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Low Cost Safety Improvements Roads ACT 27 November 2012 Document No. 60271823RPTRA001_2

DR AFT

Low Cost Safety Improvements Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive


AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

DR AFT

Low Cost Safety Improvements Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

Prepared for Roads ACT

Prepared by AECOM Australia Pty Ltd Level 2, 60 Marcus Clarke Street, Canberra ACT 2600, Australia T +61 2 6201 3000 F +61 2 6201 3099 www.aecom.com ABN 20 093 846 925

27 November 2012

60271823

AECOM in Australia and New Zealand is certified to the latest version of ISO9001 and ISO14001.

© AECOM Australia Pty Ltd (AECOM). All rights reserved. AECOM has prepared this document for the sole use of the Client and for a specific purpose, each as expressly stated in the document. No other party should rely on this document without the prior written consent of AECOM. AECOM undertakes no duty, nor accepts any responsibility, to any third party who may rely upon or use this document. This document has been prepared based on the Client’s description of its requirements and AECOM’s experience, having regard to assumptions that AECOM can reasonably be expected to make in accordance with sound professional principles. AECOM may also have relied upon information provided by the Client and other third parties to prepare this document, some of which may not have been verified. Subject to the above conditions, this document may be transmitted, reproduced or disseminated only in its entirety.

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AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

DR AFT

Quality Information Document

Low Cost Safety Improvements

Ref

60271823

Date

27 November 2012

Prepared by

Leigh Palmer, Michael Jollon

Reviewed by

Tim Rampton

Revision History Authorised

Revision Date

Details

1

10-Aug-2012

Draft Report

2

27-Nov-2012

Final Draft Report

Revision

Name/Position Tim Rampton Associate Director Tim Rampton Associate Director

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Signature


AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

DR AFT

Table of Contents Executive Summary 1.0 Introduction 1.1 Overall objective 1.2 Project tasks 2.0 Hindmarsh Drive/ Launceston Street and Hindmarsh Drive/ Eggleston Crescent 2.1 Review of previous studies 2.2 Results of modelling safety improvements 2.3 Low cost safety measures 2.4 Expected crash reductions 2.5 Economic Analysis 2.6 Recommendation 3.0 Melrose Drive / Theodore Street 3.1 Background 3.2 Updated crash analysis 3.3 Traffic characteristics 3.4 Site inspection 3.5 Remedial measures 3.6 Expected crash reductions 3.7 Economic analysis 3.8 Recommendation 4.0 Wentworth Avenue / Mildura Street / Leichhardt Street 4.1 Background 4.2 Crash analysis 4.3 Traffic characteristics 4.4 Site inspection 4.5 Remedial measures 4.6 Expected crash reductions 4.7 Economic analysis 4.8 Existing deficiencies and maintenance items 4.9 Recommendation 5.0 Kuringa Drive 5.1 Background 5.2 Updated crash analysis 5.3 Traffic characteristics 5.4 Site inspection 5.5 Remedial measures 5.6 Expected crash reductions 5.7 Economic analysis 5.8 Existing deficiencies and maintenance items 5.9 Recommendation

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AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

DR AFT

List of Tables Table 1 Table 2 Table 3 Table 4 Table 5 Table 6 Table 7 Table 8 Table 9 Table 10 Table 11 Table 12 Table 13 Table 14 Table 15

Summary of Benefit to Cost Analysis Hindmarsh Drive / Launceston Street Summary of Benefit to Cost Analysis Hindmarsh Drive / Eggleston Crescent Benefit/cost analysis Hindmarsh Drive Crash comparison before and after treatment Melrose Drive / Theodore Street Updated crash history Melrose Drive / Theodore Street Crash factor matrix Melrose Drive / Theodore Street Benefit/cost analysis Melrose Drive / Theodore Street Crash comparison before and after treatment Wentworth Avenue / Mildura Street / Leichhardt Street Updated crash history Wentworth Avenue / Mildura Street / Leichhardt Street Crash factor matrix Wentworth Avenue / Mildura Street / Leichhardt Street Benefit/cost analysis Wentworth Avenue / Mildura Street / Leichhardt Street Crash comparison before and after treatment Kuringa Drive Updated crash history Kuringa Drive Crash factor matrix for Kuringa Drive Benefit/cost analysis Kuringa Drive

5 6 9 10 11 12 18 20 21 22 28 30 31 32 43

Option 1 b – Lane reduction on Hindmarsh Drive Enhanced speed limit and side road warning signs for Hindmarsh Drive intersections Additional signs at Launceston Street Sign relocation at Eggleston Crescent Melrose Drive/ Theodore Street ACTION Weekday Bus Service ACT Walking and Cycling Map: Melrose Drive / Theodore Street detail Low-Cost Safety Option for Melrose Drive / Theodore Street ACTMAPi aerial view of Wentworth Avenue / Mildura Street / Leichhardt Street ACTION Weekday Bus Service ACT Walking and Cycling Map: Wentworth Avenue detail Low Cost Safety Improvements Wentworth Avenue / Mildura Street / Leichhardt Street Kuringa Drive Source: Google Earth Pro Kuringa Drive / Tillyard Drive Curve Source: ACTMAPi Kuringa Drive back-to-back curves Source: ACTMAPi Kuringa Drive / Kingsford Smith Drive Source: ACTMAPi ACTION Weekday Bus Service ACT Walking and Cycling Map: Kuringa Drive detail Tillyard Street curve detail for RRPM treatment extents Back to back curve detail for RRPM treatment extents Kingsford Smith Drive curve detail for RRPM treatment extents Enhanced speed limit marking on Kuringa Drive Enhanced curve warning and speed signs on Kuringa Drive

6 7 8 8 13 14 15 17 23 24 25 27 33 34 34 35 36 36 39 39 40 40 41

List of Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 22 Figure 23

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AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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DR AFT

Executive Summary Roads ACT have commissioned AECOM Australia Pty Ltd to reinvestigate, analyse and provide recommendations for low-cost safety improvements at certain intersections on Hindmarsh Drive, Melrose Drive, Wentworth Avenue, and on the midblock segment of Kuringa Drive between Tillyard Street and Kingsford Smith Drive. These analyses included the examination of the most recently available five year crash history for each site to ascertain the contributory factors and develop remedial measures for each site.

Hindmarsh Drive / Launceston Street and Hindmarsh Drive / Eggleston Crescent Microsimulation modelling of a lane reduction option on Hindmarsh Drive Black spot safety studies were completed for the intersections at Eggleston Crescent and Launceston Street in 2011 and 2012. An option (1b) was identified in the earlier study as a possible solution. It proposed to reduce the number of through traffic lanes along Hindmarsh Drive from the existing three lane layout to a two lane through movement at the intersection, with a dedicated continuous slip lane for right and left turners out of both intersections onto Hindmarsh Drive In this study, the Option 1b lane reduction was modelled using Commuter microsimulation software. Simulation of the proposed lane arrangement indicated it will not provide adequate capacity to service the existing AM peak hour volumes. An alternative lane arrangement (Option 1c) was considered which reduced the number of through lanes on the near side approach at each t-intersection: westbound Hindmarsh Drive at Eggleston Crescent and eastbound Hindmarsh Drive at Launceston Street. At the intersections an ‘add lane’ was formed to allow for right turners out of the side streets to have a dedicated lane on Hindmarsh Drive. The model has indicated that the proposed changes as part of Option 1c would not cause any significant traffic issues along the corridor. Furthermore, this option will reduce the number of lanes required to be crossed (oneway) from three to two, in order to undertake a right turn. This in turn should improve the legibility to drivers and improve safety at the intersections. Overall Option 1C provides a good balance between maintaining capacity along Hindmarsh Drive and safety improvements at the intersections of Launceston Street and Eggleston Crescent. As such, should be considered as a possible solution to the current safety concerns at the two intersections.

Low Cost Treatments At the intersection of Hindmarsh Drive and Launceston Street, the following low cost safety measures were identified to improve existing safety conditions. -

Install side road warning signs on the nearside eastbound approach of Hindmarsh Drive

-

Install enhanced speed limit signage on both directions of Hindmarsh Drive Enhanced signage may include LED displays or larger signs

-

Install a second Stop sign on the splitter island Launceston Street approach

-

Install a Keep Right sign on the seagull island

At the intersection of Hindmarsh Drive and Eggleston Crescent, it is recommended to -

Install side road warning signs on the nearside eastbound approach of Hindmarsh Drive

-

Install enhanced speed limit signage on both directions of Hindmarsh Drive

-

Relocate the Give Way warning sign on Eggleston Crescent to improve its visibility

The indicative implementation cost for this option is $15,000. Potential savings from crash reductions were computed, and a benefit/cost ratio of 2.63 was determined. This indicates the treatment would return over two and half times its cost in crash benefits.

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AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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DR AFT

The proposal for enhanced speed limit, priority and warning signs are recommended along Hindmarsh Drive at Launceston Street and Eggleston Crescent as a form of low cost improvement. Increased speed limit enforcement by both police and automated means, is also recommended. However, it should be noted that higher safety improvement could be gained with more capital expenditure (e.g.: signalising the intersections) although investigation into this type of treatment was explored in the original study.

Melrose Drive / Theodore Street Safety improvements were made under the black spot program to the intersection of Melrose Drive and Theodore Street in late 2006. These improvements included re-alignment of the right turn and left turn entry into Theodore Street and construction of splitter Island to re-align entry into Melrose Drive. An assessment of the improvements was conducted by Roads ACT in 2010. A total increase of 140% in the number of crashes was detected at this intersection. The recorded crashes for the five year period from January 2007 until December 2011 were analysed. Thirtyseven crashes have occurred at the intersection of Melrose Drive and Theodore Street. Of these crashes, 4 were injury crashes and the rest were property damage only crashes. Almost half, 18 of 37 crashes in the 5 year period involved vehicles turning right out of Theodore Street. Most of the crashes (65%) occurred outside of peak periods. The proposed remedial measure for this intersection is enhancing intersection conspicuity with dual intersection warning signs on Melrose Drive, and marking the intersection on northbound Melrose Drive with a Keep Clear box. The indicative implementation cost for this option is $15,000. Potential savings from crash reductions were computed, and a benefit/cost ratio of 2.78 was determined. This indicates the treatment would return over two and half times its cost in crash benefits. The proposal for Intersection warning signs and a ‘keep clear’ is recommended on Melrose Drive as a form of low cost improvement. However, it should be noted that higher safety improvement could be gained with more capital expenditure (e.g.: signalising the intersection) although investigation into this type of treatment was not explored in this study.

Wentworth Avenue / Mildura Street / Leichhardt Street Safety improvements were made in 2007 under the black spot program to the intersection of Wentworth Avenue, Mildura Street and Leichhardt Street. The improvements included installation of traffic islands, signs and line marking. An assessment of the improvements was conducted by Roads ACT in 2010. There was one fatal adjacent approach crash in the after study period. Opposing turn collisions, lane side swipes and manoeuvring crashes all increased. An overall 8% increase in the total number of crashes was detected at this intersection after the treatment. The recorded crashes for the five year period from January 2007 through December 2011 were analysed. Sixteen crashes have occurred at the intersection of Melrose Drive and Theodore Street in the five year period. Of these crashes, 1 was a fatal crash and the rest were property damage only crashes. Crashes were well distributed among types; however, 9 of 16 were right angle crashes from adjacent approaches. The recommended low cost safety improvements at the intersection of Wentworth Avenue, Mildura Street and Leichhardt Street include: -

Reposition existing Give Way sign on Mildura Street closer to intersection

-

Supply additional Give Way sign on the median island on Mildura Street

-

Refresh paint and install Reflective Pavement Markers (RPM) for all median crosshatching in intersection.

The indicative implementation cost for this option is $15,000. Potential savings from crash reductions were computed, and a benefit/cost ratio of 1.34 was determined. This indicates the treatment would result in a crash reduction value only slightly greater than installation and maintenance costs. P:\CBR\60271823_LowCostSafety_Imprvmnts2012\8. Issued Docs\8.1 Reports\60271823RPTRA001_2.docx Revision 2 - 27 November 2012


AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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DR AFT

Despite not meeting the desired ratio of benefits outweighing costs by a factor of two, the low cost safety improvements at Wentworth Avenue and Mildura Street / Leichhardt Street may still be considered for their ability to improve safety at the intersection. If the restriping of the approach islands and raised pavement markers are not initially installed, replacement of a second Give Way sign on the median of Mildura Street should be considered as a maintenance item.

Kuringa Drive Safety improvements were made under the black spot program to the mid-block section of Kuringa Drive between Tillyard Drive and Kingsford Smith Drive in June 2008. These improvements included Installation of warning signs, guardrails and lighting. There were 23 crashes on this segment of Kuringa Drive in four year period after the treatment. These crashes include one fatality, 8 injury crashes, and 14 property damage crashes. The crash frequency is almost 8 crashes per year, an increase over the five crashes per year in the period studied before the treatment was installed. The most common crash types were single vehicles leaving the roadway. The bulk of the crashes, 20 of 23, occurred in the westbound direction. About half were on wet roads. More than half occurred on weekends or public holidays. The proposed remedial measures for this midblock road section are: -

Improve speed limit signage with larger signs at the beginning of the road segment and repeater signs along the road. To highlight the change in speed limit on the approach form the west, the speed limit should be marked in the westbound lane after Kingsford Smith Drive.

-

Enhance curve warning and advisory speed signs by installing on both sides of the road leading into the back to back curve and repeating curve warning signs on both sides of the road in between back to back curves.

-

Increase supply of retro-reflective raised pavement markers (RRPMs) by halving spacing along the centreline and edge lines approaching and through all signposted curves.

The indicative implementation cost for this option is $15,000. Potential savings from crash reductions were computed, and a benefit/cost ratio of 4.60 was determined. This indicates the treatment would return over four times its cost in crash benefits. Existing deficiencies and maintenance items include: overgrown trees should be cut back, missing and damaged signs and guide posts should be replaced, and an eroded shoulder in the westbound lane should be repaired. The proposal for enhanced speed limit signs and marking, curve warning signs and retro-reflective raised pavement markers is recommended for the mid-block section of Kuringa Drive between Tillyard Street and Kingsford Smith Drive as a form of low cost improvement. However, it should be noted that higher safety improvement could be gained with more capital expenditure (e.g. realignment) although investigation into this type of treatment was not explored in this study. It should be noted that this form of treatment relies on a high level of driver compliance. As such, this location should be considered for increased speed enforcement. Extra attention should be given in the back to back curves. This enforcement should be focused on the westbound traffic, particularly on straight segments and in the back to back turns. Both police speed enforcement and automated speed enforcement means should be considered.

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AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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1.0

Introduction

Roads ACT have commissioned AECOM Australia Pty Ltd to reinvestigate, analyse and provide recommendations for low-cost safety improvements at intersections on Hindmarsh Drive, Melrose Drive and Wentworth Avenue, and on a midblock segment of Kuringa Drive. These analyses included the examination of the most recently available five year crash history for each site to ascertain the contributory factors and develop remedial measures for each site. The following sites were examined. Intersections 1.

Hindmarsh Drive / Launceston Street

2.

Hindmarsh Drive / Eggleston Crescent

3.

Melrose Drive / Theodore Street

4.

Wentworth Avenue / Mildura Street / Leichhardt Street

Mid-Block Locations 1.

1.1

Kuringa Drive between Kingsford Smith Drive and Tillyard Drive Crescent

Overall objective

The ACT Road Safety Strategy for 2011 – 2020 aims to meet a national goal of at least a 30% reduction in fatalities and serious injuries by 2020. Providing safe roads and roadsides is one component of an integrated approach to meet this goal. Our study will provide the ACT Government with cost effective and safe upgrade options which will allow for informed recommendations to be made. The aim of the project is to: -

Identify the contributory factors associated with crashes at each site

-

Identify any features seen during site inspections, which may adversely contribute to crashes at this location

-

Suggest remedial measures

1.2

Project tasks

For the Hindmarsh Drive locations: -

previous studies have been reviewed

-

recommended options have been modelled through computer aided micro-simulation to determine their ability to serve existing and expected future volumes of traffic

-

additional low cost safety improvements have been explored for implementation in lieu of the modelled options.

For the re-investigations of intersections on Melrose Drive and on Wentworth Avenue, and Kuringa Drive: -

updated analysis has been performed on the last five years of crash data

-

crash factor matrices have been developed

-

low-cost countermeasures have been developed

-

preferred countermeasures have been recommended

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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2.0

Hindmarsh Drive/ Launceston Street and Hindmarsh Drive/ Eggleston Crescent

2.1

Review of previous studies

Crash Analysis The crash analysis performed for the Hindmarsh Drive and Launceston Street intersection indicated that 27 crashes occurred during the five year period January 2006 to December 2010. Of these crashes, three (11%) were injury crashes and 24 were property damage crashes. A large proportion of crashes (10 of 27) were right angle (adjacent approach) crashes—all of these involved right turns out of Launceston Street. This movement was also implicated in two of the three injury crashes. At the Hindmarsh Drive and Eggleston Crescent intersection, there were 32 recorded crashes in the period January 2006 to December 2010. Of these crashes, four (12.5%) were injury crashes and the rest were property damage only crashes. The greatest number of crashes were rear-end collisions. All injury crashes were the result of adjacent approach crashes. Half of the adjacent approach crashes and 40% of the rear-end crashes involved the left turn out of Eggleston Crescent.

Site Inspection The observations noted at Hindmarsh Drive and Launceston Street included: -

Sight distance is reasonable at the intersection; however it seems that drivers turning right out of Launceston Street don’t select a safe gap, possibly due to difficulty detecting gaps in three lanes on Hindmarsh Drive.

-

Right turn movements out of Launceston Street don’t have a dedicated acceleration lane in the median on Hindmarsh Drive; this may result in frustration and taking unsafe gaps particularly in peak hours.

-

There are missing connecting footpaths on either side of Launceston Street.

-

Pavement has deteriorated at Launceston Street particularly on the left turn lane from Hindmarsh Drive.

-

The relatively straight alignment and pavement width of Hindmarsh Drive tends to invite a higher operational speed than the posted 80 km/h.

The observations noted at Hindmarsh Drive and Eggleston Crescent included: -

The majority of turning movements at the intersection are right turn movements into Eggleston Crescent and left turn movements out of Eggleston Crescent (in the PM)

-

Many drivers turning right into Eggleston Crescent use Eggleston Crescent to connect to other Woden Valley suburbs via Macfarlane Crescent.

-

Drivers turning right into and out of Eggleston Crescent may misjudge the gap crossing three lanes which are travelling at 80 km/h.

-

Sight lines of vehicles in the left turn lane out of Eggleston Crescent can be obscured by vehicles turning right. This may result in hesitation and may be a factor in rear-end crashes, as the driver of the second vehicle may have a better view than the drive of the lead vehicle.

Options Analysis Each option was allocated an indicative implementation cost and assessed for potential crash reduction savings. The results of the cost benefit analysis for Hindmarsh Drive and Launceston Street are summarised in Table 1. Table 1

OPTION

Summary of Benefit to Cost Analysis Hindmarsh Drive / Launceston Street

Treatment

Cost

B/C Ratio

NPV

OPTION 1

Acceleration Lane

$200,000

0.17

-$224,098

OPTION 2

Signalisation

$525,000

0.51

-$344,055

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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Both options failed to yield benefits in excess of their costs. As a result, neither of the options were considered viable for implementation. The results of the cost benefit analysis for Hindmarsh Drive and Eggleston Crescent are summarised in Table 2. Table 2

OPTION

Summary of Benefit to Cost Analysis Hindmarsh Drive / Eggleston Crescent

Treatment

Cost

B/C Ratio

NPV

OPTION 1 a

Lane reduction of Hindmarsh Drive at Eggleston Crescent

$94,000

2.66

$210,765

OPTION 1 b

Lane reduction of Hindmarsh Drive at Eggleston Crescent and at Launceston Street

$230,000

2.09

$337,305

Median closure with left turn deceleration / acceleration lanes

$122,000

3.54

$419,354

$370,000

0.58

-$209,491

OPTION 2

OPTION 3

Closure of the subject intersection with installing new signalised intersection at Hindmarsh Dr / Launceston St. / MacDonald St

Options 1a reducing from three through lanes to two at Eggleston Crescent; and Option 1b, reducing from three through lanes to two at Eggleston Crescent and at Launceston Street were both regarded as viable options. Option 1b (see Figure 1), was recommended because it offered effective crash reductions for two intersections and maintained consistency and driver expectations.

Figure 1

Option 1 b – Lane reduction on Hindmarsh Drive

With traffic volumes on three lanes of Hindmarsh Drive estimated at 2,300 vehicles per hour in the peak direction, it was expected that the recommendation may increase safety without significantly increasing delays. However, it was noted that further analysis would need to be undertaken before implementation was considered.

2.2

Results of modelling safety improvements

In this study, the Option 1b lane reduction was modelled using Commuter microsimulation software. Simulation of the proposed lane arrangement indicated it will not provide adequate capacity to service the existing AM peak hour volumes. An alternative lane arrangement (Option 1c) was considered which reduced the number of through lanes on the near side approach at each t-intersection: westbound Hindmarsh Drive at Eggleston Crescent and eastbound Hindmarsh Drive at Launceston Street. At the intersections an ‘add lane’ was formed to allow for right turners out of the side streets to have a dedicated lane on Hindmarsh Drive. The model has indicated that the proposed changes as part of Option 1c would not cause any significant traffic issues along the corridor. Furthermore, this option will reduce the number of lanes required to be crossed (one-

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AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

DR AFT

way) from three to two, in order to undertake a right turn. This in turn should improve the legibility to drivers and improve safety at the intersections. Overall Option 1C provides a good balance between maintaining capacity along Hindmarsh Drive and safety improvements at the intersections of Launceston Street and Eggleston Crescent. As such, should be considered as a possible solution to the current safety concerns at the two intersections.

2.3

Low cost safety measures

At the intersection of Hindmarsh Drive and Launceston Street, possible low cost safety measures were identified to improve existing safety conditions. -

Install side road warning signs on the nearside eastbound approach of Hindmarsh Drive

-

Install enhanced speed limit signage on both directions of Hindmarsh Drive Enhance signage may include LED displays or larger signs

-

Install a second Stop sign on the splitter island Launceston Street approach (this approach is already controlled with a Stop sign)

-

Install a Keep Right sign on the seagull island

At the intersection of Hindmarsh Drive and Eggleston Crescent, it is recommended to -

Install side road warning signs on the nearside eastbound approach of Hindmarsh Drive

-

Install enhanced speed limit signage on both directions of Hindmarsh Drive

-

Relocate the Give Way warning sign on Eggleston Crescent to improve its visibility

Increased speed limit enforcement by both police and automated means, is recommended for both locations

Figure 2

Enhanced speed limit and side road warning signs for Hindm arsh Drive intersections

The estimate of probable cost to install this treatment is $15,000 excluding GST. No detailed design or assessment of the existing hardware or underground services has been undertaken.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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DR AFT

Figure 3

2.4

Additional signs at Launceston Street

Figure 4

Sign relocation at Eggleston Crescent

Expected crash reductions

Expected crash reductions were tabulated by applying reductions available from road safety literature to the 5year crash experience in the intersection. Where crash reductions were not available through research, engineering judgement and experience were used to determine potential benefits. Only crashes of the particular type identified through literature or by engineering judgment, and on the correct approach to be affected by the option, were considered targeted crashes for reduction. The results are detailed in the “Target Crashes” and “Assumed Reduction” columns in Table 3 The low cost safety improvement option, enhanced speed limit, priority and warning signs, should reduce adjacent approach (codes 101-109) and opposing turn crashes (codes 202-206) by 5%. This treatment should reduce the likelihood of 22 of 59 total crashes that occurred during the crash history period.

2.5

Economic Analysis

The 2011 crash costs were obtained from Roads ACT to develop an economic analysis of the costs and benefits of low cost improvements. Crash cost by crash type was used for costing future crashes. When crash types were encountered that did not have indicative costs; the cost of an average property damage crash was substituted in the analysis. The present-day value of the expected costs and benefits over a 10-year project life for the option were analysed. The results are detailed in Table 3.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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Table 3

Benefit/cost analysis Hindmarsh Drive

LOCATION:

Hindmarsh Drive / Launceston St & Eggleston Crescent

Enhanced Speed Limit, Priority and Warning Signs Initial Cost of Treatment

$15,000

10

Annual Maintenance

$750

101-109

Intersection, adjacent approaches

201

Head-on

202-206

Opposing vehicles; turning

301 - 304

Rear-end Lane change

16

$35,265

$564,240

138,301

0

6

32,584

195,504

30

19,909

597,270

2

21,557

43,114

001 - 003

Vehicle hits pedestrian

163,946

706 - 707

Loss of Control (L or R turns)

82,427

401 - 402

Hit parked vehicle

21,586

601

Hit parked vehicle

23,675

501 - 506

Overtaking

28,113

901

Fell from moving vehicle

70,222

Other

5

TOTAL

59

18,096

Discounte d Benefits

Crash Description

Cost of Crashes

Crash Code

Assumed Reduction

5

Target Crashes

Years of Crash Data

Cost per Crash

7%

Total Crashes

Discount rate

Assumed Project Life

305 - 307

Low Cost Option

16

5%

$39,630

6

5%

$13,731

90,480 $1,490,608

22

$53,361

B/C Ratio

NPV

Discounted Costs

2.63

$33,094

$20,268

The benefit to cost analysis indicates that the proposed low cost safety improvement has a Benefit/Cost Ratio of 2.63. This indicates the treatment would result in over two and half times the cost of improvements returned in crash benefits.

2.6

Recommendation

The proposal for enhanced speed limit, priority and warning signs is recommended along Hindmarsh Drive at Launceston Street and Eggleston Crescent as a form of low cost improvement. Increased speed limit enforcement by both police and automated means, is also recommended. However, it should be noted that higher safety improvement could be gained with more capital expenditure (e.g.: signalising the intersections) although investigation into this type of treatment was explored in the original study.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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3.0

Melrose Drive / Theodore Street

3.1

Background

Safety improvements were made under the black spot program to the intersection of Melrose Drive and Theodore Street in late 2006. These improvements included re-alignment of the right turn and left turn entry into Theodore Street and construction of splitter Island to re-align entry into Melrose Drive. An assessment of the improvements was conducted by Roads ACT in 2010. The crash data for both the “before treatment’ and ‘after treatment’ crashes were compared. Table 4

RUM Code

Crash comparison before and after treatment Melrose Drive / Theodore Street

ACT Crash Type

Before (1/06/03 – 31/05/06) Fatal

After (1/12/06 – 30/11/09)

Injury

PDO

1

5

Total

Fatal

Change %

Injury

PDO

Total

1

14

15

150

2

2

200

5

5

66.7

2

2

200

001-003 101-109

1, 2, 4

201 202-206

1

301-304

6

305-309

3, 9

401-408

8

3

3

1

1

9

10

-100

501-506 601-609

12

701-709

19

901 Totals

1

1

23

24

140

Table 4 outlines the increase and decrease in crashes before and after the treatment specific to the crash type and severity for each crash group. Prior to treatment, the most dominant crash type was right angle collisions between vehicles from adjacent approaches (RUM 101-109). This increased by 150% after the application of treatment. Whilst the treatment eliminated manoeuvring crashes (401-408), it increased the number of right turn crashes between vehicles from opposing directions (202-206,) rear end collisions (301-304) and lane change collisions (RUM 305-309). A total increase of 140% in the number of crashes was detected at this intersection. An increase in traffic volume, especially during the peak hours was considered to be a probable factor in the increased crash rate. This caused delays at the intersection, in particular the queuing of right turn vehicles on both roads, and may have encouraged more road users to take unnecessary risks in negotiating the intersection. This may have accounted for the increase in the adjacent and opposing approach crashes, as well as the increase in rear end crashes.

3.2

Updated crash analysis

The recorded crashes were obtained from Roads ACT for the five year period from January 2007 until December 2011. The records indicate that 37 crashes have occurred at the intersection of Melrose Drive and Theodore Street. Of these crashes, 4 were injury crashes and the rest were property damage only crashes as shown in Table 5.

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11

DR AFT

Table 5

Severity

Updated crash history Melrose Drive / Theodore Street

2007

2008

2009

2010

Total

2011

Fatal

-

-

-

-

-

-

Admitted to Hospital

-

-

-

-

-

-

Received Medical Treatment

-

1

-

1

2

4

Property Damage Only

8

13

2

2

8

33

Total

8

14

2

3

10

37

In the two-year period 2010 – 2011, 13 crashes were reported at the intersection. This crash frequency is in line with the four-year count of 24 crashes in 2006 – 2009. It should also be noted that 3 injury crashes were reported in this period, an increase over the previous analysis period. A crash factor matrix has been prepared and is shown in Table 6. Almost half, 18 of 37 crashes in the 5 year period involved vehicles turning right out of Theodore Street. Most of the crashes (65%) occurred outside of peak periods.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

12

DR AFT Crash factor matrix Melrose Drive / Theodore Street

3

Theodore St 105 107

202

301

303

2011

2010

2007

2009

2

1

16

15

NB

2

2

Melrose Dr

SB

1

1

Theodore St

SB

Melrose Dr

NB

Melrose Dr

SB

Theodore St

SB

Theodore St

SB

Melrose Dr

NB

Theodore St

ES

8

104

Melrose Dr

SB

305

Melrose Dr

NB

306

Melrose Dr

NB

307

Theodore St

309

Melrose Dr Total

2

1

1

1

1

1

1

2

14

1

1

1

2

2

1

1

1

1

1

1

1

2

1

3

2

1

2

1

1

1

1

1

1

2

2

1

3

2

2 1

3

1

1

1 1

1

1

1

NB

1

1

1

NB

1

1

1

2

10

37

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2

20

2

1

30

1 1

2

2

1

2

1

2

1

13

6

1

1

10

14

1

1

1

2

1

1

2

2

1

1 2

Weekday Peak Period

1

3

1

1

1

13

1

1

1

1

Dark

NB

1

Type of Day Public Holida y Week - ends Week - days

Melrose Dr

1

Light Conditio ns Day

1

Wet

ES

Surface Dry

Theodore St

West

103

Total

South

On Street

East

DCA Code

Other Direction North

Year of Crash

Key Direct -ion

2008

Table 6

1

1 31

1

1 1

1

1

1

1

1

32

13

1 1

7

1

6

0

5


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DR AFT

3.3

Traffic characteristics

Intersection/Road geometry Melrose Drive Melrose Drive is a dual carriageway arterial road running north-south across the Woden District. It connects Yarra Glen / Yamba Drive to Athllon Drive and runs between the suburbs of Phillip, Chifley and Lyons. Melrose Drive is 6 lanes wide at its intersection with Theodore Street. The pavement width at this intersection is about 11 metres on each carriageway. Theodore Street Theodore Street is a major collector road in Curtin connecting Melrose Drive to Carruthers Street and the Curtin Shops. It is a two lane undivided road. Approaching Melrose Drive the pavement width is about 12 metres. At the intersection the road widens to accommodate parking and turn lanes, a raised concrete median and splitter island. Intersection The intersection is a seagull arrangement controlled by a ‘give way’ sign on Theodore Street. Right turn movements out of Theodore Street have a dedicated lane on Theodore Street but have no acceleration lane on Melrose Drive. Right turn movements out of Melrose Drive have a deceleration turn lane on Melrose Drive.

Figure 5

Melrose Drive/ Theodore Street

Source; ACTMAPi - ACT Government online interactive maps

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DR AFT

Traffic volume and speed The ACT Traffic Volumes 2005 – 2007 report indicates that in 2005, Melrose Drive in the vicinity of Theodore Street was travelled by approximately 11,000 vehicles in each direction each weekday; with about 1,400 heading north in the AM peak hour, and 1,400 heading south in the PM peak hour. The sign-posted speed limits on the roads approaching the intersection are as follows: - 70 km/h on Melrose Drive - 60 km/h on Theodore Street Public transport Many ACTION weekday bus services travel through the intersection, going to and from the Woden Bus Interchange. Melrose Drive carries routes 21, 22, all Blue Rapid 300 series and several Xpresso routes. Theodore Street carries route 2, 76, 77, 932, and 732. There are bus stops on each side of Melrose Drive, just south of the intersection as shown in Figure 6. These bus stops are among the busiest non-interchange bus stops in the ACT, with gaps between buses well under five minutes in peak hours. It is not unusual to see two or three buses stopping in the northbound stop. There is also a bike parking cage for Bike and Ride customers.

Figure 6

ACTION Weekday Bus Service

Bicycles and Pedestrians On road cycle lanes and a shared use path are provided on Melrose Drive. Foot paths are provided on both Theodore Street and Melrose Drive as shown in Figure 3 below. There is also a Bike and Ride bicycle cage adjacent to the City-bound bus stop.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

DR AFT

Figure 7

Legend:

ACT Walking and Cycling Map: Melrose Drive / Theodore Street detail

On road Cycle Lane,

Shared Path,

Foot path

Land Use There is no direct property access on Melrose Drive. Theodore Street provides direct access to residential properties.

3.4

Site inspection

A weekday site inspection was undertaken on Tuesday, 3 July 2012 at 10:30 AM. The following observations were noted: -

The majority of turning movements at the intersection are right turn movements out of Theodore Street to Melrose Drive.

-

Many cars turning right on Melrose Drive quickly moved left to turn left at Launceston Street.

-

The intersection warning sign for pedestrians and bicycle riders (on side road) on Melrose Drive when turning into Theodore Street is confusing and can be misunderstood.

-

Sight distance is adequate at the intersection.

-

A waiting queue on the right turn movement out of Theodore Street was observed.

-

There was little to no queuing on the left turn movement out of Theodore Street.

-

Drivers turning right into and out of Theodore Street may misjudge the gap crossing three lanes which are travelling at 70 km/h.

-

It was also noted that there was no formal pedestrian crossing on Melrose Drive.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

16

DR AFT

Queuing on the right turn movement out of Theodore Street onto Melrose Drive.

No formal pedestrian facilities for crossing Melrose Drive at Theodore Street

Intersection ‘On side road’ warning sign for pedestrians and bicycle riders may be misunderstood.

The left turn out of Theodore Street was not very heavy at 10:30 am.

3.5

Remedial measures

Several scenarios were considered at this location. The greatest crash reduction would probably come from installing traffic signals at this intersection, however this would be outside the scope of low cost safety measures, so were not investigated any further. Banning the right turn out of Theodore Street, particularly in the morning, would reduce the likelihood of crashes; however, this would have to be studied separately as it would impact other intersections within the network. A third scheme was considered, which involved extending the bus lane through the intersection at Theodore Street. This would require merging the left and centre lanes of Melrose Drive south of the bus stop, and may impact the intersection of Melrose Drive and Launceston Street. This was dismissed due to the potential capacity reduction and unintended safety impacts at the intersection and merge point. The proposed remedial measure for this intersection is enhancing intersection conspicuity with dual intersection warning signs on Melrose Drive, and marking the intersection on northbound Melrose Drive with a ‘Keep Clear’ box. The intersection warning signs will remind drivers that turn movements may be occurring ahead. One sign is mounted in the median as the road is quite wide here, and warnings in the verge may be missed or obscured by vehicles in the bus stop. The keep clear marking will give drivers turning out of Theodore Street a wider field of vision to check for oncoming traffic.

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DR AFT

Figure 8

Low-Cost Safety Option for Melrose Drive / Theodore Street

The estimate of probable cost to install this treatment is $15,000 excluding GST. No detailed design or assessment of the existing hardware or underground services has been undertaken.

3.6

Expected crash reductions

Expected crash reductions were tabulated by applying reductions available from road safety literature to the 5year crash experience in the intersection. Where crash reductions were not available through research, engineering judgement and experience were used to determine potential benefits. Only crashes of the particular type identified through literature or by engineering judgment, and on the correct approach to be affected by the option, were considered targeted crashes for reduction. The results are detailed in the “Target Crashes” and “Assumed Reduction” columns in Table 7. The low cost safety improvement option, intersection warning signs and keep clear marking, should reduce adjacent approach (codes 101-109) and opposing turn crashes (codes 202-206) by 5%. This treatment should reduce 23 of 37 total crashes that occurred during the crash history period.

3.7

Economic analysis

Crash costs for 2011 were obtained from Roads ACT to develop an economic analysis of the costs and benefits of low cost improvements. Crash costs by crash type were used for costing future crashes. When crash types were encountered that did not have indicative costs; the cost of an average property damage crash was substituted in the analysis. The present-day value of the expected costs and benefits over a 10-year project life for the option were analysed. The results are detailed in Table 7.

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18

DR AFT

Table 7

Benefit/cost analysis Melrose Drive / Theodore Street

LOCATION:

Melrose Drive / Theodore Street

OPTION 1

$750

Crash Code

Crash Description

101-109

Intersection, adjacent approaches

201

Head-on

202-206

Opposing vehicles; turning

3

301 - 304

Rear-end Lane change

22

$35,265

Discounte d Benefits

10

Assumed Reduction

$15,000

Annual Maintenance Target Crashes

Initial Cost of Treatment

Cost of Crashes

5

Cost per Crash

Years of Crash Data

Total Crashes

7%

Assumed Project Life

305 - 307

Intersection warning signs and a keep clear box.

Discount rate

$775,830

20

5%

$49,537

32,584

97,752

3

5%

$6,866

8

19,909

159,272

3

21,557

64,671

138,301

001 - 003

Vehicle hits pedestrian

163,946

706 - 707

Loss of Control (L or R turns)

82,427

401 - 402

Hit parked vehicle

21,586

601

Hit parked vehicle

23,675

501 - 506

Overtaking

28,113

901

Fell from moving vehicle

70,222

Other

1

TOTAL

37

18,096

18,096 $1,115,621

23

$56,403

B/C Ratio

NPV

Discounted Costs

2.78

$36,135

$20,268

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

19

DR AFT

The benefit to cost analysis indicates that the proposed low cost safety improvement has a Benefit/Cost Ratio of 2.78. This indicates the treatment would result in over two and half times the cost of improvements returned in crash benefits.

3.8

Recommendation

The proposal for Intersection warning signs and a ‘keep clear’ is recommended on Melrose Drive as a form of low cost improvement. However, it should be noted that higher safety improvement could be gained with more capital expenditure (e.g.: signalising the intersection) although investigation into this type of treatment was not explored in this study.

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DR AFT

4.0

Wentworth Avenue / Mildura Street / Leichhardt Street

4.1

Background

Safety improvements were made in 2007 under the black spot program to the intersection of Wentworth Avenue, Mildura Street and Leichhardt Street. The improvements included installation of traffic islands, signs and line marking. An assessment of the improvements was conducted by Roads ACT in 2010. The crash data for both the “before treatment’ and ‘after treatment’ crashes were compared. Table 8

RUM Code

Crash comparison before and after treatment Wentworth Avenue / Mildura Street / Leichhardt Street

ACT Crash Type

Before (1/03/04 – 28/02/07) Fatal

After (1/10/07 – 30/09/10)

Injury

PDO

Total

Fatal

5

6

11

1

Injury

Change %

PDO

Total

7

8

-27.3

1

1

100.0

1

1

0

001-003 101-109

1, 2

201

5

202-206

1

301-304

6

305-309

3, 9

1

1

100.0

401-408

8

2

2

200.0

501-506

9

12

13

8.3

1

1

601-609 701-709

19

901 Totals

5

7

12

1

Table 8 outlines increase and decrease in crashes before and after the treatment specific to the crash type and severity for each crash group. The most dominant crash type before the treatment was due to collisions between vehicles from adjacent approaches (RUM 101-109). After black spot improvements, the total number of these crashes was reduced by 27%. However, there was one fatal adjacent approach crash in the after study period. Opposing turn collisions (RUM 202-206), lane side swipes (RUM 305-309) and manoeuvring crashes (RUM 401-408) all increased. An overall 8% increase in the total number of crashes was detected at this intersection after the treatment. The modifications done to this intersection was not found to be cost effective as it had increased the number of crashes by 8% and given a savings of only $ 1,596 in crash costs per annum.

4.2

Crash analysis

The recorded crashes were obtained from Roads ACT for the five year period from January 2007 through December 2011. These crashes were reviewed to identify any crash patterns and trends and also assist in the understanding of the contributory causes of the crashes. The records indicate that 16 crashes have occurred at the intersection of Melrose Drive and Theodore Street. Of these crashes, 1 was a fatal crash and the rest were property damage only crashes as shown in Table 9.

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DR AFT

Table 9

Severity

Updated crash history Wentworth Avenue / Mildura Street / Leichhardt Street

2007

2008

Fatal

2009

2010

Total

2011

1

1

Admitted to Hospital Received Medical Treatment Property Damage Only

3

4

5

1

2

15

Total

3

5

5

1

2

16

In 2011, 2 crashes were reported at the intersection. This crash frequency represents a significant decrease from the 3.5 per annum crash rate of the previously studied 2007 – 2010 period. Crashes were well distributed among types; however, 9 of 16 were right angle crashes from adjacent approaches. A crash factor matrix has been prepared and is shown in Table 10.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

22

DRAFT Crash factor matrix Wentworth Avenue / Mildura Street / Leichhardt Street

102

104

WB

1

Mildura St.

WB

Wentworth Av.

SB

2011

2010

2009

2008

1

1

2

1

1

1

1

1

1

1

301

Wentworth Av.

NB

1

1

308

Wentworth Av.

NB

1

1

404

Mildura St.

NB

1

2

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2

16

1

2

2

4

1

1

1

1 1 1

1

3

1

1

1

1

1

2

2

2

8

14

2

Weekday Peak Period

1

1

1

1

1

1

NB

1

1

1

Wentworth Av.

1 1

2

1

202

5

1

1

1

5

3

1

SB

3

4

1

Mildura St.

Total

3

1 1

1

2

Week - days

Wentworth Av.

4

2

Week - ends

1

2

Type of Day Public Holiday

1

2

Dark

SB

2

Day

Mildura St.

2

2

Wet

SB

Light Conditions

Dry

Wentworth Av.

Total

South

Key Direction

Surface

West

101

On Street

2007

DCA Code

Other Direction

East

Year of Crash

North

Table 10

11

1

4

11

3


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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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DR AFT

4.3

Traffic characteristics

Intersection/Road Geometry

Figure 9

ACTMAPi aerial view of Wentworth Avenue / Mildura Street / Leichhardt Street

Wentworth Avenue Wentworth Avenue is an arterial road running northwest -southeast across Kingston suburb of the ACT. It is a 4 lane divided carriage way separated by a 32 m median at its intersection with Leichhardt Street/ Mildura Street. The pavement width at its intersection with Leichhardt Street is about 9 metres in the northbound direction and 5.5 metres in the southbound direction.

Leichhardt Street Leichhardt Street is a major collector road in the suburbs of Kingston and Griffith connecting Wentworth Avenue to Giles Street. It is a two lane undivided road. At its intersection with Wentworth Avenue the pavement width is about 8 metres. Mildura Street Mildura Street is a major collector road in the suburb of Fyshwick connecting Wentworth Avenue to Canberra Avenue. It is a two way undivided road. At its intersection with Wentworth Avenue the pavement width is about 11.4 metres.

Traffic volume and speed The ACT Traffic Volumes 2005 – 2007 report indicates that in August, 2007, the segment of Wentworth Avenue between Hely Street and Hume Circle (one block east of the intersection) carried approximately 20,000 vehicles on each weekday; with about 1,300 travelling toward the subject intersection in the AM peak hour, and 1,100 travelling away from the intersection in the PM peak hour.

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DR AFT

The sign-posted speed limits on the roads approaching the intersection are as follows: 60 km/h on Wentworth Avenue 50 km/h on Mildura Street 50 km/h on Leichhardt Street Public transport Wentworth Avenue carries the Red Rapid 200 service and several Xpresso services. Mildura Street carries route 80 weekday service and 980 weekend service; however current routing does not go through the intersection. There are no bus stops located near the intersection.

Figure 10

ACTION Weekday Bus Service

Bicycles and Pedestrians On road cycle lanes and a shared use path are provided on Wentworth Avenue. Foot paths are provided on both Leichhardt Street and Mildura as shown in Figure 11 below.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

DR AFT

Figure 11

ACT Walking and Cycling Map: Wentworth Avenue detail

Legend:

On road cycle lane,

shared path,

foot path

Land Use There is no direct property access on Wentworth Avenue. Leichhardt Street and Mildura Street provide direct access to commercial properties, including the railway station and the Capitol Chilled Foods facility.

4.4

Site inspection

A weekday site inspection was undertaken on Tuesday, 10 July 2012 at 2:30 pm. The following observations were noted: The intersection can be difficult to perceive when coming from the west on Wentworth Avenue. Give Way signs at the intersection can be replaced with Stop signs in order to improve intersection crossing and reinforce priority. The One Way sign post that was seemingly located at the intersection of Wentworth Avenue/ Mildura Street was uprooted which left a hole on the side of the road by the pedestrian shared path. Motorists may be confused about priority when through and turning vehicles leaving the median conflict with through and turning vehicles leaving the side roads. The bicycle warning sign on Mildura Street approaching Wentworth Avenue is may not be perceived properly by some drivers.

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AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

26

DR AFT

Uprooted One Way sign post by the side of the road

Unclear bicycle warning sign on Mildura Street.

4.5

One Give Way sign on the Mildura Street east approach

Remedial measures

Converting the median Give Way signs to Stop signs was considered because drivers may have difficulty looking to their left when leaving the median. However the sight lines at the intersection appear to be adequate, and the Australian Standard AS 1742.2 explicitly discourages installation of Stop signs solely due to crash history. The recommended low cost safety improvements at the intersection of Wentworth Avenue, Mildura Street and Leichhardt Street include: -

Reposition existing Give Way sign on Mildura Street closer to intersection

-

Supply additional Give Way sign on the median island on Mildura Street

-

Refresh paint and install Reflective Pavement Markers (RPM) for all median crosshatching in intersection (see Figure 12).

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DR AFT

Figure 12

Low Cost Safety Improvements Wentworth Avenue / Mildura Street / Leichhardt Street

The estimate of probable cost to install this treatment is $15,000 excluding GST. No detailed design or assessment of the existing hardware or underground services has been undertaken.

4.6

Expected crash reductions

Expected crash reductions were tabulated by applying reductions available from road safety literature to the 5year crash experience in the intersection. Where crash reductions were not available through research, engineering judgement and experience were used to determine potential benefits. Only crashes of the particular type identified through literature or by engineering judgment, and on the correct approach to be affected by the option, were considered targeted crashes for reduction. The results are detailed in the “Target Crashes” and “Assumed Reduction” columns in Table 7. The low cost safety improvement option, intersection warning signs and keep clear marking, should reduce adjacent approach (codes 101-109) by 5%. This treatment should reduce the likelihood of 11 of 16 total crashes that occurred during the crash history period.

4.7

Economic analysis

Crash costs for 2011 were obtained from Roads ACT to develop an economic analysis of the costs and benefits of low cost improvements. Crash costs by crash type were used for costing future crashes. When crash types were encountered that did not have indicative costs; the cost of an average property damage crash was substituted in the analysis. The present-day value of the expected costs and benefits over a 10-year project life for the option were analysed. The results are detailed in Table 11.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

28

DR AFT

Table 11

Benefit/cost analysis Wentworth Avenue / Mildura Street / Leichhardt Street

LOCATION:

Wentworth Ave / Mildura St / Leichhardt St

OPTION Restripe Mildura Island, reposition Give Way signs, RPMs in median

5

Initial Cost of Treatment

$15,000

10

Annual Maintenance

$750

Cost per Crash

11

$35,265

$387,915

138,301

0

1

32,584

32,584

1

19,909

19,909

Lane change

21,557

0

001 - 003

Vehicle hits pedestrian

163,946

0

706 - 707

Loss of Control (L or R turns)

82,427

0

401 - 402

Hit parked vehicle

21,586

0

601

Hit parked vehicle

23,675

0

501 - 506

Overtaking

28,113

0

901

Fell from moving vehicle

70,222

0

18,096

54,288

Crash Code

Crash Description

101-109

Intersection, adjacent approaches

201

Head-on

202-206

Opposing vehicles; turning

301 - 304

Rear-end

305 - 307

Other

3

TOTAL

16

Cost of Crashes

Total Crashes

Assumed Project Life

$484,696

11

5%

11

Discounte d Benefits

Years of Crash Data

Assumed Reduction

7%

Target Crashes

Discount rate

$27,246

$27,246

B/C Ratio

NPV

Discounted Costs

1.34

$6,978

$20,268

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AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

29

DR AFT

The benefit to cost analysis indicates that the proposed low cost safety improvement has a Benefit/Cost Ratio of 1.34. This indicates the treatment would result in a crash reduction value only slightly greater than installation and maintenance costs.

4.8

Existing deficiencies and maintenance items

The uprooted One Way sign at the northeast corner should be reinstalled.

4.9

Recommendation

Despite not meeting the desired ratio of benefits outweighing costs by a factor of two, the low cost safety improvements at Wentworth Avenue and Mildura Street / Leichhardt Street may still be considered for their ability to improve safety at the intersection. If the restriping of the approach islands and raised pavement markers are not initially installed, replacement of a second Give Way sign on the median of Mildura Street should be considered as a maintenance item. Should the crash record continue to increase in the future, consideration should be given to a more substantial upgrade to the intersection.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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DR AFT

5.0

Kuringa Drive

5.1

Background

Safety improvements were made under the black spot program to the mid-block section of Kuringa Drive between Tillyard Drive and Kingsford Smith Drive in June 2008. These improvements included Installation of warning signs, guardrails and lighting. An assessment of the improvements was conducted by Roads ACT in 2011. The crash data for both the “before treatment’ and ‘after treatment’ crashes were compared. Table 12

Crash comparison before and after treatment Kuringa Drive

Before (1/03/05 – 28/02/08)

After (1/10/08 – 30/09/11)

Change %

RUM Code Fatal

Injury

PDO

Total

2

2

Fatal

Injury

PDO

Total

001-003 101-109 201 202-206 301-304

-100.0

305-309

1

1

+100.0

1

1

0

1

2

3

-66.7

401-408 501-506 601-609 701-709

1

801-805 Totals

1

1

1

8

9

4

4

1

7

11

19

+375.0

15

16

1

8

15

24

+50.0

Table 12 outlines the increase and decrease in crashes before and after the treatment specific to the crash type and severity for each crash group. Prior to treatment, the most frequent crash type was single vehicle off path on straight (RUM 701-709). This fell by 66.7% after the application of treatment, and off path on curve (RUM 801-805) crashes increased by 375%. A total increase of 50% in the number of crashes was detected on this midblock section. It was considered that continued speeding on the road may have been responsible for the continued crashes.

5.2

Updated crash analysis

The recorded crashes were obtained from Roads ACT for the five year period from January 2007 through December 2011. The four years since safety treatments were installed (2009 – 2011) were analysed. The records indicate that 23 crashes occurred on Kuringa Drive in this period. These crashes include one fatality, 8 injury crashes, and 14 property damage crashes as shown in Table 13.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

31

DR AFT

Table 13

Severity Fatal

Updated crash history Kuringa Drive

2009

2010

Total

2011

1

Admitted to Hospital

1 2

1

3

Received Medical Treatment

1

4

5

Property Damage Only

4

6

4

14

Total

6

12

5

23

The crash frequency is almost 8 crashes per year. An increase over the five crashes per year in the period studied before the treatment was installed. This period contained nine injury or fatal crashes compared to one injury crash in the previous analysis period. The most common crash types were single vehicles leaving the roadway. Nineteen of 23 (85%), were RUM Code 8xx, “off path on curve” crashes. Two more were code 7xx, “off path on straight”. The bulk of the crashes, 20 of 23, occurred in the westbound direction. Twelve of 23 crashes were on wet roads, and one involved snow or ice. Only one crash occurred during the weekday peak traffic periods. Fourteen (61%) occurred on a weekend or public holiday. A crash factor matrix is shown in Table 14.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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DR AFT Crash factor matrix for Kuringa Drive

On Street

307

Kuringa Drive

WB

609

Kuringa Drive

WB

703

Kuringa Drive

WB

1

1

704

Kuringa Drive

WB

1

1

Kuringa Drive

WB

2

2

Kuringa Drive

EB

1

1

2

Kuringa Drive

WB

1

2

Kuringa Drive

WB

2

Kuringa Drive

EB

804

Kuringa Drive

WB

3

805

Kuringa Drive

WB

3 12

801 802 803

Total

1 1

1

6

1

1

1

1

Wet*

Dry

2011

2010

Total

1

Type of Day

1 1

1

1

1

1

1 1

1

2

1

1

2

1

1

1

1

1

3

3

2

1

1

1

1

2

2

1

1

1

1

1

1

1

1

1

3

1

2

2

1

2

1

3

6

5

1

5

1

2

4

5

23

10

13

14

9

11

9

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Weekday Peak Period

Public Holida y Week - ends Week - days

DCA Code

Light Conditio ns Dark

Surface

Day

Year of Crash

Key Direct -ion

2009

Table 14

3

1

1


AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

33

DR AFT

5.3

Traffic characteristics

Road geometry Kuringa Drive is a two lane arterial road connecting the north Belconnen suburbs of Fraser and Spence to the Barton Highway. With the extension of Clarrie Hermes Dive, Kuringa Drive also provides access to Nicholls and Ngunnawal in Gungahlin. The pavement width is about 6.4 metres widening slightly at curves. There are three curved sections: a very sharp curve at Tillyard Drive, back to back curves about midway to Kingsford Smith Drive, and a curve just west of Kingsford Smith Drive. The curves are posted with advisory speed warning signs at 35, 45 and 55 km/h.

Kuringa Drive

Figure 13

Kuringa Drive Source: Google Earth Pro

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

DR AFT

Figure 14

Kuringa Drive / Tillyard Drive Curve Source: ACTMAPi

Figure 15

Kuringa Drive back-to-back curves Source: ACTMAPi

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AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

35

DR AFT

Figure 16

Kuringa Drive / Kingsford Smith Drive Source: ACTMAPi

Land use There is no residential frontage along the road. The only property access on the road is a driveway approximately 400 m west of Kingsford Smith Drive which provides access (through a locked gate) to the rural blocks to the north. Traffic volume and speed The ACT Traffic Volumes 2005 – 2007 report indicates that in 2007, Kuringa Drive between Barton Highway and Owen Dixon Drive was travelled by approximately 11,000 vehicles each weekday. This gives an indication of the volume of traffic in the study area. Traffic volumes may have risen in recent years with development in northern and western Belconnen. Volumes will likely rise again with the recent opening of the Clarrie Hermes Drive extension at the signalise intersection of Barton Highway and Kuringa Drive. The sign-posted speed limits on Kuringa Drive are as follows: -

80 km/h from Barton Highway to Owen Dixon Drive 70 km/h from Owen Dixon to Kingsford Smith Drive 60km/h from Kingsford Smith Drive to Tillyard Drive

Public transport There are no ACTION bus services on Kuringa Drive. Weekday bus services stop nearby on Tillyard Drive (314) and Kingsford Smith Drive (315). There are similar weekend and Xpresso (peak hour) services. The weekday bus services are depicted in Figure 17.

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

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DR AFT

Figure 17

ACTION Weekday Bus Service

Bicycles and Pedestrians There are no bicycle or pedestrian facilities on this section of Kuringa Drive. Nearby foot paths and shared paths are depicted in Figure 18.

Figure 18

Legend:

ACT Walking and Cycling Map: Kuringa Drive detail

On road Cycle Lane,

Shared Path,

Foot path

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

37

DR AFT

5.4

Site inspection

A weekday site inspection was undertaken on Monday, 15 October 2012 at 2:00 PM. The following observations were noted: -

The road presents a long (1.5 kilometres) stretch of asphalt without intersections or turn offs

-

Pavement width appears adequate, however, there are no paved shoulders, and soft shoulders are often overgrown or in poor condition

-

There is little superelevation through curves

-

Several signs are missing, and many are overgrown

-

Asphalt condition is adequate, markings are clear and raised pavement markers are plentiful

-

Several guide posts are missing or damaged

-

“Reduce Speed Now� signs are conspicuous, however some are obscured by trees

-

Curve warning and advisor speed signs are standard size and mounting

-

In the middle of the afternoon, traffic was steady in both directions, and vehicles were not platooned Drivers travelled the road at differing speeds. Some were very cautious and adhered to speed limits and advisory speeds, others exceeded speed limits

-

Vehicle skid marks were noted on the westbound lane, possibly indicating an eastbound driver who lost control and crossed the oncoming lane before leaving the roadway

Shoulder erosion westbound in back-to-back curves

Unmarked and unprotected culvert headwall westbound

Overgrown signage

Damaged guide post

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

38

DR AFT

Reduce speed sign and curve warning sign westbound

Damaged speed limit sign eastound near Tillyard Drive

Overgrown curve warning sign eastbound

Missing curve warning sign eastbound

“Reduce Speed Now” sign obscurred

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

39

DR AFT

5.5

Remedial measures

The proposed remedial measures for this midblock road section are: -

Improve speed limit signage with larger signs at the beginning of the road segment and repeater signs along the road. To highlight the change in speed limit on the approach form the west, the speed limit should be marked in the westbound lane after Kingsford Smith Drive.

-

Enhance curve warning and advisory speed signs by installing on both sides of the road leading into the back to back curve and repeating curve warning signs on both sides of the road in between back to back curves. The missing curve warning sign eastbound should be replaced.

-

Increase supply of retro-reflective raised pavement markers (RRPMs) by halving spacing along the centreline and edge lines approaching and through all signposted curves.

Figure 19

Tillyard Street curve detail for RRPM treatment extents

Figure 20

Back to back curve detail for RRPM treatment extents

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

DR AFT

Figure 21

Kingsford Smith Drive curve detail for RRPM treatment extents

Figure 22

Enhanced speed limit marking on Kuringa Drive

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AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

DR AFT

Figure 23

Enhanced curve warning and speed signs on Kuringa Drive

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AECOM

Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

42

DR AFT

The estimate of probable cost to install this treatment is $15,000 excluding GST. No detailed design or assessment of the existing hardware or underground services has been undertaken.

5.6

Expected crash reductions

Expected crash reductions were tabulated by applying reductions available from road safety literature to the 5year crash experience in the intersection. Where crash reductions were not available through research, engineering judgement and experience were used to determine potential benefits. Only crashes of the particular type identified through literature or by engineering judgment, and on the correct approach to be affected by the option, were considered targeted crashes for reduction. The results are detailed in the “Target Crashes” and “Assumed Reduction” columns in Table 7. The low cost safety improvement options—enhanced speed limit signs and marking, curve warning signs and retro-reflective raised pavement markers—should reduce “Other” crashes by 10%. Other crashes include primarily RUM code 703 – 704 off path on straight and 801 – 805 off path on curve crashes. This treatment should reduce the likelihood of 22 of 23 total crashes that occurred during the crash history period.

5.7

Economic analysis

Crash costs for 2011 were obtained from Roads ACT to develop an economic analysis of the costs and benefits of low cost improvements. Crash costs by crash type were used for costing future crashes. When crash types were encountered that did not have indicative costs; the cost of an average property damage crash was substituted in the analysis. It should be noted that crash costs were not provided for “Other” crashes such as off path on straight and off path on curve. Following methodology employed in previous safety and black spot studies, the cost of a property damage crash was substituted for these values. However, actual crash costs may be greater than this aggregate value. This may cause the benefit cost analysis to understate the benefits of a given treatment. The present-day value of the expected costs and benefits over a 10-year project life for the option were analysed. The results are detailed in Table 11. .

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43

DR AFT

Table 15

Benefit/cost analysis Kuringa Drive

LOCATION:

Kuringa Drive (Tillyard Street to Kingsford Smith Drive

LOW COST OPTION Enhanced speed limit signs and marking, curve warning signs and RRPMs

10

$750

Assumed Project Life

Crash Code

Crash Description

101-109

Intersection, adjacent approaches

$35,265

201

Head-on

138,301

202-206

Opposing vehicles; turning

32,584

301 - 304

Rear-end

305 - 307

Lane change

21,557

001 - 003

Vehicle hits pedestrian

163,946

706 - 707

Loss of Control (L or R turns)

82,427

401 - 402

Hit parked vehicle

21,586

601

Hit parked vehicle

23,675

501 - 506

Overtaking

28,113

901

Fell from moving vehicle

70,222

1

Other

22

TOTAL

23

19,909

18,096 $418,021

Discounte d Benefits

$15,000

Annual Maintenance Assumed Reduction

Initial Cost of Treatment

Target Crashes

3

Cost of Crashes

Years of Crash Data

Cost per Crash

7%

Total Crashes

Discount rate

19,909

398,112

22

$418,021

22

10%

$93,206 $93,206

B/C Ratio

NPV

Discounted Costs

4.60

$72,938

$20,268

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Low Cost Safety Improvements Low Cost Safety Improvements - Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive

44

DR AFT

The benefit to cost analysis indicates that the proposed low cost safety improvement has a Benefit/Cost Ratio of 4.60. This indicates the treatment would result in a crash reduction value four times greater than installation and maintenance costs.

5.8

Existing deficiencies and maintenance items

Overgrown trees, particularly those obscuring warning signs should be cut back. Missing and damaged signs should be replaced. The eroded shoulder in the westbound lane in the back to back curves should be repaired. Guide posts in the verge and marking hazards should be reviewed and repaired throughout the road length and particularly in the back to back curves.

5.9

Recommendation

The proposal for enhanced speed limit signs and marking, curve warning signs and retro-reflective raised pavement markers is recommended for the mid-block section of Kuringa Drive between Tillyard Street and Kingsford Smith Drive as a form of low cost improvement. However, it should be noted that higher safety improvement could be gained with more capital expenditure (e.g. realignment) although investigation into this type of treatment was not explored in this study. The existing deficiencies identified in Section 5.8 should be addressed as part of regular maintenance. It should be noted that this form of treatment relies on a high level of driver compliance. As such, this location should be considered for increased speed enforcement. Extra attention should be given in the back to back curves. This enforcement should be focused on the westbound traffic, particularly on straight segments and in the back to back turns. Both police speed enforcement and automated speed enforcement means should be considered.

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Low Cost Safety Improvements Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive  

Low Cost Safety Improvements Hindmarsh Drive, Melrose Drive, Wentworth Avenue & Kuringa Drive - ACT Roads 27th November 2012

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