Total Lawson Development ACTPLA 16 January 2009 Document No.:
Prepared for ACTPLA Prepared by Maunsell Australia Pty Ltd Level 2, 60 Marcus Clarke Street, Canberra ACT 2600, Australia T +61 2 6201 3000 F +61 2 6201 3099 www.maunsell.com ABN 20 093 846 925 In association with Purdon Associates 16 January 2009 60047642 Maunsell Australia Pty Ltd 2009 The information contained in this document produced by Maunsell Australia Pty Ltd is solely for the use of the Client identified on the cover sheet for the purpose for which it has been prepared and Maunsell Australia Pty Ltd undertakes no duty to or accepts any responsibility to any third party who may rely upon this document. All rights reserved. No section or element of this document may be removed from this document, reproduced, electronically stored or transmitted in any form without the written permission of Maunsell Australia Pty Ltd. Revision B 16 January 2009
Quality Information Document Ref 60047642 Date 16 January 2009 Prepared by Tom Brimson Reviewed by Peter Evans and Tim Rampton Revision History Revision Revision Date Details Name/Position A 03/11/2008 For information Rod Williams Authorised Signature B 16/01/2009 For information Rod Williams Revision B 16 January 2009
Table of Contents Executive Summary i 1.0 Existing Traffic Conditions 1 1.1 Road Network 1 1.2 Traffic Volumes 2 1.3 Traffic Safety 3 1.4 Current Intersection Performance 4 1.4.1 William Slim Drive / Ginninderra Drive 5 1.4.2 Aikman Drive / Ginninderra Drive 6 1.4.3 Hayden Drive / Ginninderra Drive / Baldwin Drive 8 1.4.4 Baldwin Drive / Maribyrnong Avenue South 10 1.4.5 Baldwin Drive / Maribyrnong Avenue North 12 1.4.6 Baldwin Drive / William Slim Drive 14 1.5 Public Transport 15 1.6 Access Opportunities 16 2.0 Proposed development 17 2.1 Project Traffic Generation 18 2.2 Future Intersection Performance 21 2.3 Initial Assessment of Results 26 2.4 Traffic Analysis 26 2.5 Road Cross Sections 27 2.5.1 External Roads 27 2.5.2 Internal Roads 27 2.6 Public Transport 27 2.7 Pedestrian and Cyclists Network 28 3.0 Conclusions 29 Revision B 16 January 2009
Executive Summary Background The development of Lawson is likely to generate a range of dwelling yields dependent upon the particular layout and plan that is finally developed. The LDA have indicated that up to 1500 dwellings is desired, where as this current study has identified that a yield closer to 900 dwellings is more easily achieved for that area within the ACT government land. In addition the previous planning for Lawson identified the potential for about 600 dwellings on the adjacent Defence site. In order to identify the likely impacts a two values of yield were assessed: 1500 ACT dwellings reflecting a high number of medium density units plus 600 Defence dwellings as the maximum likely yield to be achieved of 2100 dwellings, and 600 ACT dwellings reflecting all standard residential development plus 600 Defence dwellings as the minimum yield likely of 1200 dwellings. The traffic generated from these yields was distributed to the adjacent road network. Traffic generation has been assumed at 8 trips per day for standard residential and 6 trips per day for medium density together with a peak hour factor of 10% of daily traffic in the AM peak hour. For the higher yield of 2100 lots, it was assumed that 50% will be medium density resulting in an average yield of 7 trips per dwelling where as for the low yield all lots were assumed as standard residential for this purpose of assessing traffic implications 8 trips per day. Traffic Impacts The following conclusions have been drawn from the traffic assessment: Six lanes are required on Ginninderra Drive between William Slim Drive and Baldwin Drive / Haydon Drive for 2021 based on the strategic traffic model forecasts and the expected traffic demands from the University of Canberra proposed masterplan. These lanes are needed irrespective of the development yield between the ranges of 1200 and 2100 dwellings for the total Lawson Development However the demand for 6 lanes appears to be very highly influenced by the proposed developments at the University of Canberra. The options for the development with the University of Canberra will require detailed assessment, particularly with regard to the scale of the development and the connections to the external road network. The intersection of Maribyrnong Avenue (south) Baldwin Drive will require widening by one lane on Baldwin Drive. Note traffic signals have been selected to provide for the safe movement of pedestrians (school children and bus passengers) across Baldwin Drive. External Road Network The existing bridge across Lake Ginninderra provides a travelled path of approximately 11.0 metres. This provides sufficient space for three 3.4m lanes plus a 0.4m shoulder / clearance to the bridge barrier. However this lane arrangement will require cyclists to use the adjacent shared path - in exactly the same way as occurs on Commonwealth and Kings Avenues. Revision B 16 January 2009 Page i
Internal Road Network The two key internal roads will need to provide for possible bus routes from the extension of Aikman Drive to Maribyrnong Avenue (South) and the proposed extension of Allawoona Street from the University of Canberra. The forecast internal traffic flows indicate that for a development of 1500 dwellings a total of about 10,500 trips will be generated. These will be reasonably uniformly spread over the three links connecting to the external network indicating that it is likely that traffic levels will possibly be in the order of 4,000 vpd on the main link between Aikman Drive extension and Maribyrnong Avenue. All three proposals provide for medium density development on the approaches to the major roads and hence the expectation is that these traffic levels will be well within those An indication of possible traffic flows at the development connections to the external network are shown below in Figure 2-6. Pedestrian and Cyclists The primary cycle network will be a system along the foreshore of Lake Ginninderra. In addition the trunk network along Ginninderra Drive for both on and off road cycling is expected to be maintained. Secondary connections will be possible along Reedy Creek and also the boundary between the Defence land and ACT government land. Footpaths will provide connections to Maribyrnong Avenue, Allawoona Street and Aikman Drive. Public Transport The three concept plans provide for the opportunity to contain all of the site within a 400m radius of either one or two internal bus routes or an existing external bus route. The extension of the access into the University of Canberra provides a good opportunity to connect these two developments with public transport whilst the extension of the bus route from Maribyrnong Avenue (south) to Aikman Drive provides an opportunity for a direct connection to the Belconnen Town Centre. In addition it is understood that the public transport planning currently being undertaken for the ACT government proposes a high frequency bus service along Ginninderra Drive that will be able to service Lawson. Conclusion The proposed development of Lawson is quite close to the Belconnen Town Centre and the University of Canberra thus potentially generating a higher proportion of walk and cycle trips than would be the case for developments further removed from this central location. There are various possible scheme for the development but all have common access opportunities of extending Aikman Drive, Alawoona Street or Maribyrnong Avenue (south). These connections provide for appropriate permeability into the development, the opportunities for two internal bus routes and being sufficiently circuitous to not attract through traffic. The future traffic flows indicate that there will be a need to widen Ginninderra Drive to 3 lanes in each direction: primarily to meet the demands from a growing Gungahlin and west Belconnen. The timing of this widening needs to be considered from an assessment of the competing road space needs as identified from strategic modelling and scenario testing. Revision B 16 January 2009 Page ii
1.0 Existing Traffic Conditions 1.1 Road Network The site is surrounded by arterial and sub-arterial roads as follows: Baldwin Drive is an undivided sub-arterial road with generally two lanes is each direction. The speed limit varies between 60 and 80 km/h, however a 40 km / h school zone operates past the high school from 0800 1600. Ginninderra Drive is a divided 4 lane arterial road with a speed limit of 80 km/h. William Slim Drive is one carriageway of a future 4 lane divided road that is currently operating as a two lane two way road with an 80 km/h speed limit. The current road network has been shown in Figure 1-1. Figure 1-1: Current Road Network Revision B 16 January 2009 Page 1
1.2 Traffic Volumes The existing traffic flows are shown in Table 1-1 and Table 1-2 below. Table 1-1: Ginninderra Drive AM Peak Hour Volumes Road AM Peak Hour Volumes Eastbound 1981 Westbound 661 Baldwin Drive (North Eastbound 494 end) Westbound 177 Baldwin Drive / Hayden Northbound 475 Drive Southbound 1319 Aikman Drive Northbound 498 Southbound 1167 Maribyrnong Drive Eastbound 800 South Westbound 1968 Maribyrnong Drive Eastbound 277 North Westbound 369 William Slim Drive Northbound 199 Southbound 1245 Combined AM Peak Hour Volumes 2642 671 1794 1665 2768 646 1444 Table 1-2: Ginninderra Drive PM Peak Hour Volumes Road PM Peak Hour Volumes Eastbound 935 Westbound 1656 Baldwin Drive (North Eastbound 319 end) Westbound 445 Baldwin Drive / Hayden Northbound 1073 Drive Southbound 475 Aikman Drive Northbound 768 Southbound 317 Maribyrnong Drive Eastbound 546 South Westbound 446 Maribyrnong Drive Eastbound 563 North Westbound 306 William Slim Drive Northbound 748 Southbound 1245 Combined PM Peak Hour Volumes 2591 764 1548 1085 992 869 829 These flows are shown in Figure 1-2 Revision B 16 January 2009 Page 2
PM AM 366 194 813 411 William Webb Dr 83 William Webb Dr 94 188 83 123 683 208 246 809 125 355 90 249 228 107 57 1518 144 108 69 719 369 684 456 140 1105 797 260 55 1834 94 540 606 789 27 465 661 285 960 Baldwin Dr 310 736 253 826 240 378 351 147 60 139 90 51 498 Ginninderra dr 150 Alkman Dr Haydon Dr 67 14 733 194 220 379 499 1277 234 407 326 322 1656 215 124 572 Baldwin Dr 1324 148 143 234 98 83 332 436 168 246 612 866 Ginninderra dr Alkman Dr Haydon Dr 52 AM PM Figure 1-2 2008 traffic Volumes 1.3 Traffic Safety Data available from Roads ACT indicated that there have been 653 crashes recorded in the immediate vicinity of the site in the five year period from 1 January, 2003 to 31 December, 2007 or an average of 130 per year. There were no fatal crashes recorded during the period. These cashes are shown in Table 1-3. Table 1-3: Crash Statistics Intersection Number of Accidents Property Damage Only Severity Recd Med Treat Adm to Hosp Baldwin Dr / Chucculba Cr / Baldwin Dr 38 37 1 0 0 Baldwin Dr / William Slim Dr / William Slim Dr Aikman Dr / Ginninderra Dr / Ginninderra Dr Baldwin Dr / Maribyrnong Ave / Baldwin Dr / Maribyrnong Ave (SW) Baldwin Dr / Ginninderra Dr / Hayden Dr / Ginninderra Dr Ginninderra Dr / William Slim Dr / Ginninderra Dr Fatality 98 97 1 0 0 125 123 1 1 0 20 17 3 0 0 215 211 2 2 0 81 79 1 1 0 Baldwin Dr / Gum St / Baldwin Dr 1 0 1 0 0 Baldwin Dr / Maribyrnong Ave / Baldwin Dr Dumas St / William Slim Dr / William Slim Drive 51 47 4 0 0 24 19 5 0 0 Total 653 630 19 4 0 These crash sites are shown Figure 1-3 Revision B 16 January 2009 Page 3
Figure 1-3 Crash Sites at Lawson This analysis shows that there are about 3 crashes per month at the Ginninderra Drive / Baldwin Drive / Haydon Drive intersection and more than 1 per month at Aikman Drive / Ginninderra Drive. Most crashes are property damage only with only 3.5% being recorded as involving an injury. Note that it is not possible to identify which intersection of Maribyrnong Avenue.Baldwin Drive that each crash record refers to. 1.4 Current Intersection Performance There are seven main intersections around the site and likely to be most affected by the proposed development. These intersections are: William Slim Drive / Ginninderra Drive Aikman Drive / Ginninderra Drive Hayden Drive / Ginninderra Drive / Baldwin Drive Baldwin Drive / Maribyrnong Avenue South Baldwin Drive / Maribyrnong Avenue North Baldwin Drive / Chuculba Crescent Baldwin Drive / William Slim Drive The performance of these intersections has been undertaken using SIDRA 3.2 for traffic turning movements derived from either detector counts or manual counts for the left slip lanes. Assumptions used in the analysis include: Revision B 16 January 2009 Page 4
Peak hour factor of 90% Median values of gap acceptance values in the SIDRA users guide for each turning movement Traffic signal phasing as provided from TAMS Default values for roundabout analysis The performance indicators for these intersections are presented in graphical form for each of the intersections in the following sections. Full details of the analysis are presented in Appendix A. 1.4.1 William Slim Drive / Ginninderra Drive The existing performance indicators of this intersection are presented in Figure 1-4. C = 60 seconds Cycle Time Option: Program calculated cycle time Phase times determined by the program. Phase G Phase H Phase I Green Time = 22 seconds Phase Time = 28 seconds Phase Split = 47 % Green Time = 13 seconds Phase Time = 19 seconds Phase Split = 32 % Green Time = 7 seconds Phase Time = 13 seconds Phase Split = 22 % AM Performance DoS PM Performance DoS: Av Delay Av Delay: Revision B 16 January 2009 Page 5
Queue length Queue length: Spare capacity Spare capacity Figure 1-4 Existing performance William Slim Drive / Ginninderra Drive intersection 1.4.2 Aikman Drive / Ginninderra Drive The existing performance indicators of this intersection are presented in Figure 1-5. C = 150 seconds Cycle Time Option: Program calculated cycle time Ginninderra Drive 85 85 60 Ginninderra Drive Phase times determined by the program. Phase G Phase H Phase I Green Time = 19 seconds Phase Time = 25 seconds Phase Split = 17 % Green Time = 80 seconds Phase Time = 86 seconds Phase Split = 57 % Green Time = 33 seconds Phase Time = 39 seconds Phase Split = 26 % Revision B 16 January 2009 Page 6
AM Performance DoS: PM Performance DoS: Av Delay: Av Delay: Queue length: Queue length: Spare capacity: Spare capacity: Figure 1-5 Existing performance Aikman Drive / Ginninderra Drive intersection Revision B 16 January 2009 Page 7
1.4.3 Hayden Drive / Ginninderra Drive / Baldwin Drive The existing performance indicators of this intersection are presented in Figure 1-6. AM Performance DoS: PM Performance DoS: Av Delay: Av Delay: Revision B 16 January 2009 Page 8
Queue length: Queue length: Spare capacity: Spare capacity: Figure 1-6 Existing performance Baldwin Drive / Haydon Drive intersection Revision B 16 January 2009 Page 9
1.4.4 Baldwin Drive / Maribyrnong Avenue South The existing performance indicators of this intersection are presented in Figure 1-7. Marribyrnong Avenue AM Performance DoS: PM Performance DoS: Av Delay: Av Delay: Revision B 16 January 2009 Page 10
Queue length: Queue length: Spare capacity: Spare capacity: Figure 1-7 Existing performance Baldwin Drive / Maribyrnong Avenue Drive intersection Revision B 16 January 2009 Page 11
1.4.5 Baldwin Drive / Maribyrnong Avenue North The existing performance indicators of this intersection are presented in Figure 1-8. Baldwin Drive AM Performance DoS: Baldwin Drive PM Performance DoS: Av Delay: Av Delay: Revision B 16 January 2009 Page 12
Queue length: Queue length: Spare capacity: Spare capacity: Figure 1-8 Existing performance Baldwin Drive / Maribyrnong Avenue Drive (north) intersection Revision B 16 January 2009 Page 13
1.4.6 Baldwin Drive / William Slim Drive The existing performance indicators of this intersection are presented in Figure 1-9. AM Performance DoS: PM Performance DoS: Av Delay: Av Delay: Revision B 16 January 2009 Page 14
Queue length: Queue length: Spare capacity: Spare capacity: Figure 1-9 Existing performance William Slim Drive / Baldwin Drive intersection This assessment shows that the road network is currently operating quite efficiently however the intersection of Ginninderra Drive / Baldwin Drive / Haydon Drive is approaching capacity. 1.5 Public Transport The existing public transport services for the area surrounding Lawson are shown in Figure 1-10 Revision B 16 January 2009 Page 15
Figure 1-10 ACTION weekday bus services This shows that there are currently four services on Baldwin Drive that could service a large portion of Lawson with the existing route and a further two on William Slim / Ginninderra Drive that could also serve part of the site. 1.6 Access Opportunities The opportunities for access to Lawson include: Conversion of the Tee junction of Baldwin Drive / Maribyrnong Avenue to a cross intersection Conversion of the Tee junction of Aikman Drive / Ginninderra Drive to a 4 way intersection Future access to the Defence land opposite Chuculba Crescent Revision B 16 January 2009 Page 16
2.0 Proposed development Three options for the development of Lawson have been considered. Although these development types are considerably varied they all have comment access arrangements and hence the broad assessment of external needs can be undertaken with confidence that any of the options has the transport implications considered. The three options are shown in Figure 2-1, Figure 2-2 and Figure 2-3. Figure 2-1 Indicative layout N0 1 Figure 2-2 Indicative layout No 2 Revision B 16 January 2009 Page 17
Figure 2-3 Indicative layout No 3 2.1 Project Traffic Generation The project is likely to generate a range of dwelling yields dependent upon the particular layout and plan that is finally developed. The LDA have indicated that up to 1500 dwellings is desired, where as this current study has identified that a yield closer to 900 dwellings is more easily achieved for that area within the ACT government land. In addition the previous planning for Lawson identified the potential for about 600 dwellings on the adjacent Defence site. In order to identify the likely impacts a two values of yield have been assessed: 1500 ACT dwellings reflecting a high number of medium density units plus 600 Defence dwellings as the maximum likely yield to be achieved of 2100 dwellings, and 600 ACT dwellings reflecting all standard residential development plus 600 Defence dwellings as the minimum yield likely of 1200 dwellings. The traffic generated from these yields have been distributed to the adjacent road network. Traffic generation has been assumed at 8 trips per day for standard residential and 6 trips per day for medium density together with a peak hour factor of 10% of daily traffic in the AM peak hour. For the higher yield of 2100 lots total it has been assumed that 50% will be medium density resulting in an average yield of 7 trips per dwelling where as for the low yield all lots have been assumed as standard residential for this purpose of assessing traffic implications 8 trips per day. The indicative distribution for 2100 Lawson dwellings including the Defence land is shown in Figure 2-4 Revision B 16 January 2009 Page 18
173 103 305 201 Figure 2-4 General Distribution of Lawson Trips for 2100 dwellings (including Defence site) Future traffic forecasts for the adjacent arterial road network were obtained from TAMS Transport Policy unit and the forecast flows for 2021 are shown in Figure 2-5 Figure 2-5 TAMS 2021 forecast traffic flows This diagram shows that the flows along Ginninderra Drive are expected to climb rapidly from the existing flows by about 30% by 2021. The metropolitan and local land use assumptions that generated these forecasts are shown in Table 2-1 and Table 2-2 respectively. Revision B 16 January 2009 Page 19
Table 2-1 Regional Land Use Data in Model 2021 LAND USE DATA SUMMARY Population Employment Retail Space School Enrolments Tertiary Enrolments 1 - Gungahlin 64010 12285 170705 7215 0 2 - Belconnen 91390 30235 283915 11885 14530 3 - North Canberra 50840 71460 236440 9525 26940 4 - South Canberra 28400 49915 498695 8535 1340 5 - Woden 55800 31615 184010 8840 3720 6 - Jerrabomberra 920 7070 61590 0 0 7 - Tuggeranong 85290 23530 197320 14970 1300 8 - Queanbeyan 36950 13010 75000 7025 500 9 - Externals 0 0 2575 0 0 10 - Molonglo 23270 2095 30500 425 600 11 - Majura 120 9110 37000 0 0 TOTAL 436990 250325 1777750 68420 48930 Table 2-2 TAMS Detailed Model data District No Zone Description Emme/2 TAZ AE 2018 Based 2021 Population 2021 Employment 2021 Retail Space GFA (m2) 2021 School Enrolments 2021 Tertiary Enrolments Assessment Emme 2 Model 2 Lawson 380 2800* 95 0 0 0 * The 2800 residents are equivalent to a total development in Lawson including the Defence land of about 1000 1200 dwellings Of note is that for the purpose of this strategic model the following conditions are included: the district of Lawson is connected only to Baldwin Drive. Ginninderra Drive is six lanes between Coulter Drive and William Slim Drive Gungahlin Drive extension appears to be only a single lane in each direction For the future situation the EMME 2 modelled 2800 residents generated 758 trips outbound and 260 trips inbound. The volume of inbound traffic appears high for a residential area and a value of about 100vph would be typical for this type of development. For these two scenarios the traffic assessments the associated traffic generation is shown in Table 2-3 Table 2-3 Comparison of TAMS Land Use Data and Potential Land Use Scenarios Assessment Scenario 2 Zone Description AE 2018 Based 2021 Population Dwellings 2021 Employment Outbound trips Inbound Emme 2 Lawson 2800 1100 95 758 260 Model ACT and Scenario 1 Defence 3600 2100 0 1323 147 trips 1800 1200 0 756 84 The EEM 2 model traffic generation for Lawson was all directed onto Baldwin Drive. These EMME 2 modelled flows were subtracted from the network flows. The Lawson forecast generated and attracted flows were derived and distributed along the expected travel patterns assumed for the year 2021. These internal traffic flows generated from the Lawson Development flows were then added to the strategic modelled flows for the external network generally envisaged for the suburb. Revision B 16 January 2009 Page 20
It is of note that the traffic forecasts for Ginninderra Drive between William Slim Drive and Aikman Drive are about 30% higher than are currently carried on the 6 lanes of Northbourne Avenue. The traffic lane capacity at signalised intersections is in the order of 900 1000 vph. The traffic demand of 3475 vph indicates that at least 3 lanes will be required for Ginninderra Drive traffic between William Slim Drive and Aikman Drive and that there may be a need for these strategic forecasts to be revised. In addition it is noticed that the GDE is only carrying ~ 2000 vph which may indicate that it may be coded as a single lane in the Emme 2 model or that there is severe congestion to the south that prevents access from Ginninderra Drive. There is also a reasonably high inbound traffic demand shown in the model results 260 inbound compared to 758 outbound in the AM peak or ~25%. This is a very high proportion of trips with current reverse direction peak trips often about 10% of total indicating a need to review the assumptions in the strategic model with such a high proportion of entering trips. Future intersection turning movements were derived by a simple pro-rata distribution of the 2021 modelled link flows in the same proportion as the existing intersection turning movements less those in the model for Lawson. The results of the analysis for both scenarios and the AM and PM peak periods are summarised in the following section. Of note is that the University of Canberra is a substantial traffic generator and that the University is currently reviewing it s masterplan which may result in changed development scale and type as well as a change to the internal connections to the external network. 2.2 Future Intersection Performance Each of the intersections on the surrounding arterial the access to the University of Canberra / Ginninderra Drive was assessed. Whilst the general intentions of the University are known the details of exactly how many residential units and other features of scale are unknown. Hence the specific needs for the intersection of Ginninderra Drive / University access need to be taken into account by the University proposals rather than Lawson. Initial analysis of the strategic traffic forecasts indicate that Ginninderra Drive will need to be increased in capacity to 6 lanes - 3 in each direction. This does not mean that this widening needs to be undertaken as part of the Lawson Development, but rather the combination of the need to update the EMME 2 model and the possible University of Canberra proposals need to be assessed in a strategic sense before detailing capacity improvements. A summary of the intersection performance results for 1500 and 600 ACT dwellings are shown in Table 2-4 and Table 2-5 respectively. Note both options assume 600 Defence dwellings. Revision B 16 January 2009 Page 21
Table 2-4 Intersection Performance Assessment 2100 dwellings Geometry AM Flows PM Flows Lawson Access Lawson Access 100 85 85 60 Ginninderra Drive 80 Ginninderra Drive Aikman Drive 100 80 70 Aikman Drive Ginninderra Drive / Aikman Drive Average delay Average Delay 120.6secs, LoS F Lawson East Average 54.2, LoS D UCan Ginninderra Drive UCan Revision B 16 January 2009 Page 22
Geometry AM Flows PM Flows Baldwin Drive Average Delay 76.4, LoS F Baldwin Drive Average 91.5, F Baldwin Drive 80 170 90 100 100 Ginninderra Drive 70 50 170 Ginninderra Drive 50 75 Haydon Drive Haydon Drive Haydon Drive Average 57 secs, LoS E Baldwin Drive Average 39.1, LoS C Lawson Marribyrnong Avenue Baldwin Drive Average 56.7 LoS E Average 32.4, LoS C Revision B 16 January 2009 Page 23
Table 2-5 Forecast Intersection performance with reduced development (1200 dwellings total) Geometry AM Flows PM Flows Lawson Access Lawson Access 100 Ginninderra Drive Ginninderra Drive Aikman Drive 100 80 70 Aikman Drive Ginninderra Drive/ Aikman Drive Average delay Average Delay 47.8 LoS D Lawson East Average 43.7 LoS D Lawson East UCan UCan Ginninderra Drive UCan Average 70.5 LoS E Average 33.7 C Revision B 16 January 2009 Page 24
Geometry AM Flows PM Flows Baldwin Drive Baldwin Drive Baldwin Drive 80 170 50 75 Haydon Drive Haydon Drive Haydon Drive Average 57.6 secs LoS E Average 47.7 LoS DC Baldwin Drive Lawson Marribyrnong Avenue Baldwin Drive Average 42.7 LoS D Average 38.2 LoS C The details of the assessment are enclosed at Appendix A Revision B 16 January 2009 Page 25
2.3 Initial Assessment of Results These results show that Ginninderra Drive will not be able to handle the demands forecast for the corridor irrespective of the level of the Lawson development within the ranges assessed. These results do not mean that the scale of development needs to be reduced but rather that the traffic modelling reflect the capacity constraints of the adjacent network However the results for the most intensified development show that there will be significant delays which one could expect to result in the following ameliorating factors: Traffic will redistribute across the whole region to links with less congestion to achieve the shortest overall travel time Traffic will spread across a wider peak period. There will be a higher proportion of public transport trips There will be a higher proportion of walk and cycle trips to and from the Belconnen Town Centre Traffic to and from the university of Canberra will be spread over a longer period of time with less of a peak flow. 2.4 Traffic Analysis The above results indicate the following planning reviews are warranted: The scale, type and access capacity for the proposed intensification of development at the University of Canberra, The network capacity within the EMM2 model The network connections to Lawson that are now envisaged being incorporated in the strategic model Land use / trip generation update to the strategic model to reflect the current proposals for Lawson Mode split reviews for the proposed Lawson development and trip relationships with the University of Canberra. However Ginninderra Drive has a higher peak hour factor (PHF peak hour flow / daily flow) at 12% where as the typical arterial PHF in Canberra is 9% 10%. This indicates that Ginninderra Drive and its intersections carry proportionally less traffic in the off peak periods compared to other arterial despite serving the University of Canberra. This means that off peak traffic on Ginninderra Drive has a higher Level of Service than other ACT arterial roads and that there is an opportunity for significant peak spreading to carry the demands. Notwithstanding these recommendations, the following conclusions have been drawn from the assessment: Six lanes are required on Ginninderra Drive between William Slim Drive and Baldwin Drive / Haydon Drive for 2021 based on the strategic traffic model forecasts and the expected traffic demands from the University of Canberra proposed masterplan. These lanes are needed irrespective of the development yield between the ranges of 1200 and 2100 dwellings for the total Lawson Development However the demand for 6 lanes appears to be very highly influenced by the proposed developments at the University of Canberra. The options for the development with the University of Canberra will require detailed assessment, particularly with regard to the scale of the development and the connections to the external road network. The intersection of Maribyrnong Avenue (south) Baldwin Drive will require widening by one lane on Baldwin Drive. Note traffic signals have been selected to provide for the safe movement of pedestrians (school children and bus passengers) across Baldwin Drive. Revision B 16 January 2009 Page 26
2.5 Road Cross Sections 2.5.1 External Roads The existing bridge across Lake Ginninderra provides a travelled path of approximately 11.0 metres. This provides sufficient space for three 3.4m lanes plus a 0.4m shoulder / clearance to the bridge barrier. However this lane arrangement will require cyclists to use the adjacent shared path - in exactly the same way as occurs on Commonwealth and Kings Avenues. 2.5.2 Internal Roads The two key internal roads will need to provide for possible bus routes from the extension of Aikman Drive to Maribyrnong Avenue (South) and the proposed extension of Allawoona Street from the University of Canberra. The forecast internal traffic flows indicate that for a development of 1500 dwellings a total of about 10,500 trips will be generated. These will be reasonably uniformly spread over the three links connecting to the external network indicating that it is likely that traffic levels will possibly be in the order of 4,000 vpd on the main link between Aikman Drive extension and Maribyrnong Avenue. All three proposals provide for medium density development on the approaches to the major roads and hence the expectation is that these traffic levels will be well within those An indication of possible traffic flows at the development connections to the external network are shown below in Figure 2-6. Figure 2-6 Indicative future internal traffic flows 2.6 Public Transport The concept plans provide for the opportunity to contain all of the site within a 400m radius of either one or two internal bus routes or an existing external bus route. The extension of the access into the University of Canberra provides a good opportunity to connect these two developments with public transport whilst the extension of the bus route from Maribyrnong Avenue (south) to Aikman Drive provides an opportunity for a direct connection to the Belconnen Town Centre. Revision B 16 January 2009 Page 27
In addition it is understood that the public transport planning currently being undertaken for the ACT government proposes a high frequency bus service along Ginninderra Drive that will be able to service Lawson. These concepts are shown below. Figure 2-7 Indicative public transport network 2.7 Pedestrian and Cyclists Network The primary cycle network will be a system along the foreshore of Lake Ginninderra. In addition the trunk network along Ginninderra Drive for both on and off road cycling is expected to be maintained. Secondary connections will be possible along Reedy Creek and also the boundary between the Defence land and ACT government land. Footpaths will provide connections to Maribyrnong Avenue, Allawoona Street and Aikman Drive. Revision B 16 January 2009 Page 28
3.0 Conclusions The proposed development of Lawson is quite close to the Belconnen Town Centre and the University of Canberra thus potentially generating a higher proportion of walk and cycle trips than would be the case for developments further removed from this central location. There are various possible scheme for the development but all have common access opportunities of extending Aikman Drive, Alawoona Street or Maribyrnong Avenue (south). These connections provide for appropriate permeability into the development, the opportunities for two internal bus routes and being sufficiently circuitous to not attract through traffic. The future traffic flows indicate that there will be a need to widen Ginninderra Drive to 3 lanes in each direction: primarily to meet the demands from a growing Gungahlin and west Belconnen. The timing of this widening needs to be considered from an assessment of the competing road space needs as identified from strategic modelling and scenario testing. Revision B 16 January 2009 Page 29