Save Dimmeys. Council. TraffixGroup Response

8/4/2019 Save Dimmeys. Council. TraffixGroup Response

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Our Reference: GRP12958p#I4th October, 2011

Maddocks140 William StreetMELBOURNE3000

Attention: Ms Mimi Mareus, Senior AssociateDear MS Mareus,

140-160 SWANSTREET, RICHMOND: PROPOSED MIXED USE DEVELOPME NTFURTHERTRAFFIC ENGINEERING REVIEWOFVICROADS COMMENTSI have been instructed to comment on VicRoads'letter response (dated 30th August, 2011)to the VGAT order regardingthe traffic related impacts of proposed Dimmeys redevelopment on the intersection of Green Street and wari lee(VCAT Reference No. P623/2011, dated 5th August, 20th.Specifically, the Ttibunaliequired VicRoads to ad vise all parties of what mitigating works, if any, are sought in proximity tothe Swan Street and Green Streetintersection, having the benefit of the SIDRA modellanalysis as set out in t e expeevidence of Mr Walsh (Ref, CGI11247, Version DoI, dated 16th May. 20th.My response to this assessment considers the following documents:

. VicRoads' retorto VCAT (dated 30th August, 2011)

. Evidence Statement prepared by Mr Jason Walsh (Ref. CGI11247, Version Don, dated 16th May, 20th

. Evidence Statement prepared by Ms Charmaine Dunstan (dated 16th May, 2011). East Richmond Rai lway Precincl : Traff ic Engineerlng Assessment, prepared by Tram x Group (dated M ay, 2010,which was circulated during the course of the hearing. Traffic ImpaclAssessment prepared by OBrien Traffic (dated 26th November, 2010)

KeyissuesandrecommendationsbyVicRoadsFrom my reading of the VicRoads response, it is evidentthatthat VicRoads at paragraphs 4 and 7a) of its letter acceptsthe accuracy of the SIDRA m odelin terms of its assessment of delayslqueues affecting through tm IC an trams usingSwan Street as a consequence of an increased number of tightturning vehicles entering Green Street genera e y edevelopment.However, VicRoads disagrees with the adoption of the gap acceptance ctiterta used forthe light-turns into re^n reeand tight and left-turns out of Green Street which varyfrom the "default lrecommended SIDRA values. The application othese default values (i. e. generally requiring longer gaps to perlorm turns) lead to greater delays and queue lengthscompared to the Cardno results as specified in Table 2 and 3 of the VicRoads letter.VicRoads concludes that its revised SIDRA model also shows that the impacts of additional right-turning vehicles enteringGreen Stree t at Cleaiway times (i. e. afternoon peak h our) wil l not result in unacceptable delayslqueues to throu gh trafficand trains using Swan Street (paragraph 7a). This aspect of VicRoads wigina! concerns has been addressed, evenallowing forthe adoption of the 'default' SIDRA values.VicRoads further concludes that the delays and queues for vehicles exiting Green Street (p^iticylarly tight-turns) aleunacceptable on safety and operation grounds (paragrap h 7b) and recom mends the following mitigating works:

Traffic Engineers and Transport PlannersTraflixGroup Ply Ltd

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140-160 Swan Street, RichmondTraffic Engineering Review

I. Removal of on-street parking on both sides of Green Street for a distance of 40m from the intersection(paragraph 8b) to enable a sep arate right and left-turn exitlane to be formed in G reen Street.2. Installation of electronic parking signage at the intersection of Swan Street and Green Street indicating thenumber of parking spaces available in the supermarket carpalk,

My comments on this assessmentWith respectto VicRoads' recommendations, from a traffic engineehng perspective I have 00 issue with recommendationn0. 2 requirlng a dynamic parking sign as this is a sensible idea. It is expected that this would need to be attached to theDimmeys building and riot on the road reserve.With respect to recommendation no. I, I am satisfied that the banning of parking on the eastern side of G reen Street(entering lane) only is sufficient. In Section 12.5.3 of m y expert evidence, I concluded with respect to the increase indevelopment traffic using Green Streetthat:

Winstthis is a significantihcrease above existing volumes, subjectto the removal of parking on at least one sideof Green Street I am satisfied that given my site observatibns and the location of nearby tramc signals thatadequate gaps are available to accommodate the developm ent traffic at this intersection. There is also thepotential that some vehicles will use Railway Place to exitthe area, thereby further distributing the developmenttraffic.

Further, with respectto loading and waste collection, at Section 12.4. I of my expert evidence I conduded thatIt is noted that the internal laterral by Council's Waste Management Officer (dated 21st January, 2017) wassatisfied with the proposed waste coiledion arrangements, subject to the removal of on-street parking alongGreen Streetbeing approved,The issue of whether on^treet palmhg is retained along Green Street is a broad er issue to be resolved byCouncil for any roadwo, ks along this road. The level of trainc generated by this dev elopment, potential forgreater demands on anyparking placed in this location (due toproximify!, to the new supermarkety comb ined withthe loading requirements of this development, is likely to mean that it will be impractical to refa^^ on-streetparkingon both sides of Green Streetinto the future.

That is, I support the banning of parking on on e side of this road (m ost sensibly the eastern side) to enable two -way trafficmore freely and to accommodate the loading and waste collection requirements of this development.A similar condusion was drawn in Section 11.12 of the Traffic Impart Assessment report prepared by O'Btien Traffic(dated 26th Novembe r, 2010), which is the main document prepared by the applicantthat! had regard allhe time ofpreparing my evidence statement:

However given that parking is currently permitted on both sides of the 8.2 metre wide pavement, leaving spacefor only one di reof ion of haftc at a t ime to proceed, i r is recommended that parkihg be prohibi ted on one side ofGreen Streetto allow formo-waymovements to occur.With respect to the operation of the intersection, Ifound the impacts 10 be acceptable. My opinion was based on my ownsite observations at peak times and traffic surveys by Traffix Group, the traffic impact assessment by O anen Traffic(which excluded SIDRA) and my knowledge of the SIDRA analysis results in a project that was being undertakery byTramx G roup in relation to considering the potential impacts of ma king changes to traffic flow arrangements in the vicinityof Royal Place and Shakespeare Grove (i. e. near the Coles supermarkeVCouncilcarpark area). IWith respect to the work by Trafiix Group for Council, this assessment considered the combined impact of the Dimmeysdevelopment traffic (adopting the projected figures in the O'Brlen Traffic Report of 232 vehicle trips in the PM peak hour)and possible impact of closing Shakespeare Place to hanc. The implications of this closure would be that alltrafiicaccessing the Council carpark near Coles would need to enter via Green Street as Royal Place provides for exit onlymovements onto Swan Street.Accordingly, the traffic volumes considered in this SIDRA assessment related to some 358 vehicle turning movements(enteringIexiting) in the peak hour, which compares to 281 vehicle turning movements in the O'Brlen Traffic assessmentand 307 in the vehicle turning movements in the Cardno SIDRA analysis (which VicRoads has also adopted). Each

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I East Richmond Railway PredncL Tmfic Engineeting Assessmen t, prepared by Trafix Group (dated May, 2011 ), wilierI was cineu!ated during the course of theheating as I made reference to some o f its findings in my oral evidence. This donimentwas an internal docume nt prepared Yam C ity Coundl by other s o myonce ar^ incomplete alitie time oldrrulafit^ my evidence.Page 212958L#I, d DC


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140-160 Swan Street, RichmondTraffic Engineering Reviewassessment adopted a base traffic case using traffic surveys at different times2, however the results were generallysimilar.The Tramx Group surveys recorded 'actual gaps' in traffic, which enable a standard SIDRA assessment using trafficvolumes and an alternative assessment to be made using actual gaps (rather than theoretical gaps produced by SIDRA).The alternative assessment method (titled 'headway analysis'in the report) takes into consideration the true impact ofnearby traffic signals and any queuing (either as stationary vehicles or slow moving traffic) that potentially blocks Ih. e abilityof vehicles to exit Green Street. The analysis was completed for both the Friday and Saturday peak perlods orsupermarket use (i. e. peak Clearway and nori Clearway times).More importantly, the Tramx Group SIDRA analysis adopted the following gap acceptance ontorla as stated in the report. Left & rightturn movements from Green Street: Gap acceptance of5 seconds, Follow up headway of 3 seconds. Rightturn entry movem ents from Swan Street: Gap acceptance of4 seconds, Fol low up hea dway of 2 secondshis noted that there is only one approach lane marked in Green Street, which means that a lefttuming vehicle would needto queue behind a rlghttuming vehicle and this was reflected in the model.This gap acceptance Gri ter la is lower than the d efaul t SIDRA values used by VicRoads and closer to those ad opted byCardno.In my view, the adopted values are ap propriate, consistent with current practice and reflective of a low spee environm en .Swan Street has a 40kmlh speed zone between 7:00am and midnight (with 60kmft'I at other times) and the road eitheroperates as a. 3-1ane12-way road at peak times: two traffic lanes in the Cleanvay direction, one traff ic lane and kerbside parking inthe other, or. 2-1ane12-way road aloft-peak times: one traffic lane and kerbside parking in both directions.The default gap acceptance crlterla in SIDRA relied on by VicRoads are based on a 44ane/2-way road (i. e. two lang^ ineach direction) and are expected to be changes 10 reflect conditions. In fact, my own notes from the SIdra TrainingWorkshop that I slates that attended (relevant page attached at Appendix A to this letter):

The defaultvalues chosen for SIDRA INTERSECTION are based on two-lane approaches on a two-4) waymajorroad (i. e. 4.1ane two-way). Values for use in SIDRA INTERSECTION recommended forother road geometry conditions are given above. In allcases, the user may wlsh to overri a eSIDRA INTERSECTION default and recommended values based on good engineering judgementtaking Into account specific intersection geometry and flow conditions.

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These notes support the adoption of the following ranges:Righttum entry across I lane (as parking occurs on south side during PM peak): Gap acceptance of 3.5-4.5seconds, Follow up headway of 3-2 seconds - the Tramxand Cardno figures fallin this range.Righttum exit across 3 lanes (as parking occurs on south side during PM peak): This would fall between the 2-lane, 2-way and 4-1ane, 2-way assessment due to the Clearway and parking arrangements as note a ve.Given the speed environment and traffic flow conditions, I am comfortable in adopting the lesser o I eserequirements (i. e. using good engineering judgement), The 2-1ane, 2-way crlterta specify a gap acceptance of 5-6 seconds, and a follow up headway of 3-4 seconds. The Tramx assessment is within the range and the Car 00assessment is marginalIy below this range (critical gap of 4.5, follow-up headway of 2.5 seconds).

. Lofturn exit: Gap acceptance of 4-6 seconds, Follow up headway of 2.5-3.5 seconds - the Tramx an ar 00figures fallin this range.Similar SIdra tables and guideline information (although spread across several pages) are included ij the Sidra. UserGuide (Part 3). Similarly, the program help function states that 'gapacceptance parameters approprlqte to p^Iticuarintersection geometry and flow conditions should be selected using good engineering judgement and speciie as inpu ortwo-way sign^on trolled intersections. Local driver characteristics should also be taken into accountin this process.

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aTraf ix Group surveysweie undined on Fr iday 6th May and Sanrday 7th M ay. 2011Cardno surveys were conductsd on Friday 29. Apriland Sahirday 30nApti1. 2011.0'8rlen Tramcsuiveyswa'econdudedoriThursday 11. June. 2009.12958L#,. doc Page 3


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140-160 Swan Street, RichmondTraffic Engineering ReviewIn in view it is ntirel a 10 hateto make these ad'ustinents o rated a toaltocaltrafiic conditions.This observation is made in Section 2.1 of the Tramx Group assessment of the possible Shakespeare Place closure:

Pedestrian operated signals are located in Swan Street between the Swan StoatGreen Street and Swa nStreetRoyal Place intersections. A tram service operates along Swan Street with tram stops located on bothsides of the road at the pedestn^n operated signals. A 40kmffi shopping centre speed limit applies in SwanStreet between 7:00am andmidnight with the speed limitreverting to 60kmffiatothertimes,There are a number of closely spaced unsignalised side road intersections located along Swan Street within thestrip shopping centre. The combihed effects of the stripshopping centre environment with the pedestrian signals,kerbside parking, train stops andtuming tremoresultin regularqueues of slowmoving traffic foming along SwanStreet.

Section 11 of the O'Brien Traffic Report similarly notes:The pedestrian signa^ located approximately 60 metres east of the subject site, together with the intersectionsignals located approximately 90 metres west of the subject site, provide frequent gaps in the Swan Streettraificthat allow vehicles to turn rightihto By10n Street, Green Street and Shakespeare Place and n'ght out of By10n

Street, Green Street andRoyalPlace withoutsignificant delay. Left turns do notrequire gaps in both directions oftrainc, and are also observed tooccurwithoutdelay.The same observation was made by MrWalsh (end of Section 5.4 of his statement):

From observation, it I^ noted during peak times queues can fom in Swan Street, and motorists egressing sidestreets enter the traffic stream byjoining orenteiingthe slowmoving queue.I have also made a similar observation as quoted previously under this heading (Section 12.53).As noted in the report, the Tramx mod elwas further adjusted as follows:

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To make the m odel more realistic the capacities for the turning movements out of Green Street have beenreduced to allow forthe presence of stationary queues in Swan Street. For the Friday peak, it w as found thatstat ionary queues occurred for 32 minutes out of the I hourperiod, so the capachy has been reduced by 54^.Forthe Saturdaypeak, it was found that stationary queues occurred for 17 minutes out offhe I hourpenbd, sothe capacity hasbeen reduced by 28%,

The Tramx Group report conduded with respectto this assessment thatThe SDRA results indibate that the intersection will operate acceptably during both the Fridayand Saturdaypeakperiods following the projected increases in tramc volume resuhing from both the Dimmeys site redevelopmentand the closure of Shakespeare Place. In particular the degree of saturation remains below 0.8 for allmovements which indicates good conditions, winstthe average delay is also less than 30 seconds fortums outof Green Street andno more than loseconds fortratfic approaching in Swan Street. Note that the conditions areworse in Swan Street on the Saturdayas there is 00 Clearway which applies at that time.

The recorded 95th percentile queue in Green Street(assuming I shared exitlane) was 18m. The average delay was 26seconds. This compares to the Cardno assessment of 7m queue and delay of 22 seconds (noting that the Tr^ffix Grouptraffic volumes were higher and the model was adjusted to a greater extent to reflectthe impact of queued vehicles). Thecoinparable VicRoads assessment was a 29m queue and delay of 112 seconds.Section 7 of the Tramx Group report indudes the headway analysis using the actual gaps. This assessment found that theSIDRA analysis, even allowing forthe adjustments, was conservative, The report concluded that:

The resufts from the headway analysis (with lower degrees of saturation predicted) show that the intersectibn isl ikely to perform better than what has been calculated by the SIDRA Intersect ion program. The reason forthedifference is that SDRA Intersection assumes a random distrtbution offraffle amvats on Swan Street whereas inreal ly bunching occurs due to trams and nearby I faf i ic . The impacts of b unching are ref lected in the headwayanalysis by measuring the actual gaps between vehicles.Based on the above, I am satisfied that the extent of 'no stopping required by VicRoads is likely to be excessive as theassessment is highly conservative given the gap acceptance ontorla adopted and that any SIDRA analysis o t isintersection is inherently conservative due to the 'bunched' traffic conditions from nearby signals.Therefore, I am satisfied that banning parking on one side (eastern side) of Green Street will adequately address theconcern ofVicRoads.

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140-160 Swan Street, RichmondTramc Engineering ReviewItrustthis information meets with your requirements. Please contact me ifyou require any further information.Yours faithfully,TRAFFIXGROUPPTYLTD

CHARMAINE DUNSTANDirectorWWW. tramxgroup. coin. au

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140-160 Swan Street, RichmondTraffic Engineering Review liraffixGro, ,p

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Appendix A



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Gap acceptance parameters recommended by theAUSTROADS (2002) Urban Road Design Guide andthe SIDRA I TERSECTION User GuideType of movement

Left turn (1)Through movement crossingone'wa road

. 2-1aneone-way

. 3-1aneone-way. 4-1aneone-wayThrough movement crossingtwo-wa road

. 2-1anetwo-way

. 4-1anetwo-way

. 6-1anetwo-wayRightturn from majorroad (2)

. Acrosstlane

. Across2 lanes

. Across31anesRi htturn from minor road 3

. One. way

. 2-1anetwo. way

. 4-1anetwo-way

. 6-1anetvvoayayMerge from acceleration lane

This table applies to intersections controlled by two-way stop or give-way (yleld) signs as we as moregeneral gap-acceptance operations. Notes lay to (4) below are notincluded in the AUSTROAD u e.This is considered to apply to left-turn movements from minor road, as well as s ip- aria e - urnnmovements from minorroad and majorroad.This case Is relevantto two-waymajorroad conditions with one direction of the majorroadopposing (,-lane, 2-1ane or 3-1ane).The conditions specified (one-way, 2-1ane two-way, 4-1ane two-way, 6-1ane two-way) are relevanttothe opposing movement lanes on the majorroad.The defaultvalues chosen for SIDRA INTERSECTION are based on two-lane approaches on a two-way majorroad (i. e. 4-1ane two-way). Values for use in SIDRA INTERSECTION recoinmen^ed forother road geometry conditions are given above. In allcases, the usermaywlsh to override I eSIDRAINTERSECnON defaultand recommended values based on goodongineeringjudgementtaking into account specific Intersectlon geometry and flow conditions.

3GO:.>or. \to\^'('--.^- , co-f>O c, .,,,,

AUSTROADS(2002)Critical

gap(seconds)5

\

Follow-upheadway(seconds)

2 - 3

Defaultvalues orrecommendedranges for use In SIDRAINTERSECnON (4)Follow-upritical gap headwayseconds) (seconds)

5.0 (4-6) 3.0 (2.5-3.5)

588

4 - 55 - 75 . 8

355

456

(2)

4.5 - 5.56.5 5.8

7 - 8

2 . 32.5 - 3.5

3 . 5

(3)

234

(4)

35883

2.5 . 3.53.5 3-5

4 - 5

.5 . 4.55 4-55 - 6

33552

16

3 - 55 - 6

.0 6-87 - 83 -4

2 .32.5 2.3

3 - 4

2.5 . 3.53 . 4

4.0 3-54 . 52 . 3

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Save Dimmeys. Council. TraffixGroup Response