This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.
Project Description: The Proposed Treatment Includes The Following Components:
Install mast arms at both westbound approaches of Flinders St/William St and Flinders/Market St; • Install additional LED “No Right Turn” signs at three locations: William Street / Flinders Street on the bridge viaduct pillar for southbound traffic, William Street in the median just north of Flinders Street for southbound traffic & Market Street / Flinders Street on Flinders Street for westbound traffic • Install additional advance warning signs of the right turn ban in William Street for southbound traffic before the Flinders Lane intersection. • Provide an extra 3 aspect lantern fitted with louvers for east bound right turning traffic on the northern centre median, such that the lantern can only be seen by the East bound traffic lanes. • Existing lantern on the northern centre median facing northbound traffic to be fitted with louvers and redirected, such that the lantern can only be seen by the North/West bound traffic lanes.
William Street / Flinders Street / Queensbridge Road is a major cross road intersection on the edge of the Melbourne CBD. All three roads are local roads that function as arterials roads. Queensbridge Street provides one of the major access points over the Yarra River and as such provides a critical link from Southbank to Melbourne. Queensbridge Street's layout however, includes a sharp reverse curve to line up with William Street. This reverse curve is also required due to the proximity of the railway viaduct which runs parallel to and immediately south of Flinders Street at this location. The railway viaduct is very close to Flinders Street at William Street with its pillars located approximately 1m behind the kerb of Flinders Street. The pillars spacing dictates the traffic lanes and the layout of the southern approach of the intersection. Queensbridge Street has 2 southbound through lanes, 2 northbound right turn lanes and 2 northbound through and a northbound left turn lane in the 3 spans of the railway viaduct at this location. All turn movements are permitted for the northbound approach.
Flinders Street forms the east - west route on the southern boundary of the Melbourne CBD. At this location it has 2 through lanes in each direction and an eastbound right turning lane. It also has tram tracks in the centre carriageway, however there are no tram stops in the vicinity of the William Street intersection. The westbound right turn movement is banned. William Street forms the northern leg of this intersection. It approaches the intersection as a dual carriageway road with 2 traffic lanes in either direction. Southbound traffic is banned from turning right with “No Right Turn” signs at the intersection including a LED “No Right Turn” sign.
Three road safety cameras exist at this intersection for the southern and eastern legs of the intersection, capturing all westbound traffic and the northbound through and northbound right turning traffic. There are significant pedestrian movements, with pedestrian walkways across all legs of the intersection, except the eastern leg. The eastern leg is quite close (65m) to the Market Street / Flinders Street intersection and there are pedestrian walkways on all legs of the Market Street intersection. Given the close proximity of the Market Street intersection and its combined function of accessing Queensbridge Street, this intersection also forms part of this proposal.
Crash History (William Street / Flinders Street Intersection)
There have been 46 casualty crashes in the five year period 1/7/2002 - 30/6/2007 (most recent 5 year crash period currently available) at the William Street / Flinders Street intersection.
These crashes have been analysed and two major trends have been identified; - 12/46 (26%) crashes involve southbound right turning / right through type crashes (DCA121) although the southbound right turn movement is banned; - 21/46 (46%) crashes are cross traffic type crashes involving north and westbound vehicles (DCA 110 and 113).
Right Through (DCA 121 Trend) This trend involves southbound right turning vehicles colliding with oncoming northbound traffic. There are a total of 12 of these type crashes. Key trends observed are; - 3/12 occurred in wet conditions; - 3/12 were higher severity crashes (SI or F); - 5/12 occurred after dark; - 5/12 occurred around lunch time; - 6/12 occurred on a weekend.
It should be noted that a LED right turn ban sign was commissioned in December 2005. It would appear that LED sign has contributed in the reduction of motorists conducting the banned manoeuvre, however according to crash data motorists are still illegally turning right. The BCR calculation for this proposal does not include the right turn crashes prior to commissioning of the LED right turn ban sign.
Scope Approval Report Flinders Street / William Street
Cross Traffic (DCA 110 / 113 Trend) This trend involves westbound through vehicles colliding with northbound traffic (either through or right turning). There are a total of 21 of these type of crashes with a significant proportion of these identified in the police reports as running a red light. Key trends observed are; - 9/21 were the result of a westbound vehicle running a red light; - 3/21 were the result of a northbound vehicle running a red light; - 9/21 were higher severity crashes (SI or F); - 12/21 occurred on weekends; - 10/21 occurred at night; - 5/21 occurred in twilight conditions - all at dawn (sun behind the westbound driver).
The southern approach of the Flinders Street / William Street intersection is divided by a railway viaduct, with right turn traffic on one side and through/left traffic on the other. The sequence of the southern approach in the fully controlled mode is that through and right traffic is allowed to flow simultaneously, until such time the right turn arrow changes back to red. It has been identified that the lantern located in the northern centre median facing the southern approach should be redirected to face only the through/left lanes and that the lantern be fitted with a vertical louvers to complement the treatment. Furthermore, an extra lantern also fitted with louvers facing the right turn lanes should be installed to provide clarity to motorists when filtering through the intersection.
Of the two major trends, the one with illegal southbound right turning vehicles stands out as one that should not be occurring. The southbound right turn movement is a banned movement, most likely due to inappropriate sight lines to approaching traffic under the viaduct. The pillars are solid brick and provide a substantial impediment for sight lines.
With the other trend (cross traffic), the key issue for this trend is possibly attributed to westbound traffic queuing through this intersection from the Flinders Street / King Street Intersection. The westbound vehicles in the intersection try to stop in the lee of the viaduct pillars, however, their sight line to northbound traffic is also obstructed due to the viaduct pillars when they move forward.
This intersection is unusual for a Flinders Street signalized intersection in the CBD in that it does not have queue detector loops on the departure side of the intersection for westbound traffic. This is most likely due to when the King Street overpass was in place and westbound traffic did not queue this far east from the Spencer Street intersection. However with the removal of the King Street overpass, Flinders Street westbound traffic now seems to regularly queue through the intersection.
The sight lines (to either side) for northbound traffic are obstructed due to the viaduct. This “blind” start is likely to be a major contributing factor for this crash trend at this location.
The Market Street / Flinders Street / Queensbridge Street intersection has some unique operating parameters. Market Street is a relatively low volume local road and forms the northern leg of this intersection. Southbound traffic on this approach utilizes a single lane and must turn right or left with through southbound traffic banned, with the exception of trams which proceed south on a tram only reservation on the south side of the intersection. Queensbridge Street forms the southern leg of this intersection. It essentially has 2 parts with southbound traffic comprising only of westbound left turning traffic. The northbound component is made up only of trams and Met buses. All other northbound traffic is deflected to the William Street intersection.
Flinders Street at the Market Street intersection has both east and westbound right turn movements banned. Tram stops are located on the eastern leg of this intersection. The crashes at the Market Street / Flinders Street intersection considered relevant to the trends (and treatments yet to be discussed) at the William Street / Flinders Street intersection are; - 12/13 crashes at the Market Street intersection involved a westbound vehicle (ties into the large number of westbound vehicles involved in the cross traffic type crashes at William Street); - 3 involved a westbound vehicle attempting the banned right turn movement (similar to the large number of illegal right through type crashes at William Street).
Scope Approval Report Flinders Street / William Street
One of the proposed treatments for the William Street / Flinders Street intersection is the provision of mast arms for westbound traffic. Given the close proximity (65m) to the Market Street / Flinders Street intersection, provision of mast arms would likely introduce a westbound “see through” effect at the Market Street intersection. The improvement of the William Street intersection needs to be extended to the Market Street intersection to maintain consistency and not “shift” or create safety issues at the Market Street intersection. Accordingly, a mast arm installation is also proposed at Market Street to Face west bound traffic.
The eastbound right turn facility at the William Street intersection has a partially fully controlled right turn phase. The right turn is fully controlled off peak and at peak the right turners filter through the intersection. VicRoads' Network Operations advised that clarity issues associated with the eastbound right turn lane signal lanterns exists at the intersection. The eastbound right turn lane is controlled by 3 six aspect lanterns and 1 three aspect lantern. Whilst in fully controlled mode the 6 aspect lanterns at the intersection shows the a circular green and a red right turn arrow. Due to the right turn lane alignment it is suggested that while the fully controlled mode is on, the circular green drop out and that the 6 aspect lanterns facing the turn lane only display the red arrow. This treatment has not been included in this scope as it is currently been addressed by VicRoads' Traffic Operations.
The Following Treatments Have Been Identified To Address The Crash History At These Intersections:
Provision of signal mast arms to increase the visibility of the signals for westbound traffic at: - William Street / Flinders Street intersection; - Market Street / Flinders Street intersection.
Additional LED “No Right Turn” signs at - William Street / Flinders Street on the bridge viaduct pillar for southbound traffic. One exists on one of the viaduct pillars, but it should be duplicated on the next viaduct pillar to the west (between the northbound right and through traffic lanes); - William Street in the median just north of Flinders Street for southbound traffic; - Market Street / Flinders Street on Flinders Street for westbound traffic.
Additional advance warning signs of the right turn ban in William Street for southbound traffic before the Flinders Lane intersection;
The lantern on the centre median facing the south approach to be fitted with louvers.
An extra 3 aspect lantern fitted with louvers to be fitted in the centre median to face the right turn lanes.
Treatment Options Considered:
A preferred option to install LED traffic signals was considered to improve signal conspicuity at the intersection. However, advice received from Road Safety and Network Access indicated that this option would not be supported by the Federal Department of Infrastructure, Transport, Regional Development and Local Government, and consequently would not receive funding. Accordingly, an upgrade to LED traffic signals has not been included as part of the project scope.
Installation of a right turn red light camera to further deter the illegal southbound right turning movements in William Street was considered. The Department of Justice has conducted a preliminary site investigation and has advised that this camera installation is feasible, and they would support the installation (with additional warning signage). However, due to the additional signage proposed on the south bound approach, the installation of the red light camera was not considered necessary at this stage and does not form part of this proposal.
Consideration was also given to the provision of westbound queue detector loops in Flinders Street west of the William Street intersection to detect queued traffic and alter the signal phasing to reduce the amount of queuing for westbound traffic in the intersection. However, discussions with Metro North West's Manager Signal Operations indicates that reprogramming of the intersections along Flinders Street cannot take place without adversely impacting on the abutting area traffic flow. Accordingly, the
Scope Approval Report Flinders Street / William Street
installation of additional detector loops was not included in this proposal.
William Street is a north-south major traffic route connecting Peel Street and Flemington Road in North Melbourne with Flinders Street through the western side of the CBD.
Market Street is a north-south minor traffic route connecting Collins Street with Flinders Street.
Flinders Street connects Wellington Parade in the east with Docklands in the west via the south side of the CBD.
The proposed works do not compromise or adversely impact on current or proposed future network operations.
There are no anticipated impacts to current and future maintenance issues should the proposed road safety treatments be adopted.
No signal modification is proposed for the subject site and therefore, the proposal will not impact on the operation of bus and tram services within the area.
Principal Bicycle Network (Pbn)
The proposed treatments do not affect bicycle network users.
Road Safety Audit Requirements
In accordance with the VicRoads Road Safety Audit Policy, a risk assessment has been carried out for this particular project based on the proposed works and it was determined that a Road Safety Audit is required at functional or detailed design stage.
Project Objectives including Political and Community Issues:
There are expected to be no negative political or community issues involved with the proposed works.
Strategy: Arrive Alive 2008-2017
PROJECT EVALUATION Estimated Traffic Volume: Percentage of Commercial : Speed Zone:
Number of Fatal Accidents: Number of Injury Accidents:
Benefit/Cost Ratio (6.5% Discount Rate):
Net Present Value: $000's) 0 BCR Method: Road Safety
PROJECT FUNDING & ESTIMATE FOR APPROVED CONCEPT PART A - PROJECT MANAGEMENT $45,000PART B - DESIGN & INVESTIGATION $8,000 PART C - LAND ACQUISITION $0 PART D - CONSTRUCTION $50,000D(i) 1.0 Pre-construction Works $0 D(ii) 1.0 General Items $02.0 Structures and Concrete Works $0 3.0 Drainage $04.0 Formation Construction $0 5.0 Pavement Construction $0 6.0 Surfacing $0 7.0 Pavement Markings, Furniture & Misc $0 8.0 Signal Installation $0 9.0 Street Lighting $0 10.0 DDA $0 11.0 Provisional Quantities & Items $0PART E. - CONTINGENCY PROVISION $0 Program Administration (Oncosts) $0
Total Estimated Cost: $103,000 Funding source: Federal Blackspots Bid: $103,000 Estimate Status: Components funded by others Funding source (others) :
The cost estimate was checked by Craig Allan of Program Delivery on 29/09/2008.
TECHNICAL REFERENCE Status ReferenceSurvey Not Required Geotech Not Required Pavement Design Not Required Design Not Required Road Safety Audit A pre-opening road safety audit is required if the project has not had a detailed design audit. DDA Compliance NA
Land to be Acquired and Surplus Land for Disposal Previously Acquired Current Value: To Be Acquired Surplus for DisposalComment
Planning And Environment
Environmental Impact Checklist: Completed Date: PEPS: Completed Date: Is EPBC Act referral required :
Planning Type Reference No. Comments
Environmental Report Report No. Comments
COMMUNITY CONSULTATION Community consultation was held with the following: ; ; ; ; ; This project has been submitted by Melbounre City Council and any community consultation as part of this project will be undertaken by Council.
Utilities / Services Affected by Works Utility Status Comment
FUNCTIONAL REQUIREMENTS Existing NewNo of Carriageways Total Seal Width Unsealed Shoulder Width Length of road (km)
Bridges:Width b.k: Load limit:
TEMPORARY WORKS Traffic Management