Hobsonville Corridor Precinct
Technical Transportation Assessment
June 2017
Project: Hobsonville Corridor Precinct Title: Technical Transportation Assessment Document Reference: P:\ATSP Auckland Strategy and Policy\062 Transport Assessment, Spine Road, Hobsonville Business Area\4.0 Reporting\R1A170620.docx Prepared by: Qing Li, Angie Crafer Project Manager Angie Crafer Reviewed by: Angie Crafer Revisions: Date Status Reference Approved by Initials 28 June 2017 A R1A170620 A Crafer
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Hobsonville Corridor Precinct Technical Transportation Assessment i
EXECUTIVE SUMMARY
Flow Transportation Specialists Ltd has been engaged by Auckland Transport to provide transport planning and traffic engineering advice on the transport network associated with the Hobsonville Corridor Precinct. Traffic models have been developed to assess the potential impacts of a completed “Spine Road” on the surrounding transport network.
Relative to the Do Minimum scenario without the complete Spine Road, a scenario with a completed Spine Road is predicted to result in a number of key, strategic transportation benefits, including the following: Improved network resilience. A completed Spine Road provides an alternative main route running in parallel to Hobsonville Road. This will result in network resilience benefits when either Hobsonville Road or SH18 are subject to temporary or unplanned closures or restrictions, or during an extreme traffic event. Improved connectivity. A connected Spine Road will provide improved connectivity within the precinct, and remove the need for all trips to use Hobsonville Road. This improved connectivity will benefit general traffic, pedestrians and cyclists, and potentially public transport users should some bus services use the Spine Road. Reduced traffic on Hobsonville Road. The proposed Spine Road is predicted to have significantly lower traffic volumes on Hobsonville Road than with an incomplete Spine Road, and this will lead to reduced conflict with existing vehicle crossings on the south side of this street. This in turn may provide greater redevelopment potential on the south side of this corridor, which is zoned Mixed Housing Urban within the AUP (OiP). The reduced traffic volumes on this corridor would also lead to the three following key strategic benefits. Improved opportunities for bus priority measures on Hobsonville Road. Lower general traffic on Hobsonville Road with the completed Spine Road scenario will provide greater opportunities for additional lanes on this road to be dedicated to public transport, facilitating this corridor’s proposed FTN status. The lower traffic volumes will additionally improve pedestrian accessibility to this public transport corridor, as below. Improved walking and cycling environment on Hobsonville Road. The lower traffic volumes on Hobsonville Road will in general improve the walking and cycling environment on this corridor, and reduce conflict between active mode users and traffic. The reduced traffic will additionally allow more opportunities for safe crossing locations of this road, better connecting the residential catchment on the south/east side of the road with employment on the north/west side, as well as connecting users to bus stops. Reduced severance to Hobsonville Primary School. Related to the walking and cycling effects above but requiring special mention, Hobsonville Primary School is severed from its existing residential catchment by Hobsonville Road, and safe crossing opportunities for school children are limited to signalised crossings. The reduced traffic on Hobsonville Road that the completed Spine Road provides will result in reduced conflict between pedestrians and vehicles, as well as improved opportunities for additional safe crossings.
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Three different connection options for the eastern end of the complete Spine Road scenario have been considered. The analysis of these options has identified that they will result in similar effects on the road network within the Hobsonville Corridor Precinct, provided that the identified transport provisions can be provided at connections on Brigham Creek Road at the SH18 interchange.
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CONTENTS 1 INTRODUCTION ...... 1 2 ASSESSMENT METHODOLOGY ...... 2 Study Objectives ...... 2 Traffic Model ...... 3 Hobsonville Corridor Precinct Network Assumptions ...... 3 Do Minimum Network Assumptions ...... 3 Modelled Spine Road Network ...... 5 Hobsonville Corridor Precinct Land Use Assumptions and Vehicle Trip Rates ...... 8 3 TRANSPORT ASSESSMENT ...... 10 Traffic Flows ...... 12 Strategic Transport Benefits of the Spine Road ...... 16 Transportation Effects of a Completed Spine Road ...... 17 Effects on Public Transport, Pedestrians and Cyclists ...... 17 Effects on General Traffic ...... 18 Transport effects on the existing Hobsonville Primary School ...... 19 Connectivity Implications of Spine Road Options ...... 20 Connections to the eastern side of Brigham Creek Road ...... 20 Connecting the Spine Road to Brigham Creek Road at the SH18 off-ramp roundabouts ...... 20 Conclusions ...... 21
APPENDICES
APPENDIX A PREDICTED TRAFFIC VOLUMES APPENDIX A ASSESSMENT OF SPINE ROAD OPTIONS APPENDIX C SIDRA LAYOUTS
Hobsonville Corridor Precinct Technical Transportation Assessment 1
1 INTRODUCTION
Flow Transportation Specialists Limited (Flow) has been commissioned by Auckland Transport to provide transport planning and traffic engineering advice in relation to a technical assessment of the impacts on the existing road network in relation to development to the north of Hobsonville Road within the Hobsonville Corridor Precinct, and the provision of a Spine Road as proposed in Plan Change 14 to the Auckland Council Plan - Waitakere Section (“PC14”). The indicative road network from PC14 is shown in the Hobsonville Corridor Precinct Plan that was included in the Proposed Auckland Unitary Plan (“PAUP”), as shown in Figure 1 below; however, this was not carried forward into the Auckland Unitary Plan – Operative in Part (“AUP (OiP)”).
Figure 1: Precinct Plan 1: Hobsonville Corridor Precinct Plan in the PAUP
The area comprises approximately 70 ha of land between Hobsonville Road, SH18 and Brigham Creek Road that is predominantly zoned Business – Light Industry and is potentially able to be subdivided under the provisions of Section E38 Subdivision of the AUP (OiP) into sites that are 1,000 to 2,000 m2 in net area; with a 20 m wide frontage. The provisions also enable provision of entrance and accessways to service rear sites with minimum widths and lengths provided for these access ways. Through the process of subdivision all new sites will potentially have vehicle access to either the existing public road network (subject to vehicle access standards in Sections E38 and E27 Transport) or new roads constructed as part
Hobsonville Corridor Precinct Technical Transportation Assessment 2 of any subdivision. There is guidance in Section E38 in relation to the provision of new roads but it is not clear that it will result in the delivery of a completed Spine Road as indicated in PC14 and deliver the benefits that a completed Spine Road was expected to provide.
It is also noted that the northern side of Hobsonville Road is a Limited Access Road and Brigham Creek Road has a Vehicle Access Restriction Control (Motorway Interchange Control) under the AUP (OiP) on both sides of the road.
Some development in the area has already occurred, and this has included the vesting of a 250 m section of the Spine Road and new local roads in the vicinity of Hobsonville Primary School.
The assessment reported on here focusses on the impacts of a completed Spine Road on the transport functions, particularly network resilience and connectivity of the existing road network, including SH18, and also on the proposed roads in Whenuapai as part of proposed Plan Change 1 to the Auckland Unitary Plan. The assessment has made use of the traffic model developed for the Whenuapai proposed Plan Change Stage 1 technical transportation assessment.
2 ASSESSMENT METHODOLOGY
Study Objectives
The objectives of the assessment include the following: Identifying the potential effect of leaving subdivision of the remaining land to occur without any provision to deliver the Spine Road Identifying the potential effect of providing the Spine Road, such as considering the following: . transport effects relating to connecting the Spine Road to Brigham Creek Road at the SH18 off-ramp roundabout . transport effects of the Spine Road in relation to the Hobsonville Corridor Precinct connection to the eastern side of Brigham Creek Road . transport effects of the Spine Road on the anticipated public transport network and walking and cycling along Hobsonville Road . transport effects of providing the Spine Road on Hobsonville Primary School and potential impacts of surrounding developments accessing Hobsonville Road from only the parts of the Spine Road that have currently been formed
Traffic models being used to assess transport investment decisions for Whenuapai have been used to provide information to help inform the assessments. These models are considered to be appropriate for a high level assessment, for example, determining expected traffic volumes associated with different scenarios. Much of the assessment is qualitative, for example considering the transport effects of providing an incomplete Spine Road.
The remainder of the internal road network shown in PC14 and the PAUP are excluded from this assessment; however, it is noted that such an internal road network should be able to be provided through plan provisions, which will help to reduce the need for vehicle crossings and associated access
Hobsonville Corridor Precinct Technical Transportation Assessment 3 ways for rear sites on to Hobsonville Road and will better support a walkable and connected neighbourhood.
Traffic Model
The SATURN models developed for the Stage 1 technical assessment for the proposed Whenuapai Plan Change have been used in this study to help assess the transportation impacts of the Spine Road shown in PC14 and the PAUP. The SATURN models were originally developed for the Transport for Future Growth Area (TFGA) study for the Northwest Area, and were later used in the development of transport and zoning provisions and the Integrated Transport Assessment (“ITA”) for the Whenuapai Structure Plan in mid-2016 and the Whenuapai proposed Plan Change Stage 1 assessment in July 2017. For this study, the same land use and transport provisions assessed for the Whenuapai proposed Plan Change Stage 1 technical assessment have been assumed.
The SATURN models include background traffic representing years 2021 and 2026 as informed by the Auckland Regional Transport (“ART”) model and the Whenuapai proposed Plan Change model assumptions. The ART model assumes a land use scenario named Scenario I10, which is in line with the Future Urban Land Supply Strategy (“FULSS”). We understand that at the time of the modelling, the land uses projected in the FULSS are preliminary estimate figures and will be updated later this year. For the Hobsonville Corridor Precinct proposed Plan Change area, the land use and transport improvements are consistent with the transport provisions included in the recently completed Whenuapai proposed Plan Change Stage 1 Transport Assessment report (June 2017).
In additional, SIDRA intersection models have been developed for key intersections to help guide how the Spine Road can be connected at its eastern end. It should be noted that the traffic modelling completed for this assessment is at a high level; more detailed micro-simulation modelling may be required to assess the detailed layout of proposed intersections.
Hobsonville Corridor Precinct Network Assumptions
The traffic models include a preliminary road network within the Hobsonville Corridor Precinct proposed Plan Change based on the PAUP Hobsonville Corridor Precinct Plan.
Hobsonville Road and Brigham Creek Road are designated as Arterial Roads in the AUP (OiP), and Section E27 states that access will be restricted or managed to and from sites on arterial roads to provide for the efficient movement of people and goods on the road network. When Hobsonville Road was vested with Auckland Transport by the NZ Transport Agency, its Limited Access Road restriction along the northern side of the road was retained. While the Transport Agency website indicates that where access to a local road isn’t practicable then minimal numbers of safe accesses can be located on the LAR, for the purposes of this assessment, for all options considered, vehicles have been assumed to gain access to the precinct through the local roads joining Hobsonville Road.
Do Minimum Network Assumptions
A network scenario that assumes the existing developed network without the delivery of the full Spine Road has been assessed. At the time of the assessment, several roads have already been constructed in
Hobsonville Corridor Precinct Technical Transportation Assessment 4 the precinct; these include Westpoint Drive (part of the Spine Road), Dowdens Lane, Workspace Drive and Rawiri Place, based on the aerials shown on the Auckland Council’s GEOMAPS website1. Of these, Westpoint Drive and Dowdens Lane have been included in the traffic models as well as a new road south of Dowdens Lane to accommodate traffic in the southern area of the Hobsonville Corridor Precinct. These roads are shown in Figure 2Error! Reference source not found..
Figure 2: Do Minimum Road Network
The modelled network is shown in Figure 3 below. This scenario has been referred to in this report as the Do Minimum. Of note is that the road joining Brigham Creek Road from the Hobsonville Corridor Precinct north of Brigham Creek Road has been assumed to be a left in left out priority controlled intersection.
1 https://geomapspublic.aucklandcouncil.govt.nz/viewer/index.html
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Figure 3: Modelled Do Minimum Road Network
Modelled Spine Road Network
A scenario that assumes the Spine Road through the Hobsonville Corridor Precinct connecting between Hobsonville Road/Westpark Drive and the SH18/Brigham Creek Road interchange has been considered, as shown in Figure 4.
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Figure 4: Spine Road Network
Three options have been tested for the road network that includes the Spine Road, with these including different connections with Brigham Creek Road and Hobsonville Road at the eastern end of the Spine Road. These are described as follows: Option 1: includes the Spine Road connecting to Brigham Creek Road at the SH18 southbound off-ramp roundabout, as shown in the PC14 and PAUP plans Option 2: includes the Spine Road connecting to Brigham Creek Road at the SH18 southbound on-ramp roundabout Option 3: includes the Spine Road connecting to a new road link that extends from the Brigham Creek Road/SH18 southbound on-ramp roundabout to a new intersection on Hobsonville Road
The modelled networks for these options are shown in the following figures. As with the Do Minimum, all these options assume a left in left out priority intersection on Brigham Creek Road connecting to the precinct to the north of Brigham Creek Road.
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Figure 5: Modelled Road Network including the Spine Road – Option 1
Figure 6: Modelled Road Network including the Spine Road – Option 2
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Figure 7: Modelled Road Network including the Spine Road – Option 3
Hobsonville Corridor Precinct Land Use Assumptions and Vehicle Trip Rates
As discussed previously, the land use assumptions with regard to the future development in Northwest Auckland are guided by the ART land use Scenario I10. In ART, the Hobsonville Corridor and Hobsonville Village areas are included in Zone 417, which also includes the area assumed as Stage 1a in the Whenuapai proposed Plan Change area, as shown in Figure 8.
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Figure 8: ART Zone Map – Zone 147
Based on the land use proposed in Scenario I10, some 1,250 and 1,850 jobs are assumed to be located within Zone 147 in years 2021 and 2026 respectively. It is anticipated in the Whenuapai proposed Plan Change that development in Stage 1a will be mainly residential; therefore these jobs have been assumed to be located within the Hobsonville Village and Corridor areas only. In addition, it is noted that Hobsonville Village has already been largely developed. The land use assumptions in ART indicate that the predicted number of jobs within Hobsonville Village is some 300 jobs, based on the employment assumed in Zone 147 in the 2013 and 2016 models. Therefore, the total number of jobs in the Hobsonville Corridor Precinct is assumed to be 1,000 and 1,550 for 2021 and 2026 respectively. This matches the information provided by Auckland Transport, where up to some 1,4002 jobs are assumed could occur in the Hobsonville Corridor Precinct.
As well as these jobs, a primary school is also located within the Hobsonville Corridor Precinct.
A peak hour vehicle trip rate of 0.5 trips per job has been assumed for the Hobsonville Corridor Precinct. The total number of students in the Hobsonville Primary School is assumed to be 300 in 2021 and 8003 in 2026. For school traffic, it is assumed that for each primary school student 0.4 vehicle trips will be generated in the morning peak (AM) hour, with a trip rate of 0.2 vehicle trips per student being assumed
2 Based on an evaluation undertaken by Stantec (Adam Jellie, 14 June 2017), based on the Market Economics report “Land Demand by Activity and PAUP Supply”, March 2016 3 Based on Whenuapai Plan Change Land use and 0.3 Students per dwelling ratio, as suggested by the Ministry of Education formula relative to population growth
Hobsonville Corridor Precinct Technical Transportation Assessment 10 in the evening peak (PM). These assumptions are consistent with the ones used for the Whenuapai proposed Plan Change Stage 1 assessment.
Table 1: Predicted Peak Hour Vehicle Trip Generation
2021 2026 Roll/FTE AM Hour PM Hour Roll/FTE AM Hour PM Hour Hobsonville Primary 300 120 60 800 320 160 School Light Industrial 1,000 500 500 1,550 775 775
Based on the daily trip generation ratios suggested in Guide to Traffic Generating Developments4 (RTA Guide), a total of some 5,000 and 8,000 trips per day are predicted to be generated by the Hobsonville Corridor Precinct in the modelled years 2021 and 2026. Of these trips, approximately 20% are predicted to be to/from the North Shore, about 30% to/from Auckland Central, and the rest of the trips to/from areas to the west or distributed to/from Northwest Auckland development areas, based on the predicted trip distribution in the ART model.
Assumptions have been made within the model that there will be some trip chaining, where for example a parent may drop a student at school and then proceed to their work place elsewhere, and these trips have subtracted from the home to work trips to avoid double counting.
The above traffic demands assumed with the Hobsonville Corridor Precinct have been assessed with the following background traffic scenarios: 2021: assumes the 2021 background traffic informed by ART Scenario I10, together with planned and constructed Whenuapai Special Housing Area developments. Transport provisions for surrounding areas, including for public transport, are consistent with the infrastructure improvements identified in the Whenuapai proposed Plan Change Stage 1, Base Scenario5 2026: assumes the 2026 background traffic informed by ART Scenario I10, together with the proposed land use developments and transport provisions included in the Whenuapai proposed Plan Change Stage 1, Scenario 2Error! Bookmark not defined., including development in Whenuapai Stages 1a, 1b, 1, 1d, 1e and 2.
3 TRANSPORT ASSESSMENT
A discussion around the transport effects of leaving the subdivision of remaining land to occur without the connecting Spine Road compared to including the full Spine Road is provided in this section.
4 Based on Section 3.10.2, Warehouses, RTA guide, daily vehicle trips = 4 per 100 m² GFA 5 The “Base Scenario” includes existing primary schools at Whenuapai and Hobsonville; 2,000 dwellings in Whenuapai including 850 existing outside future urban zone and 1,150 consented dwellings located either side of Totara Road between Brigham Creek Road and Dale Road; and no new business activity within Whenuapai. Source: Whenuapai Plan Change, Stage 1 Technical Assessment, Flow Transportation Specialists Ltd, June 2017
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An assessment of the modelled outputs has included consideration of capacity in relation to the predicted traffic volumes. Level of service (“LOS”) is typically used to qualitatively describe the operating conditions of a traffic network, based on factors such as speed, delay, degree of saturation or a combination of these. The level of service is designated with a letter A to F, where “A” represents the best operating conditions, and “F” represents the worst operating conditions. Considerations relating to access and network connectivity have also been considered in determining what transport provisions are required. While this process appears to address vehicular traffic only, inherent assumptions regarding trip generation mean that appropriate public transport services and pedestrian and cyclist facilities need to be provided; otherwise higher vehicle trip rates need to be applied.
The RTA Guide6 provides Levels of Service (LOS) for differing traffic flows on urban roads, which range from LOS A (free flow) to LOS F (very congested). For highways, the Highway Capacity Manual7 (HCM) suggests that a multilane highway exceeds LOS D at around 1,920 vehicles per hour per lane.
Table 2: Road Midblock Level of Service
Level of Service Two Lane Urban Road Four Lane Urban Road Multilane Highways (RTA Guide) (RTA Guide) (HCM) veh/hr/lane veh/hr/two lanes veh/hr/lane A 0 to 200 0 to 900 0 to 670 B 201 to 380 901 to 1,400 671 to 1,050 C 381 to 600 1,400 to 1,800 1,051 to 1,500 D 601 to 900 1,801 to 2,200 1,501 to 1,920 E 901 to 1,400 2,201 to 2,800 1,920 to 2,100 F >1,400 >2,800 >2,100
Section 4 of the Draft Auckland Transport Code of Practice (ATCoP) also provides general guidance on the number of lanes required on all roads within the Auckland Region. It suggests that for a Local or Collector Road, a two lane road can generally support an Annual Average Daily Traffic (AADT) of 5,000 vehicles per day (approximately 500 per hour during the commuter peaks) and a four lane road can accommodate up to 10,000 vehicles per day (1,000 vehicles per hour in peak). For an Arterial Road, it suggests that a four lane road can support up to 25,000 vehicles per day, which is approximately 2,500 vehicles per peak hour. The suggested maximum volumes from ATCoP would result in a LOS C (two lane) and LOS B (four lane) on local roads and LOS E on four lane arterial roads.
LOS D has been used as the target to be achieved for intersections and local road links. LOS D delay is typical of many urban roads during peak traffic times in much of Auckland. It is noted that providing “too much” capacity can have an adverse effect on the success of measures that are anticipated to help achieve reduced travel by single occupant cars and accordingly, while a LOS of D has been the target, LOS D/E may be considered to be appropriate in some instances, and has been assumed as adequate for peak direction peak hour situations.
6 Table 4.4, Urban Road Peak Hour Flows Per Direction, Guide to Traffic Generating Developments (RTA), October 2002 7 Exhibit 21-2, LOS Criteria for Multilane Highways, Highway Capacity Manual
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Traffic Flows
Traffic flows generated by the precinct are anticipated to be 5,000 to 8,000 vehicle trips per day, based on the trip generation described in Section 3 above.
The following table provide the predicted traffic volumes about the Hobsonville Corridor Precinct area, with snapshots from the models of predicted traffic flows in the vicinity of the Hobsonville Corridor Precinct included in Appendix A of this report, for the 2026 morning and evening peak periods. Vehicles per day have been estimated based on a combination of 5 times morning plus 5 times evening peak hour flows.
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Table 3: Summary of Predicted Traffic Flows on Key Roads
Location Do Minimum Network Completed Spine Road Network Option 1 Option 2 Option 3 AM PM Hour Vehicles AM PM Hour Vehicles AM PM Hour Vehicles AM PM Hour Vehicles Hour per Day Hour per Day Hour per Day Hour per Day SH18, north of Brigham Creek Road 7,350 8,650 80,100 7,400 8,550 79,750 7,400 8,550 79,750 7,400 8,550 79,650 SH18, south of Brigham Creek Road 6,500 7,700 71,150 6,550 7,750 71,600 6,500 7,800 71,550 6,500 7,800 71,400 Hobsonville Road between Westpark 1,400 1,600 14,950 900 1,400 11,350 850 1,300 10,900 950 1,350 11,550 Drive and Marina View Road Hobsonville Road, between Dowdens 1,000 1,250 11,450 500 1,100 8,100 500 1,150 8,250 800 1,250 10,000 Lane and Suncrest Drive Hobsonville Road, between Suncrest 900 1,100 10,000 250 300 2,650 250 300 2,950 300 450 3,600 Drive and Brigham Creek Road Brigham Creek Road, west of Hobsonville 2,000 2,950 24,750 1,550 2,100 18,250 1,550 1,950 17,600 1,500 1,850 16,700 Road Dowdens Lane 500 350 4,150 100 100 950 100 100 850 100 100 900 Spine Road, between Westpark Drive and N/A N/A N/A 450 300 3,850 450 350 4,050 400 300 3,450 Marina View Road Extension Westpoint Drive, between Dowdens Lane 400 200 3,100 900 400 6,650 1,000 500 7,400 700 400 5,550 and Suncrest Drive Spine Road, between Suncrest Drive N/A N/A N/A 1,100 1,100 10,950 1,150 1,250 12,000 1,200 1,450 13,200 Extension and Brigham Creek Road New Link between Spine Road and N/A N/A N/A N/A N/A N/A N/A N/A N/A 750 950 8,400 Hobsonville Road
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The information is graphically shown in the following figures, with separate graphs for the volumes on SH18, which would otherwise distort the scale in relation to the volumes.
Figure 9: Predicted Morning Peak Hour Volumes on roads in the vicinity of the Hobsonville Corridor Precinct with the options tested
2,500
Do Min AM Op1 AM Op2 AM Op3 AM
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0 Hobsonville Hobsonville Hobsonville Brigham Creek Dowdens Lane Spine Road, Westpoint Spine Road, New Link Road between Road, between Road, between Road, west of between Drive, between between between Spine Westpark Drive Dowdens Lane Suncrest Drive Hobsonville Westpark Drive Dowdens Lane Suncrest Drive Road and and Marina and Suncrest and Brigham Road and Marina and Suncrest Extension and Hobsonville View Road Drive Creek Road View Road Drive Brigham Creek Road Extension Road
Figure 10: Predicted Evening Peak Hour Volumes on roads in the vicinity of the Hobsonville Corridor Precinct with the options tested 3,500 Do Min PM Op1 PM Op2 PM Op3 PM 3,000
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0 Hobsonville Hobsonville Hobsonville Brigham Creek Dowdens Lane Spine Road, Westpoint Spine Road, New Link Road between Road, between Road, between Road, west of between Drive, between between between Spine Westpark Drive Dowdens Lane Suncrest Drive Hobsonville Westpark Drive Dowdens Lane Suncrest Drive Road and and Marina and Suncrest and Brigham Road and Marina and Suncrest Extension and Hobsonville View Road Drive Creek Road View Road Drive Brigham Creek Road Extension Road
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Figure 11: Predicted Peak Hour Volumes on SH18, either side of the Brigham Creek Road interchange
10,000 Do Min AM Op1 AM Op2 AM Op3 AM Do Min PM Op1 PM Op2 PM Op3 PM 9,000
8,000
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0 SH18, north of Brigham Creek Road SH18, south of Brigham Creek Road An assessment of the model outputs identifies the following. With the Do Minimum network, traffic demands generated by the Hobsonville Corridor Precinct will use Hobsonville Road and Brigham Creek Road to access the state highway network. With the predicted traffic in 2026, Brigham Creek Road (south of SH18) will carry approximately 25,000 vehicles per day, with peak directional traffic being predicted as 1,200 and 1,750 per hour in the morning and evening peaks respectively. Based on the LOS criteria suggested by the RTA, LOS F will be experienced on Brigham Creek Road between the SH18 southbound off-ramp and Settlers Avenue during the evening peak unless additional capacity is provided. All of the completed Spine Road options are predicted to have lower traffic flows on Hobsonville Road and Brigham Creek Road compared to the Do Minimum, with options 1 and 2 expected to have lower volumes on Hobsonville Road compared to option 3, and option 3 expected to have lower volumes on Brigham Creek Road compared to options 1 and 2. Peak hour traffic volumes on Brigham Creek Road east of SH18 are predicted to be in the order of 1,250 vehicles per hour in the eastbound direction and 900 vehicles per hour in the westbound direction with Option 1; 1,250 vehicles per hour in the eastbound direction and 900 vehicles per hour in the westbound direction with Option 2; and 1,200 vehicles per hour in the eastbound direction and 800 vehicles per hour in the westbound direction with Option 3. Based on a LOS no worse than D/E, additional capacity will be needed to accommodate the expected 2026 volumes with all completed Spine Road options in the eastbound direction; however no widening is considered to be necessary in the westbound direction in 2026. A T-intersection has been suggested in Option 3 at the intersection of the Spine Road and the new road link between the SH18 southbound on-ramp intersection and Hobsonville Road, with priority assumed for the through movements on the new connection. As such, the new link proposed in Option 3 will provide a shorter connection between Hobsonville Road and Spine Road, therefore
Hobsonville Corridor Precinct Technical Transportation Assessment 16
attracting some traffic onto Hobsonville Road with more traffic on Hobsonville Road south of the new connection than with options 1 and 2. It is predicted that the link will carry a peak hour volume of approximately 900 vehicles per hour, which, when considering the flows along Hobsonville Road, will require traffic signals at the Hobsonville Road/New Connection Road intersection. Scenarios that include the completed Spine Road are predicted to have a negligible impact on the volume of traffic on SH18, with the changes between the options and the Do Minimum being around 1 percent. The predicted traffic demands on Dowdens Lane are lower with the completed Spine Road options compared with the Do Minimum network, in the order of 70 to 80% less. Accordingly, a scenario with the completed Spine Road will experience less pedestrian/vehicle interference near the Hobsonville Primary school pick up/drop off zone on Dowdens Lane and the operation of the Hobsonville Road/Dowdens Lane intersection will be better, providing a safer environment for pedestrians and cyclists as well as vehicle occupants. The traffic volumes on Westpoint Drive between Suncrest Drive and Dowdens Lane are predicted to be approximately 3,100 vehicles per day with the Do Minimum network. If the full length of the Spine Road is constructed, the traffic volumes on this road section are predicted to more than double with options 1 and 2 and almost double with Option 3, due to the traffic from the southern parts of the precinct (approximately 4,000 vehicles per day) using the Spine Road to get to and from the SH18 Brigham Creek Road interchange. For the Spine Road section between Suncrest Drive and Brigham Creek Road, daily traffic volumes of approximately 11,000, 12,000 and 13,200 vehicles per day are predicted with options 1, 2 and 3 respectively. As well as accommodating precinct related traffic, this increase is also attributable to some general traffic on Hobsonville Road using the Spine Road to travel between Westpark Drive extension, Marina View Road extension and Suncrest Road to and from the SH18 Brigham Creek Road interchange, due to these being shorter routes.
Strategic Transport Benefits of the Spine Road
Relative to the Do Minimum scenario, all three connection options for the completed Spine Road are predicted to result in a number of key, strategic transportation benefits, including the following: Improved network resilience. A completed Spine Road provides an alternative main route running in parallel to Hobsonville Road. This will result in network resilience benefits when either Hobsonville Road or SH18 are subject to temporary or unplanned closures or restrictions, or during an extreme traffic event. Improved connectivity. A connected Spine Road will provide improved connectivity within the precinct, and remove the need for all trips to use Hobsonville Road. This improved connectivity will benefit general traffic, pedestrians and cyclists, and potentially public transport users should some bus services use the Spine Road. Reduced traffic on Hobsonville Road. A completed Spine Road scenario is predicted to have significantly lower traffic volumes on Hobsonville Road than the Do Minimum, and this will lead to reduced conflict with existing vehicle crossings on the south side of this street. This in turn may
Hobsonville Corridor Precinct Technical Transportation Assessment 17
provide greater redevelopment potential on the south side of this corridor, which is zoned Mixed Housing Urban within the AUP (OiP). The reduced traffic volumes on this corridor would also lead to the three following key strategic benefits. Improved opportunities for bus priority measures on Hobsonville Road. Lower general traffic on Hobsonville Road will provide greater opportunities for additional lanes on this road to be dedicated to public transport, facilitating this corridor’s proposed FTN status. The lower traffic volumes will additionally improve pedestrian accessibility to this public transport corridor, as below. Improved walking and cycling environment on Hobsonville Road. The lower traffic volumes on Hobsonville Road will in general improve the walking and cycling environment on this corridor, and reduce conflict between active mode users and traffic. The lower traffic volumes will additionally allow more opportunities for safe crossing locations of this road, better connecting the residential catchment on the south/east side of the road with employment on the north/west side, as well as connecting users to bus stops. Reduced severance to Hobsonville Primary School. Related to the walking and cycling effects above but requiring special mention, Hobsonville Primary School is severed from its existing residential catchment by Hobsonville Road, and safe crossing opportunities for school children are limited to signalised crossings. The lower traffic volumes on Hobsonville Road that a completed Spine Road provides will result in reduced conflict between pedestrians and vehicles, as well as improved opportunities for additional safe crossings.
The latter three benefits above in turn will assist in reducing overall private car travel demands within the Hobsonville Corridor Precinct, as well as within the existing West Harbour residential area.
These and other issues are discussed in further detail in the following sections.
Transportation Effects of a Completed Spine Road
Effects on Public Transport, Pedestrians and Cyclists
With the Do Minimum and completed Spine Road scenarios it has been assumed (as per the Whenuapai Structure Plan), that Frequent Transit Network (FTN) services and priorities will be provided along Hobsonville Road by 2026 and Rapid Transit Network (RTN) services and facilities will be provided along SH16 and SH18 by 2036. The facilities along Hobsonville Road are anticipated to include upgraded intersections, wider footpath and cycleways, according to Auckland Transport’s Northwest Transformation Project8.
Without the full Spine Road, traffic volumes in the region of 750 to 1,000 vehicles per hour in 2026 are predicted along the section of Hobsonville Road between Trig Road and Dowdens Lane during peak times. This may require road widening along Hobsonville Road to provide priority for public transport (bus lanes or transit lanes) as well as providing a safer and more attractive environment for pedestrians and cyclists. These volumes relate to a level of service of “D” or “E”, which typically means the traffic
8 https://at.govt.nz/projects-roadworks/northwest-transformation/, Auckland Transport (retrieved in July 2017)
Hobsonville Corridor Precinct Technical Transportation Assessment 18 volumes are close to capacity and vehicles are restricted to select their desired speed and to manoeuver within the traffic stream. Without priority lanes for public transport, buses will use the same lanes as other traffic, making public transport less attractive. Unless public transport and walking and cycling travel modes are made viable and attractive options, the private vehicle trip generation is likely to be greater than anticipated, resulting in increased delays for all road users.
As discussed in Section 3.1 above, including the full length of the Spine Road will result in lower traffic volumes along Hobsonville Road than with the Do Minimum scenario, therefore reducing the need to include additional general traffic lanes along Hobsonville Road and at key intersections. Instead, bus priority lanes could be provided along Hobsonville Road and this may further reduce the vehicle trips generated in the area due to the increased attractiveness of bus services. In addition, as the Spine Road provides a route through the precinct, additional local bus services could be provided on the Spine Road providing greater access to public transport and encouraging the use of public transport.
Effects on General Traffic
Traffic generated by the business and industrial developments within the Hobsonville Corridor Precinct will increase the number of cars and Heavy Commercial Vehicles (HCVs) directly accessing and using Hobsonville Road. Hobsonville Road is defined as an Arterial in the AUP (OiP) and the Regional Arterial Road Plan (RARP) has identified that the road is expected to carry private vehicles, heavy motor vehicles, passenger transport vehicles and serve as an important cycle link across Upper Harbour. The greater increase in traffic associated with the Do Minimum network compared to the Spine Road network will increase traffic delays during peak times for all road users and could result in safety concerns along the Hobsonville Corridor if appropriate walking and cycling facilities are not provided.
In addition, the increased vehicle traffic on Hobsonville Road will increase the delays experienced by pedestrians crossing Hobsonville Road, as more green time will be consumed by vehicle movements at signalised intersections. This may in turn reduce the viability of walking trips within the Hobsonville Corridor area and increase the vehicle trip generation in the area.
With the Do Minimum modelled road network, an assessment of model outputs indicates that the Hobsonville Road/Dowdens Lane/Hendrika Court signalised intersection will be inadequate to accommodate the predicted traffic on Dowdens Lane in 2026. At the moment, only one approach lane is provided on the Dowdens Lane approach at the intersection and this is predicted to result in Level of Service F during the morning and afternoon peak periods, with the full development of the Hobsonville Corridor Precinct. The modelling predicts that with high delays on Dowdens Lane, traffic generated within the precinct would re-route via the Suncrest Drive/Hobsonville Road roundabout to access Hobsonville Road.
Traffic flows along Brigham Creek Road east of the SH18/Brigham Creek Road interchange are predicted to be high in the Do Minimum scenario, with modelled flows of some 1,750 vehicles per hour in the peak direction. This volume of traffic is equivalent to a level of service F, and widening would be required on Brigham Creek Road and at the Brigham Creek Road/Hobsonville Road intersection to accommodate traffic flows and public transport priority.
Hobsonville Corridor Precinct Technical Transportation Assessment 19
The completed Spine Road will provide a more direct route between the Hobsonville Corridor Precinct and the State Highway network. A connection between the Spine Road and the SH18/Brigham Creek Road Interchange will provide travel time and travel distance savings for freight and private vehicles, therefore improving the economic efficiency of the Hobsonville Corridor Precinct.
A completed Spine Road will provide additional route choice for traffic generated by existing and future development within the Hobsonville Corridor Precinct. This is considered to provide more resilience to the transport network, making it easier to cope with unexpected situations. Equally though, the Spine Road may be used by those travelling between the SH18/Brigham Creek Road interchange and locations other than the Hobsonville Corridor Precinct as it is likely to provide a faster route than travelling along Hobsonville Road. This has benefits to those on Hobsonville Road, but may not be seen as desirable by those located on the Spine Road.
As discussed in Section 3.1, the network with the completed Spine Road is predicted to have lower traffic volumes on the eastern section of Brigham Creek Road than with the Do Minimum network, due to the Spine Road providing a connection that allows a bypass of this section of Brigham Creek Road. Lower traffic volumes are also predicted on Hobsonville Road between Brigham Creek Road and Suncrest Drive with the Spine Road network. As such, less road widening (only in the eastbound direction) may be required on Brigham Creek Road.
The Whenuapai Structure Plan and proposed Whenuapai Plan Change include the future extension of Marina View Road to Spedding Road to the north of SH18, with a connection with the Spine Road within the Hobsonville Corridor Precinct. This will provide another connection between Hobsonville Road and Spine Road, and also provide a quicker route between the Hobsonville Corridor Precinct and the West Harbour Ferry Terminal. Accordingly, the proposed Plan Change may need to also include the Marina View Road extension alignment.
Significantly, a completed Spine Road would provide improved network resilience, in that it would provide an alternative route to Hobsonville Road, should either Hobsonville Road or SH18 be affected by temporary or unplanned restrictions or closures, or during an extreme traffic event.
Transport effects on the existing Hobsonville Primary School
The Hobsonville Primary School is located on the corner of Hobsonville Road and Dowdens Lane, as shown in Figure 2Error! Reference source not found.. Hobsonville Road forms a barrier to active mode trips to the school, with the school located on the north side of the road and its existing residential catchment located on the south side. Safe crossing opportunities are limited to the existing signalised intersection with Dowdens lane, and in future to any new signalised crossing locations.
Based on the residential land use predictions within surrounding areas and Whenuapai, it is anticipated that the capacity of the Hobsonville Primary School is likely to increase, resulting in more pedestrians, cyclists and cars associated with pick up/drop off activities on Hobsonville Road and Dowdens Lane near the school during the morning and afternoon school peak.
As discussed above, traffic volumes predicted around the school will be higher with the proposed Do Minimum network compared to the Spine Road network, due to the limited route choices for precinct traffic with the Do Minimum. There will therefore be a greater safety risk with regard to crashes outside
Hobsonville Corridor Precinct Technical Transportation Assessment 20 the school on Dowdens Lane and Hobsonville Road, which is of concern when considering the increased pedestrian (particularly children) activity outside the school before and after school starts and finishes.
It is noted that due to the additional capacity provided by the completed Spine Road between Hobsonville Road and the SH18 Interchange, traffic volumes on Dowdens Lane are predicted to be lower than those predicted with the network with Do Minimum network, and shorter delays will be experienced at the Hobsonville Road/Dowdens Lane intersection and Hobsonville Road/Suncrest intersection. This will reduce the delays experienced by pedestrians and vehicles in the school area and improve walk/cycling connectivity around the school area.
Connectivity Implications of Spine Road Options
Connections to the eastern side of Brigham Creek Road
The connection of the Spine Road to Brigham Creek Road is expected to be located either at the SH18 southbound off-ramp roundabout as shown in the PC14 plans (and assumed for modelled Option 1) or at the SH18 southbound on-ramp roundabout (assumed with options 2 and 3). The form of the intersection on the eastern side of Brigham Creek Road has yet to be determined; however for the purposes of the modelling, has been assumed to provide for left in and left out movements only due to the AUP (OiP) Vehicle Access Restriction Control (Motorway Interchange Control) designation on this section of Brigham Creek Road. Movements from the southern precinct areas to the northern precinct areas would be able to be accommodated by this arrangement; however, movements from the northern precinct areas to the southern areas would need to travel via Hobsonville Road.
If the form of an intersection on Brigham Creek Road providing access to the northern area of the Hobsonville Corridor Precinct also included right turns (inbound, outbound or both), it would need to be signalised due to the level of traffic using Brigham Creek Road. However, it is likely that a signalised intersection would have upstream and downstream impacts on the operation of adjacent intersections, including those at the SH18 interchange and potentially causing queuing back onto the motorway. A cross road signalised intersection that included the Spine Road connecting to Brigham Creek Road at this location would have an even greater adverse impact on the operation of Brigham Creek Road and the interchange; however, it would facilitate more direct movement between these areas of the precinct, including for pedestrians and cyclists.
Connecting the Spine Road to Brigham Creek Road at the SH18 off-ramp roundabouts
As discussed in Section 2.4 above, three options have been assessed with regard to the proposed alignment of the Spine Road and its connection to Brigham Creek Road and Hobsonville Road. The predicted traffic demands from the SATURN models at the key intersections associated with each option have been assessed in SIDRA models and the operation of the intersections has been considered, with a target of a Level of Service (LOS) D on each approach. In addition, the 95th percentile queues predicted on the SH18 off ramps have been reviewed and considered acceptable if the end of the queue does not extend to within 140 metres of the motorway off-ramp nose to reduce the risk of interference with traffic on the through lanes of the motorway. Changes will be needed at the SH18/Brigham Creek Road roundabouts to accommodate the predicted traffic volumes. Details of the assessment are included in Appendix A with a summary provided below.
Hobsonville Corridor Precinct Technical Transportation Assessment 21
Option 1: With the predicted 2021 land use and transport provisions within the area, the proposed Spine Road can be connected to the existing SH18 southbound off-ramp/Brigham Creek Road roundabout provided that the roundabout is modified to include a shared left turn/right turn lane and a right turn lane on the SH18 off-ramp approach. The roundabout would also need to be widened to include two circulating lanes on the east approach. With 2026 land uses the 2021 changes to the roundabout would need to be added to, with the southbound off-ramp needing to be widened to include a left turn slip lane, a shared through/right turn lane and a dedicated right turn lane at the roundabout. By 2026 Brigham Creek Road is anticipated to need to be widened to two lanes per direction between the intersections within the SH18 interchange, as well as the widening of the roundabouts to provide two circulating lanes between the Brigham Creek Road approaches. In addition, left turn slip lanes will also need to be provided at the Brigham Creek Road/SH18 northbound off-ramp intersection on the Brigham Creek Road west and SH18 northbound off-ramp approaches. This also requires the widening of the SH18 northbound on- ramp to include a long enough short lane to allow the left turn traffic from Brigham Creek Road west to merge with the right turn traffic from Brigham Creek Road east. Option 2: In 2021, a connection between the Spine Road and the existing SH18 northbound on- ramp/Brigham Creek Road intersection can be established with the predicted land use and transport provisions assuming that the same changes at the SH18 northbound off-ramp/Brigham Creek Road intersection as for Option 1 as well as widening of the SH18 southbound on-ramp roundabout to include two circulating lanes between Brigham Creek Road west and east, and also widening of Brigham Creek Road in the eastbound direction, between the northbound ramps and the southbound off-ramp are provided. With 2026 land uses, a left turn slip lane on the Brigham Creek Road north approach and two through lanes from Spine Road to Brigham Creek Road west approach would be needed at the SH18 Southbound on-ramp/Spine Road/Brigham Creek Road intersection. The proposed Brigham Creek Road widening to two lanes per direction on road sections and at roundabouts are also required as per Option 1. Option 3: As with Option 2, the same changes to the existing road network would need to be made. The proposed new connection between the SH18 southbound on-ramp roundabout and Hobsonville Road could initially be priority controlled at its intersection on Hobsonville Road but it would need to be signalised to accommodate the increased demands, as well as better provide for cyclists and pedestrians by 2026 depending on the nearby developments.
It should be noted that the indicative layouts provided in Appendix A and B are based on a high level assessment which relies only on the SATURN and SIDRA outputs. A more detailed assessment which includes the calibration of the base situation and further analysis of weaving/merging between intersections may be required to determine the most appropriate form and layout of the intersections.
Conclusions
Relative to the Do Minimum scenario without the Spine Road, all three connection options for the completed Spine Road are predicted to result in a number of key, strategic transportation benefits, including the following: Improved network resilience. A completed Spine Road provides an alternative main route running in parallel to Hobsonville Road. This will result in network resilience benefits when either
Hobsonville Corridor Precinct Technical Transportation Assessment 22
Hobsonville Road or SH18 are subject to temporary or unplanned closures or restrictions, or during an extreme traffic event. Improved connectivity. A connected Spine Road will provide improved connectivity within the precinct, and remove the need for all trips to use Hobsonville Road. This improved connectivity will benefit general traffic, pedestrians and cyclists, and potentially public transport users should some bus services use the Spine Road. Reduced traffic on Hobsonville Road. A completed Spine Road scenario is predicted to have significantly lower traffic volumes on Hobsonville Road than the Do Minimum, and this will lead to reduced conflict with existing vehicle crossings on the south side of this street. This in turn may provide greater redevelopment potential on the south side of this corridor, which is zoned Mixed Housing Urban within the AUP (OiP). The reduced traffic volumes on this corridor would also lead to the three following key strategic benefits. Improved opportunities for bus priority measures on Hobsonville Road. Lower general traffic on Hobsonville Road will provide greater opportunities for additional lanes on this road to be dedicated to public transport, facilitating this corridor’s proposed FTN status. The lower traffic volumes will additionally improve pedestrian accessibility to this public transport corridor, as below. Improved walking and cycling environment on Hobsonville Road. The lower traffic volumes on Hobsonville Road will in general improve the walking and cycling environment on this corridor, and reduce conflict between active mode users and traffic. The lower traffic volumes will additionally allow more opportunities for safe crossing locations of this road, better connecting the residential catchment on the south/east side of the road with employment on the north/west side, as well as connecting users to bus stops. Reduced severance to Hobsonville Primary School. Related to the walking and cycling effects above but requiring special mention, Hobsonville Primary School is severed from its existing residential catchment by Hobsonville Road, and safe crossing opportunities for school children are limited to signalised crossings. The lower traffic volumes on Hobsonville Road that a completed Spine Road provides will result in reduced conflict between pedestrians and vehicles, as well as improved opportunities for additional safe crossings.
With regard to the three different eastern connection options for the proposed Spine Road, the analysis has identified that the proposed options will result in similar effects on the road network within the Hobsonville Corridor Precinct, provided that the identified transport provisions can be provided at SH18/Brigham Creek Road.
Hobsonville Corridor Precinct Technical Transportation Assessment
APPENDIX A Predicted Traffic Volumes
Hobsonville Corridor Precinct Technical Transportation Assessment 1
Figure A1: Predicted Do Minimum Demand Flows – 2026 Morning Peak
Hobsonville Corridor Precinct Technical Transportation Assessment 2
Figure A2: Predicted Do Minimum Demand Flows – 2026 Evening Peak
Hobsonville Corridor Precinct Technical Transportation Assessment 3
Figure A3: Predicted Demand Flows – with the proposed Option 1 Spine Road Layout - 2026 Morning Peak
Hobsonville Corridor Precinct Technical Transportation Assessment 4
Figure A4: Predicted Demand Flows – with the proposed Option 1 Spine Road Layout 2026 Evening Peak
Hobsonville Corridor Precinct Technical Transportation Assessment 5
Figure A5: Predicted Demand Flows – with the proposed Option 2 Spine Road Layout - 2026 Morning Peak
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Figure A6: Predicted Demand Flows – with the proposed Option 2 Spine Road Layout 2026 Evening Peak
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Figure A7: Predicted Demand Flows – with the proposed Option 3 Spine Road Layout - 2026 Morning Peak
Hobsonville Corridor Precinct Technical Transportation Assessment 8
Figure A8: Predicted Demand Flows – with the proposed Option 3 Spine Road Layout 2026 Evening Peak
Hobsonville Corridor Precinct Technical Transportation Assessment
APPENDIX B Assessment of Spine Road Options
Hobsonville Corridor Precinct Technical Transportation Assessment 1
Modelling Assessment for Spine Road Connections to Brigham Creek Road
These assessments have relied on modelling outputs from SATURN and SIDRA models. Key performance criteria that have been included in the reporting are as follows. Volume/capacity (v/c) – this compares the predicted traffic volumes with the theoretical capacity and has been provided on an approach basis (ie not lane by lane). Desirable v/c is considered to be less than 90% 95th percentile queues – these are the queue lengths that are expected to be exceeded no more than 5% of the time. Where queues are anticipated to extend back to another key intersection, the capacity of the other intersection will be reduced Level of service – this has been based on delay for priority/signal controlled intersections and v/c for roundabouts. There are six LOS, with LOS A representing the top level as a condition where individual drivers are virtually unaffected by the presence of others in the traffic stream. LOS F represents the worst level and reflects that the movement is operating at or above its capacity
The outputs provided below are from the SIDRA models and have been used to determine what changes may be needed to intersections to accommodate expected traffic.
2021 Tests
Do Minimum Network
The predicted operational performance of the SH18/Brigham Creek Road roundabouts with the predicted traffic in 2021, with no Spine Road connection to Brigham Creek Road is summarised in the tables below. The modelled intersection layouts are provided in Appendix C of this report
Table 4: SH18 Northbound Ramps/Brigham Creek Road Intersection: 2021 Do Minimum
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) SH18 off-ramp 28 9 A 81 56 C Brigham Creek Road 27 13 A 49 29 A East Sinton Road 7 2 A 31 12 A Brigham Creek Road 58 29 A 69 40 B West Intersection 58 29 A 81 56 C
Hobsonville Corridor Precinct Technical Transportation Assessment 2
Table 5: SH18 Southbound on-ramp/Brigham Creek Road Intersection: 2021 Do Minimum
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Brigham Creek Road 56 27 A 85 84 D East Brigham Creek Road 52 0 A 73 0 C West Intersection 56 27 A 85 84 D
Table 6: SH18 Southbound off-ramp/Brigham Creek Road Intersection: 2021 Do Minimum
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Brigham Creek Road 53 33 A 79 93 C East SH18 off-ramp 31 10 A 80 69 C Brigham Creek Road 31 0 A 48 0 A West Intersection 53 33 A 81 93 C
An assessment of the modelling outputs indicates that with the predicted traffic in 2021, the three roundabouts included within the SH18/Brigham Creek Road interchange are predicted to operate satisfactorily with the existing layouts.
2021 Spine Road Option 1 connection to Brigham Creek Road
Option 1 includes the Spine Road network within the Hobsonville Corridor Precinct with the connection of the Spine Road and Brigham Creek Road being at the SH18 southbound off-ramp/Brigham Creek Road roundabout, with a separated left turn and right turn lane proposed on the Spine Road approach. The modelled intersection layout is provided in Appendix C. The predicted operational performance associated with the SH18/Brigham Creek Road Interchange intersections are provided as follows.
Table 7: SH18 Northbound Ramps/Brigham Creek Road Intersection: 2021 Option 1
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) SH18 off-ramp 32 10 A 83 61 C
Hobsonville Corridor Precinct Technical Transportation Assessment 3
Table 7: SH18 Northbound Ramps/Brigham Creek Road Intersection: 2021 Option 1
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Brigham Creek Road 28 13 A 49 29 A East Sinton Road 7 2 A 32 12 A Brigham Creek Road 63 33 A 73 45 C West Intersection 63 33 B 83 61 C
Table 8: SH18 Southbound on-ramp/Brigham Creek Road Intersection: 2021 Option 1
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Brigham Creek Road 56 28 A 85 95 D East Brigham Creek Road 59 0 A 75 0 C West Intersection 59 0 A 85 95 D
Table 9: SH18 Southbound off-ramp/Brigham Creek Road/Spine Road Intersection: 2021 Option 1
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Spine Road 26 10 A 26 23 A Brigham Creek Road 62 51 B 123 679 F East SH18 off-ramp 33 12 A 98 201 E Brigham Creek Road 37 20 A 59 41 A West Intersection 62 51 B 123 679 F
Hobsonville Corridor Precinct Technical Transportation Assessment 4
An assessment of the modelling outputs indicates that: The proposed connection between the Spine Road and the SH18 southbound off-ramp/Brigham Creek Road roundabout is predicted to increase the right turning traffic from the SH18 southbound off-ramp to Spine Road, due to the shorter route between SH18 and the Hobsonville Corridor Precinct compared to the existing Brigham Creek Road connection. Therefore, it is predicted that the new link will increase the traffic on Spine Road however the traffic on Brigham Creek Road east of SH18 interchange will be reduced LOS F is predicted on the Brigham Creek Road east approach at the SH18 southbound off- ramp/Brigham Creek Road roundabout during the evening peak. This is largely due to the increased through traffic from the SH18 southbound off-ramp to Spine Road, resulting in additional delays on the Brigham Creek Road east approach.
To reduce the predicted delays experienced at the SH18 southbound off-ramp/Brigham Creek Road intersection, the existing left and right turn lanes on the SH18 southbound off-ramp approach are proposed to be changed to a shared left turn/right turn lane and a dedicated right turn lane, with the performance of the intersection as follows.
Table 10: SH18 Southbound off-ramp/Brigham Creek Road/Spine Road Intersection: 2021 Option 1 with Shared Left Turn and Right Turn Lane
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Spine Road 23 8 A 25 9 A Brigham Creek Road 59 31 A 83 62 C East SH18 off-ramp 27 9 A 86 88 D Brigham Creek Road 37 20 A 59 36 A West Intersection 59 31 A 86 88 D
2021 Spine Road Option 2 Connection to Brigham Creek Road
It is proposed in Option 2 that Spine Road will connect to the SH18 southbound on-ramp/Brigham Creek Road intersection. Similar to Option 1 above, a two lane approach have been proposed at the Spine Road approach at the roundabout. The predicted performance of the intersections are provided in tables below, with the modelled layout of SH18 southbound on-ramp/Brigham Creek Road intersection provided in Appendix C:
Hobsonville Corridor Precinct Technical Transportation Assessment 5
Table 11: SIDRA Outputs – SH18 Northbound Ramps/Brigham Creek Road Intersection: 2021 Option 2
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) SH18 off-ramp 34 11 A 86 71 C Brigham Creek Road 29 14 A 50 30 A East Sinton Road 8 3 A 34 13 A Brigham Creek Road 66 36 B 80 56 C West Intersection 66 36 B 86 71 C
Table 12: SIDRA Outputs – SH18 Southbound on-ramp/Brigham Creek Road/Spine Road Intersection: 2021 Option 2
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Spine Road 36 16 A 48 26 A Brigham Creek Road 62 44 A 79 87 C East Brigham Creek Road 62 58 A 85 166 D West Intersection 62 58 A 85 166 D
Table 13: SIDRA Outputs – SH18 Southbound off-ramp/Brigham Creek Road Intersection: 2021 Option 2
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Brigham Creek Road 52 33 A 92 155 D East SH18 off-ramp 43 16 A 103 316 F Brigham Creek Road 28 0 A 48 0 A West Intersection 52 33 A 103 316 F
Hobsonville Corridor Precinct Technical Transportation Assessment 6
An assessment of the modelling outputs indicate that: A queue of approximately 165 meters has been predicted on the Brigham Creek Road west approach at the SH18 southbound on-ramp/Brigham Creek Road/Spine Road Intersection. This is longer that the existing distance between the SH18 southbound on-ramp/Brigham Creek Road intersection and SH18 Northbound Ramps/Brigham Creek Road intersection. This indicates that the queues on Brigham Creek Road west will extend back to the SH18/Eastbound off ramps roundabout. SIDRA modelling indicates that this queue can be reduced to 30 metres if an additional through lane to Brigham Creek Road east can be provided at the roundabout (this also requires widening of the existing roundabout to two circulating lanes between Brigham Creek West and East approach LOS F is predicted at the SH18 southbound off-ramp/Brigham Creek Road intersection, with 95th percentile queues predicted to be 315 meters on the SH18 southbound off-ramp. This is a result of the increased right turn traffic on the north approach. As such, the layout of the north approach is proposed to be changed from separated left turn and right turn lanes to a shared left turn and right turn lane plus a dedicated right turn lane (same as the widened layout proposed in Option 1). The predicted performance of the roundabout is provided in Table 12 below and it can be seen that the roundabout will operate within its capacity.
Table 14: SIDRA Outputs – SH18 Southbound off-ramp/Brigham Creek Road Intersection: 2021 Option 2 with Shared Left Turn and Right Turn Lane
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Brigham Creek Road 51 23 A 61 32 B East SH18 off-ramp 24 8 A 61 34 B Brigham Creek Road 28 0 A 48 0 A West Intersection 51 23 A 61 34 B
2021 Option 3
Option 3 proposes the same connection between the Spine Road and SH18/Brigham Creek Interchange as the above Option 2, however the new link is also proposed to be extended to intersect with Hobsonville Road near 114 Hobsonville Road. It is predicted that the layouts proposed in Option 3 will result in similar traffic flow and intersection performance as Option 2, at the SH18/Brigham Creek Road interchange intersections. Therefore, to ensure the performance of the interchange can be satisfactory, widening at the SH18 southbound on-ramp/Brigham Creek Road roundabout and at the SH18 southbound off-ramp/Brigham Creek Road roundabout will be required. These include: Widening of Brigham Creek Road in the eastbound direction to two lanes between SH18 Eastbound off-ramp and southbound off-ramp
Hobsonville Corridor Precinct Technical Transportation Assessment 7
Modify the existing layout on SH18 southbound off-ramp to include a shared left turn/through lane and a dedicated right turn lane. In addition to the above, the performance of the proposed new connection/Hobsonville Road intersection has been assessed, as a priority controlled intersection. The predicted performance of the Hobsonville Road/New Connection Intersection is provided as follows:
Table 15: SIDRA Outputs – New Spine Road Connection/Hobsonville Road Intersection: 2021 Option 3 with Priority Controlled Intersection
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Hobsonville Road West 13 0 A 13 0 A Hobsonville Road East 9 3 A 5 1 A New Connection 20 5 A 48 22 A Intersection 20 5 A 48 1 A
2026 Tests
2026 Do Minimum
The 2026 models have assumed the background traffic and the transport provisions proposed in the Scenario 2 of the Whenuapai Plan Change Stage 1 assessment. These include the removal of Sinton Road approach to the SH18/Northbound Ramps intersection and the capacity improvements at the Brigham Creek Road approaches, including the widening of Brigham Creek Road to two lanes per direction between the SH18 Northbound Ramps and the SH18 southbound off-ramp. The modelled intersection layouts are provided at the Appendix C of this technote.
Table 14 to Table 16 below provides the predicted performance of the interchange, based on the proposed layout.
Table 16: SIDRA Summary Outputs – SH18 Northbound Ramps/Brigham Creek Road Intersection: 2026 Do Minimum
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) SH18 off-ramp 50 20 A 90 98 C Brigham Creek Road 25 0 A 38 0 A East Brigham Creek Road 87 87 C 99 188 E West Intersection 87 87 C 99 188 E
Hobsonville Corridor Precinct Technical Transportation Assessment 8
Table 17: SIDRA Summary Outputs – SH18 Southbound on-ramp/Brigham Creek Road Intersection: 2026 Do Minimum
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Brigham Creek Road 74 79 C 87 143 D East Brigham Creek Road 41 0 A 53 0 A West Intersection 74 79 C 87 143 D
Table 18: SIDRA Summary Outputs – SH18 Southbound off-ramp/Brigham Creek Road Intersection: 2026 Do Minimum
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Brigham Creek Road 50 30 A 73 80 C East SH18 off-ramp 27 8 A 71 50 C Brigham Creek Road 29 0 A 50 0 A West Intersection 50 30 A 75 80 C
An assessment of the modelling outputs indicates that LOS E has been predicted at the SH18 Eastbound off ramps/Brigham Creek Road intersection, during the evening peak hour. As such, further widening has been proposed at the intersection, with additional left turn lanes proposed on the SH18 Eastbound off-ramp and the Brigham Creek Road west approach. The predicted performance of the intersection summarised in Table 17 below:
Hobsonville Corridor Precinct Technical Transportation Assessment 9
Table 19: SIDRA Summary Outputs – SH18 Northbound Ramps/Brigham Creek Road Intersection: 2026 Do Minimum with Three lanes on the Eastbound off-ramp and Brigham Creek Road West Approach
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) SH18 off-ramp 31 10 A 56 28 A Brigham Creek Road 25 0 A 38 0 A East Brigham Creek Road 44 21 A 61 29 B West Intersection 44 21 A 61 29 B
The above table indicates that the intersection will operate within its capacity with the proposed layout.
2026 Option 1
As discussed above, the intersection of the SH18 Northbound Ramps/Brigham Creek Road roundabout is predicted to operate with LOS F during the 2026 evening peak period, with the proposed 2026 land use in the Whenuapai Plan Change Stage 1. Therefore in 2026 Option 1 test, the layout with the additional left turn lanes proposed on the Brigham Creek Road and SH18 off-ramp approaches have been used, rather than the layout proposed in the Whenuapai Plan Change Stage 1 assessment. For the intersection of Brigham Creek Road/SH18 southbound on-ramp and the Brigham Creek Road/SH18 off- ramp intersections, the layouts proposed in the Whenuapai Plan Change 1 are still used.
The predicted performance of the SH18 interchange intersections are summarised in Table 18 to Table 20 below:
Table 20: SIDRA Outputs – SH18 Northbound Ramps/Brigham Creek Road Intersection: 2026 Option 1 with Three lanes on the Northbound off-ramp and Brigham Creek Road West Approach
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) SH18 off-ramp 30 10 A 56 29 A Brigham Creek Road 28 0 A 39 0 A East Brigham Creek Road 54 25 A 51 25 A West Intersection 54 25 A 56 29 A
Hobsonville Corridor Precinct Technical Transportation Assessment 10
Table 21: SIDRA Outputs – SH18 Southbound on-ramp/Brigham Creek Road Intersection: 2026 Option 1
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Brigham Creek Road 75 81 C 88 146 D East Brigham Creek Road 48 0 A 54 0 A West Intersection 75 81 C 88 146 D
Table 22: SIDRA Outputs – SH18 Southbound off-ramp/Brigham Creek Road/Spine Road Intersection: 2026 Option 1
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Spine Road 47 20 A 55 28 A Brigham Creek Road 58 32 A 82 61 C East SH18 off-ramp 35 13 A 94 148 D Brigham Creek Road 44 24 A 58 40 A West Intersection 58 32 A 94 148 D
An assessment of the modelling outputs indicates that a 95th Percentile Queue of 150 metres is predicted on the SH18 off-ramp approach at the SH18 off-ramp/Brigham Creek Road/Spine Road intersection, in the evening peak hour. Given that the distance between the motorway off-ramp nose and Brigham Creek Road is only 230 metres, the queue is considered to be too close to the motorway mainline. As such, a left turn slip lane has been proposed on the north approach of the intersection, and the predicted intersection performance is summarised in table below:
Hobsonville Corridor Precinct Technical Transportation Assessment 11
Table 23: SIDRA Outputs – SH18 Southbound off-ramp/Brigham Creek Road/Spine Road Intersection: 2026 Option 1 with A Left Turn Slip Lane on SH18 Southbound off-ramp
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Spine Road 46 20 A 53 25 A Brigham Creek Road 58 33 A 81 64 C East SH18 off-ramp 26 10 A 64 49 B Brigham Creek Road 44 24 A 59 40 A West Intersection 58 33 A 81 64 C
The above table indicates that with the proposed layout, the intersection will operate within its capacity in both morning and evening peaks, and the queues on the SH18 off-ramp are also predicted to meet NZ Transport Agency’s requirement on predicted queues.
2026 Option 2
The predicted performance of the SH18/Brigham Creek Road Interchange intersections, associated with the proposed Option 2 connection between Spine Road and SH18 southbound on-ramp intersection, is summarised in the following tables. The layouts associated with these outputs are provided in the Appendix C of this technote.
Table 24: SIDRA Outputs – SH18 Northbound Ramps/Brigham Creek Road Intersection: 2026 Option 2
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) SH18 off-ramp 31 10 A 56 29 A Brigham Creek Road 30 0 A 40 0 A East Brigham Creek Road 58 28 A 52 26 A West Intersection 58 28 A 56 29 A
Hobsonville Corridor Precinct Technical Transportation Assessment 12
Table 25: SIDRA Outputs – SH18 Southbound on-ramp/Brigham Creek Road/Spine Road Intersection: Option 2
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Spine Road 83 71 C 112 396 F Brigham Creek Road 123 909 F 122 853 F East Brigham Creek Road 60 83 A 60 50 A West Intersection 123 909 F 122 853 F
Table 26: SIDRA Outputs – SH18 Southbound off-ramp/Brigham Creek Road Intersection: Option 2
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Brigham Creek Road 46 27 A 69 75 B East SH18 off-ramp 28 9 A 70 47 C Brigham Creek Road 25 0 A 44 0 A West Intersection 46 27 A 70 75 C
An assessment of the modelling outputs indicates that LOS F has been predicted on the Spine Road and Brigham Creek Road east approach at the SH18 southbound on-ramp/Brigham Creek Road/Spine Road intersection. This is mostly attributed to the high traffic volumes on the Brigham Creek Road east approach. As such, improved capacity at the intersection has been assumed with an additional left turn slip lane proposed on the Brigham Creek Road East approach. The predicted intersection performance associated with the new layout indicates that the intersection will perform satisfactorily in both morning and evening peak periods.
Hobsonville Corridor Precinct Technical Transportation Assessment 13
Table 27: SIDRA Outputs – SH18 Southbound on-ramp/Brigham Creek Road/Spine Road Intersection: Option 2 with Additional Left Turn Lanes on the Brigham Creek Road East Approach
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Spine Road 57 31 A 74 49 C Brigham Creek Road 85 160 C 74 84 C East Brigham Creek Road 58 52 A 58 49 A West Intersection 85 160 C 74 84 C
2026 Option 3
Option 3 proposes to extend the new connection between Spine Road and SH18 southbound on-ramp to intersect with Hobsonville Road. This extension is predicted to result in minor traffic flow changes at the SH18/Brigham Creek Road Interchange intersections and therefore they have not been modelled explicitly in this option. However, the performance of the New Connection/Hobsonville Road intersection has been investigated, with its layout being both a priority controlled and signalised intersection. These are summarised in Table 26 and 27 below:
Table 28: SIDRA Outputs – New Spine Road Connection/Hobsonville Road Intersection: 2026 Option 3 with Priority Controlled Intersection Layout
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Hobsonville Road West 21 0 A 28 0 A Hobsonville Road East 21 6 A 25 8 A New Connection 45 18 B 100 165 F Intersection 45 18 N/A 100 165 N/A
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Table 29: SIDRA Outputs – New Spine Road Connection/Hobsonville Road Intersection: 2026 Option 3 with Signalised Intersection Layout
Morning Peak Evening Peak Volume/ 95th Level of Volume/ 95th Level of Capacity (%) Percentile Service Capacity (%) Percentile Service Queue (m) Queue (m) Hobsonville Road West 36 26 A 67 29 B Hobsonville Road East 63 25 B 69 33 C New Connection 61 31 B 66 63 B Intersection 63 31 B 69 63 B
Hobsonville Corridor Precinct Technical Transportation Assessment
APPENDIX C SIDRA Layouts
Hobsonville Corridor Precinct Technical Transportation Assessment 1
Table B1: 2021 Do Minimum Network – Modelled Intersection Layouts
SH18 Northbound Ramps/Brigham Creek Road SH18 Westbound on-ramp/Brigham Creek Road SH18 Eastbound off-ramp/Brigham Creek Road Base/Existing Layout
Proposed/Improved Layout As above As above As above
Comments No improvements required to achieve LOS D or better No improvements required to achieve LOS D or better No improvements required to achieve LOS D or better
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Table B2: 2021 Option 1 Indicative Layouts
SH18 Northbound Ramps/Brigham Creek Road SH18 Westbound on-ramp/Brigham Creek Road SH18 Eastbound off-ramp/Brigham Creek Road (with Spine Road) Base/Existing Layout
Proposed/Improved Layout As above As above
Comments No improvements required to achieve LOS D or better No improvements required to achieve LOS D or better Need to change the north approach to include a shared left turn/through/right turn lane and a right turn lane, however, LOS
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Table B3: 2021 Option 2 Indicative Layouts
SH18 Northbound Ramps/Brigham Creek Road SH18 Westbound on-ramp/Brigham Creek Road (with Spine SH18 Eastbound off-ramp/Brigham Creek Road Road) Base/Existing Layout
Proposed/Improved Layout As above
Comments No improvements required to achieve LOS D or better Need to include two eastbound lanes on Brigham Creek Road Need to change the north approach to include a shared left West approach to achieve LOS D or better turn/right turn lane and a right turn lane
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Table B4: 2021 Option 3 Indicative Layouts
SH18 Northbound Ramps/Brigham Creek Road Interchange New Connection/Hobsonville Road Intersection Base/Existing Layout As above Option 2
Proposed/Improved Layout As above Option 2 As above
Comments No Improvements Required No Improvements Required
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Table B5: 2026 Do Minimum Indicative Layouts
SH18 Northbound Ramps/Brigham Creek Road SH18 Westbound on-ramp/Brigham Creek Road SH18 Eastbound off-ramp/Brigham Creek Road Base/Existing Layout
Proposed/Improved Layout As above As above
Comments Need to widen Brigham Creek Road to two lanes per direction Need to widen Brigham Creek Road to two lanes per direction Need to widen Brigham Creek Road to two lanes per direction between SH18 Eastbound off-ramp and SH18 westbound off- between SH18 Eastbound off-ramp and SH18 westbound off- between SH18 Eastbound off-ramp and SH18 westbound off- ramp, as identified by Whenuapai Plan Change Stage 1 ramp, as identified by Whenuapai Plan Change Stage 1 ramp, as identified by Whenuapai Plan Change Stage 1 assessment assessment assessment Need to include additional left turn slip lanes on the Brigham Creek Road West and SH18 Eastbound off-ramp approaches to achieve LOS D at the intersection
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Table B6: 2026 Option 1 Indicative Layouts
SH18 Northbound Ramps/Brigham Creek Road SH18 Westbound on-ramp/Brigham Creek Road SH18 Eastbound off-ramp/Brigham Creek Road(with Spine Road) Base/Existing Layout
Proposed/Improved Layout As above As above
Comments No Improvements Required No Improvements Required Need to include left turn slip lane on the north approach
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Table B7: 2026 Option 2 Indicative Layouts
SH18 Northbound Ramps/Brigham Creek Road SH18 Westbound on-ramp/Brigham Creek Road (with Spine SH18 Eastbound off-ramp/Brigham Creek Road Road) Base/Existing Layout
Proposed/Improved Layout As above As above
Comments No Improvements Required Need to include left turn slip lane on the north approach, and No Improvements Required two through lanes on the Spine Road approach to Brigham Creek Road West
Hobsonville Corridor Precinct Technical Transportation Assessment 8
Table B8: 2026 Option 3 Indicative Layouts
SH18 Northbound Ramps/Brigham Creek Road Interchange New Connection/Hobsonville Road Intersection Base/Existing Layout As above Option 2
Proposed/Improved Layout As above Option 2
Comments No Improvements Required No Improvements Required