appendix b: feasibility and overshadowing assessment

Pacific Highway and Wyong Road intersection upgrade Appendix B Submissions report

Appendix B: Feasibility and overshadowing assessment

On of

Pacific Highway HW10 and Wyong Road MR335 Intersection and Approaches Upgrade

FEASIBILITY ASSESSMENT REPORT Removal of one of the two left turn lanes from Wyong Road (westbound)

Revision B

Document No. NB11462-ECC-RP-0015

May 2013

Feasibility Assessment Report

SINCLAIR KNIGHT MERZ

NB11462-ECC-RP-0015_B_Feasibility Assessment Report PAGE ii

Contents 1. Introduction 4

2. Scope of Work 5

2.1. Feasibility Assessment 5 2.2. Overshadowing Assessment 5

3. Feasibility Assessment 7

4. Overshadowing 8

4.1. Overshadowing Assessment 8 4.1.1. Option 1 – Existing without trees 8 4.1.2. Option 2 – Existing with trees 8 4.1.3. Option 3 – Current 100% Concept Design with noise wall 8 4.1.4. Option 4 – Alternate Design with noise wall 9 4.1.5. Option 5 – Alternate Design with noise wall and landscaping features 9 4.2. No.5 Yaldeeme Close Assessment 9

5. Summary 10

Appendix A Technical Note - Additional Traffic Modelling

Appendix B Swept Path Sketch

Appendix C Mark-up of 100% Concept Design Drawings

Appendix D Overshadowing Assessment Images


SINCLAIR KNIGHT MERZ NB11462-ECC-RP-0015_B_Feasibility Assessment Report iii

Document history and status Revision Date issued Reviewed by Approved by Date approved Revision type

A 17 May 2013 M. Collins R. Casimir 17 May 2013 DRAFT for RMS Review

B 27 May 2013 M. Collins R. Casimir 27 May 2013 FINAL

Distribution of copies Revision Copy no Quantity Issued to

A 1 1 RMS Project Manager

B 1 1 RMS Project Manager

Printed: 29 May 2013

Last saved: 29 May 2013 09:53 AM

File name: NB11462-ECC-RP-0015_B_Feasibility Assessment Report

Author: Michael Collins

Project manager: Robert Casimir

Name of organisation: Roads and Maritime Services (RMS)

Name of project: Pacific Highway & Wyong Road Intersection and Approaches Upgrade

Name of document: Feasibility Assessment Report

Document version: Revision B

Project number: NB11462


SINCLAIR KNIGHT MERZ NB11462-ECC-RP-0015_B_Feasibility Assessment Report 4

1. Introduction Sinclair Knight Merz (SKM) has been commissioned by Roads and Maritime Services (RMS) to undertake the Concept Design and Environmental Assessment for the Pacific Highway and Wyong Road Intersection and Approaches Upgrade (RMS Contract number: 11.2911.2603).

Following the display of the REF, RMS requested the following assessments be undertaken (refer also Variation No. 009).

Feasibility Assessment for removal of one of the left turn lanes from Wyong Road (westbound) into the Pacific Highway (referred to as the Alternate Design in this Report)

Assessment of overshadowing of existing properties in Yaldeeme Close (comparing the existing conditions with the current 100% Concept Design and with one of the left turn lanes from Wyong Road removed based on the Feasibility Assessment



2. Scope of Work 2.1. Feasibility Assessment

Undertake a brief feasibility assessment for and Alternate Design including removal of one of the left turn lanes from Wyong Road (westbound) into the Pacific Highway outlining the impacts on the position and height of retaining walls, footpaths, pedestrian underpass, drainage and existing utilities.

The scope includes the following assumptions.

Assessing the impacts on traffic not required. Updating the Cost Estimate not required. Additional noise modelling not required.

RMS later requested additional traffic modelling including removal of one left lane from Wyong Road (westbound) into the Pacific Highway under various future demand scenarios in Paramics (refer also Variation No. 010).

The Feasibility Assessment includes the following deliverables

Feasibility Assessment Report (brief report only). Hand mark-ups of the existing 100% Concept Design Drawings outlining the

impacts. Technical Note documenting the additional traffic modelling analysis including

intersection operation, level of service, average delays and queue length.

2.2. Overshadowing Assessment

Assessment of overshadowing of 7 existing properties in Yaldeeme Close (No. 1, 2, 3, 4, 5, 6 and 7). Conditions to be assessed include the following.

Existing without trees. Existing with trees. Current 100% Concept Design with noise wall. Alternate Design with one left turn lane in Wyong Road removed with noise wall. Alternate Design with one left turn lane in Wyong Road removed and landscaping

features.

The scope includes the following assumptions.

Shadow images will be depicted at 9:00AM, 12:00PM and 3:00PM on 21 June 2013.



All original files, 3D scenes, textures, materials, backgrounds, images, pug-ins etc. are not required and remain the property of SKM.

Detailed topographic survey of the existing properties (eg. buildings, floor levels, eave levels etc.) is not included in the current survey provided by RMS. If additional survey is required, it will be provided by RMS.

A noise wall height of 4m has been assumed based on Section 5.7.1 of the Noise and Vibration Assessment (NB11462-NEM-RP-0004). The noise wall will be constructed from precast panels (approx. 200mm thick). Concrete panels have been selected due to the relatively low susceptibility to vandalism and maintenance requirements.

The overshadowing assessment includes the following deliverables.

Shadow images (18 in total) for the above mentioned conditions and times in hard copy and jpg format.

Animation depicting shadowing throughout the day for each condition.



3. Feasibility Assessment The following provides an outline of the impacts the Alternate Design has on the 100% Concept Design.

The Alternate design incorporates a 3.5m width reduction in the exit taper, 2.4m width reduction through the centreline of the underpass and a 1.5m width reduction at the slip lanes (refer to Figure 1 for details).

The following impacts were identified associated with the Alternate Design.

The cantilevered section of retaining wall (RW-C refer to marked up Drawing DS2012/000155_112 in Appendix C) is no longer required as the offset from the watermain is sufficient to provide the required clear distance to the retaining wall piles. This may result in a shorter construction program due to a simpler construction method which may reduce construction costs. It may also reduce the time construction activities are directly behind 5 Yaldeeme Close so impact to access to the rear gate may be reduced (refer also sub-number 8, item 17 from the REF Submissions Report, NB11462-NEM-RW-0004).

Concrete encasement and piling of the watermain will still be required. Wyong Shire Council indicated their preference to concrete encase and pile the watermain to eliminate the requirement for future maintenance in this location.

The length of the underpass extension to the south will be reduced by approximately 2.4m (at the culvert centreline). This may improve pedestrian safety by increasing pedestrian sight distance from the south into the underpass and reduce the overall underpass length.

The overall pavement area will be reduced by approximately 280m2 (full depth AC as proposed in 100% Concept Design).

The additional traffic modelling indicates that the Wyong Road / Pacific Highway intersection is not adversely affected by the removal of one of the left turn lanes (refer Technical note in Appendix A)



4. Overshadowing The overshadowing assessment was undertaken using the Autodesk program 3DS Max.

The extent of the RMS survey used during the Concept Design is limited to the road corridor. Existing information within residential properties was required to perform an accurate assessment. Dwelling locations, floor levels, eve heights and existing vegetation heights and girth were determined by Stereo Aerial Photography, as performed by SKM. The accuracy of the survey data (+/- 300mm) was deemed suitable for the assessment.

Note that the landscaping proposed in the 100% Concept Design has not been considered in the assessment of the following options.

4.1. Overshadowing Assessment

Due to the location of the adjacent properties, the time of day where shadowing has the biggest impact on the properties of 1 to 7 Yaldeeme Close is 9:00AM. The cadastral boundary and lot numbers have been added to each of the images. As outlined in Section 2, specific images have been spliced and provided for comparison in Appendix D.

The following is a summary of the results obtained from the assessment for each scenario.

4.1.1. Option 1 – Existing without trees

This assessment highlights the impacts of shadowing if the existing trees were removed. It has been provided as a base case for the assessment.

4.1.2. Option 2 – Existing with trees

This assessment simulates the existing conditions and impacts shadowing has on the affected properties.

The images show that 5 Yaldeeme Close is under shadow for the majority of the day and that 4 and 6 Yaldeeme Close are heavily shaded in the early morning hours.

4.1.3. Option 3 – Current 100% Concept Design with noise wall

Significant shadowing can be noticed throughout the majority of the day due to the vicinity of the retaining wall and the height of the noise wall above the existing dwelling.



4.1.4. Option 4 – Alternate Design with noise wall

Although the extent of shadowing on adjacent properties is reduced compared to Option 3, there is an increase in shadowing in comparison to no noise wall for both the 100% Concept Design and the Alternate Design.

4.1.5. Option 5 – Alternate Design with noise wall and landscaping features

Significant shadowing can be noticed throughout the majority of the day due to the vicinity of the retaining wall, the height of the noise wall and the proposed vegetation.

4.2. No.5 Yaldeeme Close Assessment

Due to the significant impact the 100% Concept Design has on the existing dwelling at 5 Yaldeeme Close, additional shadow images have been developed from the perspective of the backyard.



5. Summary An Alternate Design was developed to assess the impacts of the removal of one of the two left turn lanes from Wyong Road (westbound) into the Pacific Highway as outlined in Section 3 of the Report. Impacts of the Alternate Design include a potential improvement in pedestrian safety, a reduction in construction program and simpler construction methods.

Additional traffic modelling indicates that the Wyong Road / Pacific Highway intersection is not adversely affected by the removal of one of the left turn lanes.

Assessment of overshadowing indicates that the Alternate Design does reduce the shadowing in Yaldeeme Close.



Appendix A Technical Note - Additional Traffic Modelling

Tech Note

NB11462_Tech Note_HW10 and MR335 Intersection Upgrade_1-Lane_LSB_R1.0.docx SINCLAIR KNIGHT MERZ PAGE 1

Date 13 May 2013

Project No NB11462

Revision Rev 1.0

Subject Pacific Highway HW10 and Wyong Road MR35 Intersection and Approaches Upgrade – One left turning lane into the Pacific Highway southbound

1. Introduction Sinclair Knight Merz (SKM) was previously engaged by the Roads and Maritime Services (RMS) to develop a Paramics models for the Base Case and Concept Design (CD) to upgrade the Pacific Highway and Wyong Road intersection in Tuggerah. The performance of each scenario was assessed for the 2011 base year and the 2025 and 2035 modelled years, to determine the immediate and long term impact on the performance of the network. The critical outputs from the simulation runs were extracted to assess the performance of the intersection for each scenario. The results and key findings were summarised accordingly in the report “Traffic and Transport Assessment – NB11462-ECC-RP-0004 – Rev C”, which was submitted to the Roads and Maritime Services (RMS) on the 22nd of October 2012.

Subsequent to this assessment, SKM was appointed by RMS to develop Paramics models with an option for one left turning from Wyong Road westbound into the Pacific Highway (Option: “1-left lane”). This technical note describes the impact of the proposed “1-left lane” and original CD, which consisted of two left turning lanes from Wyong Road westbound into the Pacific Highway (Option: “2-left lanes”). The performance of the intersection for the future years (2025 and 2035) under both low growth (without proposed Tuggerah Town Centre Development) and high growth scenario (including proposed Tuggerah Town Centre Development).

2. Model assumptions and stability The following assumptions have been made for the Paramics modelling:

n Demand matrices which are developed for the previous study and models (2025 and 2035, AM & PM peaks) were incorporated into this assessment.

n The light and heavy vehicles proportions for each origin/destination remain unchanged from the previous study.

n Wyong Road and Pacific Highway intersection operates as a single diamond phasing (i.e. there is no opposing right turn for traffic heading north/south along the Pacific Highway).

To ensure the robustness of the AM and PM peak models, five different seed values were run for analysing purposes. The seed values incorporated in the AM and PM peak models were 560, 28, 7771, 86524 and 2849. These five seeds are also settings defined by the RMS standards for Paramics.

Tech Note


3. Option assessment This section documents the model results for the 2025 and 2035 traffic volume scenarios for both “2-left lanes” and “1-left lane” model scenarios. Figure 1 shows the Wyong Road / Pacific Highway intersection with both the double and single slip lane configurations.

n Figure 1: Wyong Road / Pacific Highway Intersection

For the comparative assessment of proposed option, the Paramics outputs focused on the following results:

n Intersection performance

n Queue lengths

3.1 Intersection performance The RMS Guide to Traffic Generating Development specifies intersection Level of Service (LoS) as the primary criteria for the assessment of signalised intersections. The LoS determined for signalised intersections is the weighted average delay for all movements in the intersection. Generally, intersection operation of LoS C or better is considered acceptable. However in many future development situations, LoS D is considered acceptable. Intersections operating LoS E or LoS F indicate unstable operation, resulting in excessive delays and require further investigation.

It is advised that these results be assessed in conjunction with the performance from the Paramics models. The SIDRA results are only based on the extracted turning volumes from models output results. These turning volume outputs reflect the traffic that arrives at the intersection as opposed to the total demand flow. Upstream queued flow not arriving at the various intersections may be significant when the network experiences severe congestion. This impact is not considered by the SIDRA modelling.

Tech Note


The results of the analysis for intersection Pacific Highway / Wyong Road 2025 and 2035 are summarised in Table 1 and Table 2.

n Table 1: Intersection results summary – 2025 (Intersection Pacific Highway / Wyong Road )

Scenario

Low Growth Scenario High Growth Scenario

Ave Delay (seconds)

LoS

Degree of Saturation

(DoS)

Ave Delay (seconds)

LoS


(DoS) AM Peak

2-left lanes 40.7 C 0.74 40.5 C 0.67

1-left lane 41.9 C 0.85 43.4 D 0.86

PM Peak

2-left lanes 42.0 C 0.74 41.9 C 0.75 1-left lane 42.3 C 0.75 43.4 D 0.76 n Table 2: Intersection results summary – 2035

(Intersection Pacific Highway / Wyong Road )

Scenario

Low Growth Scenario High Growth Scenario

Ave Delay (seconds)

LoS


(DoS)

Ave Delay (seconds)

LoS


(DoS) AM Peak

2-left lanes 38.9 C 0.67 42.4 C 0.72

1-left lane 41.3 C 0.84 45.6 D 0.88

PM Peak

2-left lanes 43.5 D 0.78 43.7 D 0.79 1-left lane 43.5 D 0.81 43.7 D 0.81

The intersection LoS has been evaluated using SIDRA to allow for a comparison of performance between the “2-left lanes” and “1-left lane” configurations. These results are assessed in conjunction with the performance from the Paramics models. The SIDRA results for all future demand scenarios reveal the following:

2025 models:

n The “1-left lane” model performs comparably to the “2-left lanes” model for the AM period. Whilst LoS drops from C to D for the high growth scenario, the average delay is increased by less than 3 seconds, indicating only a minimal decline in performance.

n The PM peak results are very similar between both scenarios. Performance of the scenarios assessed under the low growth models is almost identical. The high growth scenario experiences an increase in average delay of less than 2 seconds and the LoS increases from LoS C to LoS D.

Tech Note


2035 Models:

n The “1-left lane” AM models experience a minimal increase in average delay of approximately 3 seconds when compared to the “2-left lanes” model scenario. Similarly to the 2025 models, the intersection LoS drops from C to D under high growth scenario.

n The “1-left lane” PM peak models perform identically to “2-left lanes” model with the average delay and LoS remaining consistent for the both the low and high growth scenarios.

The “1-left lane” and the 2-left lane” options operate similar under all future demand scenarios. Traffic volumes which perform the left turning movement from Wyong Road westbound into the Pacific Highway are relatively low and the results indicate that a single left turning lane is sufficient for future traffic demands in the Wyong area for both AM and PM peak periods.

3.2 Queue lengths An analysis of the queue lengths across all modelled scenarios reveals that there are no significant differences between the “2-left lanes” and “1-left lane” configurations.

Queuing at the Wyong Road / Pacific Highway intersection remains stable and the intersection operates consistently with a single slip lane from Wyong Road westbound into the Pacific Highway. Queuing in the relevant left turning lane is not significant in either scenario. There is unused capacity in this lane which would allow for an increase in volume without impacting on the northbound through lanes.

Figures 2 presents the queue lengths results for both slip lane configurations. The figure snapshot are extracted from 2035 AM with low growth scenario (8.00am – 8.30am) results but are indicative for all scenarios. Similar queue lengths were observed in both “2-left lanes” and “1-left lane” options.

Note: The highlight section shows the back of queue lengths from the average of five seeds Paramics results.

Tech Note


Figure 2: Back of queue length snapshots in 2035 AM with low growth (8.00am–8.30am)

Tech Note


4. Summary of the modelling assessment Paramics modelling has been undertaken in order to assess the impact of converting the two left slip lanes from Wyong Road westbound into the Pacific Highway into a single slip lane.

For the comparative assessment of proposed options, the intersection operation and queuing at the Wyong Road / Pacific Highway intersection were assessed. The assessment was completed for the AM and PM peak demands for 2025 and 2035, for low and high growth scenarios. Where a low growth was without the proposed Tuggerah development and the high growth scenario was with the proposed Tuggerah development.

The SIDRA level of service and average delay assessment for the intersection demonstrated that a single left turning lane was sufficient to accommodate the left turning traffic for 2025 and 2035 for the low and high growth scenarios.

The Paramics modelling showed that queuing at the Wyong Road / Pacific Highway intersection remains consistent for both options and therefore a second left turning lane is not required to reduce the queuing at the intersection and the queuing does not impede adjacent through lanes and cause delays or congestion for northbound traffic.

Overall, both Paramics and SIDRA modelling indicate that the Wyong Road / Pacific Highway intersection is not adversely affected by the removal of a left slip lane. The traffic volumes which perform this turning movement are relatively low and results indicate that a single slip lane will be sufficient for future traffic demands in the Wyong area for both peak periods.

Based on this assessment and comparison of traffic modelling analysis results, a single left turning lane is sufficient. The increase in intersection delay is nominal and has minimal impact on the Wyong Road / Pacific Highway intersection operation.

Prepared by: Reviewed by:

Edmund Cheung Sinead Giblin

Senior Traffic Engineer Senior Traffic Engineer



Appendix B Swept Path Sketch

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A3 original

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This sheet may be prepared using colour and may be incomplete if copied

Amendment Description Initials

ROADS AND MARITIME SERVICES

REGISTRATION NUMBER

VOLUME No.FILE No.

SHEET No.

ISSUE

Co-ordinate System: MGA Zone 56 Height Datum: A.H.D.

Prepared By

ACN 001 024 095

Tel: (02) 9928 2100 Fax (02) 9928 2500

St Leonards NSW 2065 Australia

Sinclair Knight Merz Pty Ltd

100 Christie Street

PROJECT No NB11462

DATE

: 15/0

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NB11462-ECC-SK-0029 0001

NOT FOR CONSTRUCTION

PACIFIC HIGHWAY HW10 AND WYONG ROAD MR335, TUGGERAH

SHIRE OF WYONG

INTERSECTION AND APPROACHES UPGRADE

SWEPT PATHS - ALTERNATE DESIGN

SHEET 1

A 80% ISSUE ALM 16.05.13

B

TRACK 2: ST 30km/hSWEPT PATHS NOTES



Appendix C Mark-up of 100% Concept Design Drawings

appendix b: feasibility and overshadowing assessment

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