there could be some diversion of traffic to Fremantle Drive if changes are made to Streeton Drive, as well as
growth due to future development on vacant land on Fremantle Drive.
The main objective of treatments on Fremantle Drive is to reduce traffic diversion due to future traffic
management works on Streeton Drive. To achieve these objectives, roundabouts and road narrowing measures
may be considered along Fremantle Drive.
2.6
Bangalay Crescent
Bangalay Crescent is a minor collector road with a speed limit of 50 km/h. The road is approximately 10.3m wide
and there is little use of on-street parking.
Average speeds of 54 km/h and 85th percentile speeds of 62 km/h on Bangalay Crescent are higher than
desirable. An observed weekday volume of 1,900 vehicles per day east of Casuarina Street is well within the
expected range for a minor collector road. There were very few crashes along the length of the street, but the
crash history points to a safety concern regarding the intersection with Hindmarsh Drive.
Road narrowing or horizontal deflection measures may be considered in future along Bangalay Crescent,
although as a low priority compared with other streets in the area, because of the relatively low crash record.
Changes to Streeton Drive may cause some diversion in traffic using parts of Bangalay Crescent.
2.7
Bunbury Street
Bunbury Street is a minor collector road with a speed limit of 50 km/h, except at its western end where it is 40km/h
during school hours. The road is approximately 10.3m wide and there is quite significant use of on-street parking.
At the eastern end of Bunbury Street, average speeds of 54 km/h and 85th percentile speeds of 63 km/h are
higher than desirable. An observed weekday volume of 2,100 vehicles per day is well within the expected range
for a minor collector road. There were several crashes along the length of the street, and the crash history points
to a safety concern regarding access to driveways and the intersection with Namatjira Drive.
The main objectives of treatment on Bunbury Street are reducing traffic speed, improving traffic safety, especially
at its intersection with Namatjira Drive. To achieve these objectives, road narrowing, kerb extensions and centre
islands may be considered along Bunbury Street.
3.0
Future Traffic Growth
Existing and future traffic patterns through the area, as well as potential traffic growth due to Molonglo
development were modelled. The highest increases in traffic in the study area are expected to occur on Darwinia
Terrace, Perry Drive and parts of Streeton Drive, Fremantle Drive and the southern end of Namatjira Drive. The
streets showing the highest increase in through traffic are Darwinia Terrace, Streeton Drive and the southern end
of Namatjira Drive.
4.0
Development of Options: Concept Designs
Considering the data above and community feedback (see consultation), two traffic management concepts were
developed to improve traffic conditions on Streeton Drive, as well as issues on surrounding streets identified
during the analysis of traffic data and from community feedback. Both concepts proposed raised platforms on
Streeton Drive and Perry Drive, and the same locations for pedestrian refuges.
Concept 1 proposed marked shoulders which look like a parking lane and can accommodate cyclists and buses
and act as a shoulder. This is proposed on parts of all streets in Concept 1 while Concept 2 proposed centre
medians on most streets. The locations of some proposed roundabouts and channelised right turns varied in both
concepts. Both devices were effective in improving traffic safety.
Maps showing the treatments suggested for inclusion in the two concepts are given in Figure 1 and Figure 2. The
estimated cost (inclusive of GST) is $1.9 million for Concept 1 and $2.9 Million for Concept 2.
Prior to undertaking community consultation, a preliminary assessment was completed of the relative costs,
benefits and detriments of the two concept designs. The following table shows how effective each of the concepts
is likely to be in addressing the objectives of the proposed schemes.
Objective
Concept 1
Concept 2
Reduce travelling speeds
– an issue of concern on all
streets in the area
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More effective in reducing
speeds on Streeton Drive,
Bunbury Street and Perry Drive
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More effective in reducing
speeds on Fremantle Drive and
Namatjira Drive
Improve safety at intersections
- mostly of concern at
intersections along Streeton
Drive, Hindmarsh Drive and
Namatjira Drive
-
More effective in improving
safety at intersections along
Streeton Drive
-
More effective in improving
safety at intersections along
Namatjira Drive
Improve pedestrian safety
-
More effective in improving
-
More effective in improving
Objective
Concept 1
- a particular issue of concern on
Streeton Drive, Perry Drive and
Darwinia Terrace
Concept 2
pedestrian safety on Streeton
Drive and Perry Drive
pedestrian safety on Namatjira
Drive
Reduce traffic volumes
- an issue of concern on Streeton
Drive and Namatjira Drive
-
More effective in reducing traffic
volumes on Streeton Drive
-
More effective in reducing
traffic volumes on Namatjira
Drive
Discourage “rat running”
- a potential issue on all streets in
the area, but particularly Perry
Drive and Darwinia Terrace
-
Effective in reducing rat running
on local streets in the area
-
Effective in reducing rat
running on local streets in the
area
Cost
- an issue for all streets
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Total cost about $2M
-
Total cost about $3M
Roundabouts & centre islands
add to the cost of this concept
Other community issues
- parking adjacent to the netball
courts on Streeton Dr is of
particular concern
-
Includes safer access to netball
courts
Investigations for extra parking
being considered
-
Includes safer access to netball
courts
Investigations for extra parking
being considered
5.0
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Consultation
Consultation with the local community was an important part of the study and was conducted in three stages.
Stage 1 sought open feedback about any issues the study should be aware of, and Stage 2 sought preferences
for either of the two concepts (Concept 1 and Concept 2) that were produced from a combination of community
feedback and technical analyses. Stage 3 informed the community about the final traffic management scheme.
The first round of consultation (stage 1) was conducted over five weeks in November and December 2013 and the
second (stage 2) for six weeks in March and April 2013. Stage 3 informed the community about the project
outcomes and occurred in mid June 2013.
In stage 1 approximately 247 people participated in the feedback process. Key areas of concern included
speeding (58% of respondents), parking issues (42%), ‘rat running’ (31%), excessive traffic volumes (29%),
intersection safety (29%) and pedestrian safety (27%). Please note that ‘rat running’ was terminology used by
many community members.
In this stage, speeding, excessive traffic volumes and parking issues were identified as requiring immediate
solutions. Comments received indicated some concern over placing speed humps or chicanes on Streeton Drive.
Preferred treatments on all streets included roundabouts, lane narrowing and pedestrian crossings.
In stage 2, approximately 188 people participated in the engagement process. The consultation presented two
concepts to the community and sought their preference for the concepts and for the proposed treatment
measures within them.
Approximately half of the respondents preferred Concept 1, with approximately a quarter preferring Concept 2.
The remaining quarter of participants did not support any traffic management treatments, particularly on Streeton
Drive.
All feedback received in the consultation stages was collated and analysed by the technical team, and where
appropriate, considered and incorporated into the final scheme for improvement.
6.0
Final Traffic Management Scheme – the Master Plan
A traffic management scheme has been finalised to improve traffic conditions for the study area.
In view of the results of the technical analysis and the feedback received from the community, and considering the
technical effectiveness of the proposed treatments, the final scheme is based on Concept 1 but also incorporates
some alternative treatments suggested and supported by the community.
The objectives of this scheme are to:
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reduce travelling speeds
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improve safety at intersections
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improve pedestrian safety
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reduce traffic volumes
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discourage people taking shortcuts through minor roads.
It is important to note that the final scheme is an overall master plan for the area and that not all proposed devices
will be installed at once. The master plan will guide the implementation of the scheme over a number of years due
to annual budgetary constraints.
In that context, priorities have been assigned to the proposed treatments based on the results of the technical
analysis and the feedback from the community. It is anticipated that the detailed design and implementation of
Priority 1 treatments will take place in 2013/14.
Priority 1 treatments include:
Streeton Drive
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Marked shoulders:

from Hindmarsh Drive to the roundabout at Darwinia Terrace (including near the netball courts)

between Namatjira Drive and Fremantle Drive (south)
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Channelised right turn arrangement at Sherratt Place
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Pedestrian refuge island between Hindmarsh Drive and Fremantle Drive
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Pedestrian refuge island north of the roundabout at Darwinia Terrace
Darwinia Terrace
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Pedestrian refuge island between Streeton Drive and Thring Street
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Pedestrian refuge island between Thring Street and Perry Drive
Bunbury Street
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Two centre islands:

close to Fremantle Drive intersection (near walkway)

near Shenton Crescent
An evaluation of the effectiveness of these treatments will take place six months after their implementation. The
evaluation will include a technical analysis of the scheme’s impacts and the residents’ views of the extent to which
the stated objectives were achieved. Further implementation of Priority 2 and 3 treatments will depend on the
results of this evaluation to ensure they are still effective and viable options for the people that live, work, play,
shop, go to school and commute in the study area.
The estimated probable cost of the Priority 1 treatments is $200,000. The benefit to cost analysis indicates that
the proposed priority 1 treatments have a benefit/cost ratio of 1.25. It should also be noted that the local area
traffic management treatments will have additional benefits beyond the benefits considered in the benefit-cost
analysis. By reducing traffic speeds in the neighbourhood, the treatments are expected to improve residential
amenity and better support active modes of transport such as walking and cycling.
Figure 1:
Traffic management concept 1
Figure 2:
Traffic management concept 2
Figure 3: Final recommended scheme (Master Plan) and priorities of works