old wallgrove road widening · 2019-10-03 · with the m4 motorway (at a new interchange) and the...

Old Wallgrove Road Widening (Roberts Road to Wallgrove Road) Eastern Creek

Submissions Report APRIL 2013

RMS 13.253 ISBN 978-1-922245-30-4

(blank page)

Prepared by

Aurecon Australia Pty Ltd ABN 54 005 139 873 116 Military Road (PO Box 538) Neutral Bay New South Wales 2089 Australia T: +61 2 9465 5599 F: +61 2 9465 5598 E: [email protected] W: aurecongroup.com Provide Roads and Maritime Services Publication Number

Roads and Maritime Services

Old Wallgrove Road Widening

(Roberts Road – Wallgrove Road)

Eastern Creek Submissions report 2 April 2013

Old Wallgrove Road Widening (Roberts Road – Wallgrove road), Eastern Creek Review of environmental factors i Submissions Report

Executive summary

Roads and Maritime Services of NSW (RMS) proposes to widen Old Wallgrove Road between the intersection of Roberts Road and Wallgrove Road. Old Wallgrove Road requires upgrading to accommodate future traffic growth in the Western Sydney Employment Area (WSEA). The proposal consists of the following features: The upgrade of Old Wallgrove Road to four lanes between Roberts Road and

Southridge Street and six lanes between Southridge Street and Wallgrove Road within a 40 metre wide road corridor.

Provision of a wide median between Roberts Road and Southridge Street to facilitate the future widening of Old Wallgrove Road to six lanes to accommodate future traffic generated by the WSEA.

The upgrade of four intersections with local roads (Roberts Road, Eastern Creek Drive, Southridge Street and Quarry Road) to signalised intersections.

The construction of a new mini-link road between Wallgrove Road (opposite the M7 northbound on/off ramps) and Old Wallgrove Road (opposite Quarry Road) including the connection of mini-link road with Capicure Drive.

The upgrade of a short length of Old Wallgrove Road west of the intersection with Roberts Road to tie in with the Erskine Park Link Road project.

The widening of the Reedy Creek Bridge and the duplication of the Eskdale Creek Bridge.

The widening of Wallgrove Road between Old Wallgrove Road and the mini-link road including tie in works to the north of Wallgrove Road intersection with Old Wallgrove Road and south of Wallgrove Road intersection with the mini link road.

A review of environmental factors (REF) was prepared for the proposal and placed on public display from 23 October 2012 to 23 November 2012. The REF was on display on the RMS website at www.rms.nsw.gov.au and at the following locations: St Clair Library. Mount Druitt Library. Mount Druitt Motor Registry. Blacktown Motor Registry. St Marys Motor Registry. Wetherill Park Motor Registry. A total of six submissions were received, one from Blacktown City Council and five from stakeholders. None of the submissions objected to the proposal, however, the following issues were raised by respondents: Traffic and access impacts. Water quality and hydrology impacts. Land use and property impacts. Noise impacts. Stakeholder and community consultation. In response to issues raised in submissions, additional investigations were undertaken to further assess traffic and access requirements as well as flooding and drainage impacts. The findings of these investigations are summarised below.

Old Wallgrove Road Widening (Roberts Road – Wallgrove road), Eastern Creek Review of environmental factors ii Submissions Report

Traffic and access Based on the additional traffic impact assessment (GHD February 2013), it has been concluded that the concept design undertaken as part of the REF has sufficient mid block capacity to serve the traffic demand for the year 2021 (design year) even under a higher trip generation rate adopted for the Ropes Creek Precinct as requested by Blacktown City Council. Furthermore, the supplementary traffic assessment concluded that no works other than line marking on the Motorway ramps as detailed in the concept design would be required within the M7 Motorway corridor, at least up to the design year. However, in order for all intersections as part of the proposal to function at a level of service of at least D, it has been concluded that Archbold Road has to be extended by 2021 from Erskine Park Link Road to the Great Western Highway with east facing ramps at the M4 Motorway. This proposed extension of Archbold Road is part of a Part 3A concept approval for the Western Sydney Employment Hub Erskine Park Link Road Network concept plan environmental assessment (WSEA concept plan). This concept plan includes progressive provision of a number of local arterial roads including: An east-west route as an extension of Lenore Lane, connecting Mamre Road and

Erskine Park Road with the interchange at Wallgrove Road and the M7 Motorway (including this proposal).

Eastern and western north-south link roads connecting the Erskine Park Link Road to the south-west precinct of the WSEA.

A northern access road to Archbold Road connecting Erskine Park Link Road with the M4 Motorway (at a new interchange) and the Great Western Highway.

Drainage and flooding The additional drainage and flooding assessment (Lyall and Associates February 2013), showed that a temporary sedimentation basin proposed at a location east of the intersection of Old Wallgrove Road and Eastern Creek Drive was not required as part of the proposal. In its place, more localised control measures would be designed as part of detailed design. The additional assessment also re-assessed the flood modelling of Eskdale Creek. The re-assessment confirmed that peak 100 year average recurrence interval (ARI) flow in the creek would not be increased by the proposal.

Old Wallgrove Road Widening (Roberts Road – Wallgrove road), Eastern Creek Review of environmental factors iii Submissions Report

Contents

Executive summary ........................................................................................... i

1 Introduction and background ...................................................................... 1

1.1 Purpose ........................................................................................................ 1

1.2 The proposal ................................................................................................ 1

1.3 REF display .................................................................................................. 2

2 Response to issues .................................................................................... 3

2.1 Overview of issues raised ............................................................................ 3

2.2 Traffic and access ........................................................................................ 4

2.3 Flooding and drainage ................................................................................ 11

2.4 Noise and vibration ..................................................................................... 15

2.5 Property acquisition .................................................................................... 16

2.6 Planning for future work within the M7 Motorway ....................................... 17

2.7 Staging of works ......................................................................................... 18

2.8 Stakeholder and community consultation ................................................... 18

3 Additional assessment .............................................................................. 21

3.1 Additional traffic and access assessment .................................................. 21

3.2 Additional flooding and drainage assessment ............................................ 22

4 Environmental management ..................................................................... 24

4.1 Environmental management plans (or system) .......................................... 24

4.2 Summary of safeguards and management measures ............................... 24

4.3 Licensing and approvals ............................................................................. 42

5 References ............................................................................................... 43

Appendix A .................................................................................................... 44

Appendix B .................................................................................................... 46

Appendix C .................................................................................................... 48

Index of Figures

Figure 1: Concept Plan ............................................................................................. 20

Old Wallgrove Road Widening (Roberts Road – Wallgrove Road), Eastern Creek Submissions report 1

1 Introduction and background

1.1 Purpose This submissions report relates to the review of environmental factors (REF) prepared for the Old Wallgrove Road Widening (Roberts Road – Wallgrove Road), Eastern Creek, and should be read in conjunction with that document. The REF was placed on public display and submissions relating to the proposal were received by Roads and Maritime Services (RMS). This submissions report summarises the issues raised and provides responses to each issue (Chapter 2). It also details investigations carried out since finalisation of the review of environmental factors (Chapter 3) and identifies any new or revised environmental management measures (Chapter 4).

1.2 The proposal RMS proposes to widen Old Wallgrove Road between the intersection of Roberts Road and Wallgrove Road, Eastern Creek (the proposal). The proposal also includes a new mini-link road between Old Wallgrove Road and the M7 northbound on/off ramps and localised widening of Wallgrove Road. The proposal is required to accommodate future traffic growth in the Western Sydney Employment Area (WSEA). The proposal aims to cater for the staged release of employment lands in the WSEA. Currently, Old Wallgrove Road is a two-lane, two-way road (one lane in each direction) with little to no shoulders and no kerbs. The proposal is to widen Old Wallgrove Road to four lanes (two lanes in each direction) between Roberts Road and Southridge Street and to six lanes (three lanes in each direction) from Southridge Street to Wallgrove Road, within a 40 metre wide road corridor. A wide median would be provided between Roberts Road and Southridge Street to facilitate the potential future upgrade of this section of Old Wallgrove Road to six lanes to accommodate future traffic generated by the WSEA. The proposal consists of four intersection upgrades including works on side streets at Roberts Road, Eastern Creek Drive, Southridge Street and Quarry Road. A mini-link road is also proposed between Wallgrove Road (opposite the northbound M7 on/off ramps) and Old Wallgrove Road (opposite Quarry Road), including a left-in/left-out intersection with Capicure Drive. The proposal also includes localised widening of Wallgrove Road including widening of the bridge over Reedy Creek and duplication of the bridge over Eskdale Creek. Old Wallgrove Road is located on land at Eastern Creek off Wallgrove Road and has gently sloping topography. Wallgrove Road crosses Reedy Creek (south of Old Wallgrove Road) and Eskdale Creek (north of Old Wallgrove Road). Old Wallgrove Road provides an east-west link, while Wallgrove Road provides a north-south link at this location. Land within the proposal area has been previously cleared and is currently being developed as industrial and employment generating precincts. Remnant vegetation occurs along Old Wallgrove Road between Roberts Road and Southridge Street, generally along its southern boundary. Other adjacent lands are either developed or cleared of vegetation.


The proposal consists of the following features: The widening of Old Wallgrove Road to four lanes between Roberts Road and

Southridge Street and six lanes between Southridge Street and Wallgrove Road within a 40 metre wide road corridor.

Provision of a wide median between Roberts Road and Southridge Street to facilitate the future widening of Old Wallgrove Road to six lanes to accommodate future traffic generated by the WSEA.

The upgrade of four intersections with local roads (Roberts Road, Eastern Creek Drive, Southridge Street and Quarry Road) to signalised intersections.

The construction of a new mini-link road between Wallgrove Road (opposite the M7 northbound on/off ramps) and Old Wallgrove Road (opposite Quarry Road) including the connection of mini-link road with Capicure Drive.

The upgrade of a short length of Old Wallgrove Road west of the intersection with Roberts Road to tie in with the Erskine Park Link Road project.

The widening of the Reedy Creek Bridge and the duplication of the Eskdale Creek Bridge.

The widening of Wallgrove Road between Old Wallgrove Road and the mini-link road including tie in works to the north of Wallgrove Road intersection with Old Wallgrove Road and south of Wallgrove Road intersection with the mini-link road.

1.3 REF display RMS prepared a review of environmental factors to assess the environmental impacts of the proposal. The review of environmental factors was displayed from 23 October to 23 November 2012 at six locations, as detailed in Table 1.1. The review of environmental factors was placed on the RMS website and made available for download. Table 1.1: Display locations

Location Address

St Clair Library Shop 12, St Clair Shopping Centre, Bennett Road and Endeavour Avenue

Mount Druitt Library The Mount Druitt Hub, Ayres Grove Mount Druitt Motor Registry

23-27 Luxford Road, Mount Druitt

Blacktown Motor Registry

Shops B1/B2 Blacktown Mega Centre, Cnr of Blacktown Road and St Martins Crescent

St Marys Motor Registry Shop M04, Station Plaza 33-43 Phillip Street, St Marys

Wetherill Park Motor Registry

Unit 72, Greenway Plaza Cnr of The Horsley Drive and Elizabeth Street Wetherill Park

In addition to the above public exhibition, an invitation to comment and copy of the review of environmental factors was sent directly to several identified stakeholders, including adjacent land owners, Blacktown City Council and the Department of Planning and Infrastructure (Appendix A).


2 Response to issues

Roads and Maritime Services received six submissions, accepted up until 23 November 2012. Table 2.1 lists the respondents and each respondent’s allocated submission number. The table also indicates where the issues from each submission have been addressed in this report. Table 2.1: Respondents

Respondent Submission No.

Section number where issues are addressed

WSO Co Pty Ltd (Westlink M7)

1 2.2.3, 2.3.3, 2.4, 2.5, 2.6, 2.8

Blacktown City Council

2 2.2.1, 2.2.4, 2.3.2, 2.5, 2.7

Jacfin Pty Ltd (business)

3 2.2.2, 2.3.1, 2.5

The Austral Brick Company Pty Ltd (business)

4 Letter of support for the proposal. No response required

Individual 5 2.2.4 Individual 6 2.2.4

2.1 Overview of issues raised A total of six submissions were received in response to the exhibition of the REF comprising one response from local council and five from stakeholders. Each submission has been examined individually to understand the issues being raised. The issues raised in each submission have been extracted and collated, and corresponding responses to the issues have been provided. Where similar issues have been raised in different submissions, only one response has been provided. The issues raised and Roads and Maritime Services’ response to these issues forms the basis of this chapter. None of the submissions received objected to the proposal. The main issues raised by Blacktown City Council included: Traffic and access Drainage and flooding Property acquisition Staging of construction Stakeholder and community consultation. Issues raised by stakeholders (including local businesses) primarily related to the following: Traffic and access Drainage and flooding Noise impacts Impact on adjoining road network due to changes in land use Property acquisition


Stakeholder and community consultation.

2.2 Traffic and access

2.2.1 Land use assumptions and trip generation

Submission numbers

2

Issue description

1. In the REF, the section of Old Wallgrove Road between Roberts Road and Southridge Street is shown as widening to four lanes based on developable land assumptions for various precincts within the WSEA. Council experience is that the rate of development in Eastern Creek precinct is much higher than anticipated in the precinct planning. It is expected that the Eastern Creek precinct will be fully developed well before 2021.

2. There is an inconsistency in the trip generation rate used in the traffic study for the proposal for Ropes Creek precinct and Erskine Park Employment Area. 10 trips per hectare for a two hour peak period were used for both precincts whereas 21 trips per hectare were used for the rest of the WSEA.

3. Council is concerned that the inconsistency has affected the results, which show reduced traffic volumes in the network (by up to 50%). It appears that the use of a reduced trip generation is an attempt to justify a four lane configuration for the section of Old Wallgrove Road between Roberts Road and Southridge Street.

4. It is unclear whether the intersections would perform at a satisfactory level of service if 21 trips per hectare for a two hour peak period were adopted for the entire WSEA.

5. Council is concerned that RMS would adopt an alternate trip generation rate to the one used for other development assessments.

Response

As identified in section 2.1 of the REF, this proposal is part of the Western Sydney Employment Hub Erskine Park Link Road Network concept plan environmental assessment (WSEA concept plan, refer to Figure 1). This concept plan was approved in August 2009 by the Minister for Planning under (former) Part 3A of the Environmental Planning and Assessment Act 1979. This concept plan provided for the future development of the Western Sydney Employment Area (WSEA). The assumptions on the adjacent development used for the traffic assessment in the REF and the design of the proposal are consistent with those identified in this concept plan. A summary of the land use assumptions and rate of development adopted in the REF for 2021 (design year of the proposal) for various precincts with the WSEA is as follows:

100% of the Eastern Creek precinct and Erskine Park Employment Area. 67% of the Ropes Creek Precinct. 53% of the lands south of the Sydney Water Pipelines.

As these assumptions are consistent with the approved concept plan, these are considered adequate for the development of the proposal at this stage.


However , the proposal has provided for the future upgrade of the road to six lanes between Roberts Road and Southridge Street when traffic demands it. The development of this upgrade could be further considered if adjacent development is at an accelerated rate compared to the rate adopted for the proposal. Section 6.1 and Appendix F of the REF identify the traffic assessment and potential impacts of the proposal. The trip generation rates adopted for the proposal were consistent with the trip rates adopted for the Part 3A WSEA concept plan approval, which were generally consistent with the information provided by respective local councils. These trip generation rates generally provided for 10 trips generated per hectare of development within Penrith council local government area and 21 trips generated per hectare of development within Blacktown council local government area over a two hour period. However, the concept plan adopted only 10 trips generated per hectare over a two hour period for the Ropes Creek precinct being at the edge of both council areas and this assumption was adopted for traffic assessment for the proposal. Following Blacktown council submission a sensitivity analysis has been carried out using 21 trips per hectare of development for the Ropes Creek precinct to test the adequacy of the proposed road corridor and the level of service predicted for each of the intersections within the proposal. This further assessment is outlined in section 3 of this report and a full copy of the assessment can be found in Appendix B. This traffic assessment found that the increase in the trip generation rate for the Ropes Creek precinct to 21 trips per hectare resulted in an additional 1000 trips per hour in the 2-hour peak periods. The additional assessment confirmed that provided Archbold Road, being the nearest road to the Ropes Creek precinct, is extended from Erskine Park Link Road to the Great Western Highway with east facing ramps at the M4 Motorway is completed by 2021 (proposal design year), that: The Old Wallgrove Road upgrade proposal has sufficient mid block capacity to

serve the increased traffic demand associated with a higher trip generation rate for Ropes Creek precinct for the 2021 design year.

The performance of the intersections meets the proposal criteria of at least a level of service (LoS) of D for all intersections within the proposal.

2.2.2 Access to northern precincts off Old Wallgrove Road

Submission numbers

3

Issue description

1. The SEPP 59 Concept Masterplan road pattern has changed because of recent subdivision approvals for the creation of new internal roads. This needs to be taken into account for the proposal.

2. To facilitate future employment land development in the area there would be a benefit from another access road to the north from Old Wallgrove Road/Erskine Park Link Road between Eastern Creek Drive and the Archbold Road extension off Erskine Park Link Road. This would provide a northern leg to service the remaining 100ha of employment lands.

3. The traffic modelling demonstrates that a revised Old Wallgrove Road/Roberts Road intersection providing a 4-way intersection is appropriate and would be


suitable for truck turning movements.

4. The 4th leg would provide more permeability through the employment land and provide an alternate access to Old Wallgrove Road other than Eastern Creek Drive.

5. Developments on the southern side of Old Wallgrove Road have benefitted from access via signalised intersections to facilitate development to the north of Old Wallgrove Road. The signalised intersection of Old Wallgrove Road / Roberts Road should have provision for a 4th leg to serve the land to the north in order to provide reasonable access and provide for all turning movements for future development of the employment land.

6. RMS is requested to include provision for potential access to the private development Lot 11 at the new Old Wallgrove Road/Roberts Road intersection with a 4th leg northern approach.

Response

As identified above in section 2.2.1, the proposal is consistent on the concept plan approval for the Western Sydney Employment Hub Erskine Park Link Road Network concept plan environmental assessment (WSEA concept plan). This plan nominated the main arterial roads for the development and limited the number of local road connections with these arterial roads. Limiting the number of direct accesses onto arterial roads to formalised intersections would assist with future traffic management and traffic flow through the precincts. Any changes to the road pattern in the SEPP 59 Masterplan as identified in the submission would only affect the internal roads that serve the individual precincts. These changes would not affect the location and style of the intersections identified as part of the Old Wallgrove Road upgrade proposal. The traffic analysis considered the traffic generated for each precinct and how this traffic would interact with the proposed signalised intersections. The WSEA concept design and precinct planning developed by Blacktown City Council only provided for the number of intersections that are provided in the proposal outlined in the REF. In addition, the traffic analysis for the proposal outlined in section 6.1 and Appendix F of the REF did not identify that there is a need for an additional intersection to the northern side of the WSEA between (the future) Archbold Road and Eastern Creek Drive. The proposed intersections at Eastern Creek Drive, Southridge Street and Quarry Road would provide sufficient connections for the adjacent precinct developments. Therefore, it is not proposed to include an additional intersection connecting the northern side of the WSEA to Old Wallgrove Road, or to provide a fourth leg at the Roberts Road intersection. Three access locations are provided from Old Wallgrove Road for both the northern and southern side of the WSEA. However, the Roberts Road intersection has been designed in a way that it could accommodate a future upgrade to a four way intersection, if required. Blacktown City Council and the Department of Planning and Infrastructure are responsible for managing any changes to the precinct plan. All intersections have been designed to accommodate all vehicle movements including b-double trucks.


2.2.3 M7 Motorway access

Submission numbers

1

Issue description

1. Whilst the GHD Traffic and Transport Report contains modelling of the M7-off ramp impacts, no detailed modelling has been provided as to the performance of the on-ramps and how any on-ramp deficiencies might be addressed (e.g. lane widening, ramp metering). There does not appear to have been any detailed consideration given to the immediate impact of the widening of Wallgrove Road will have on the M7 Motorway and the interface issues that will arise in relation to such works. What interface arrangements are proposed by RMS to address these risks?

2. WSO Co’s review of the EMME modelling (as summarised in the GHD Traffic and Transport report) suggests that road capacity constraints are already being reached both northbound and southbound on the M7 between M4 and Old Wallgrove Road. The Paramics modelling also suggests deficiencies at the M7 northbound on and off ramps at Wallgrove Road in the future, with the 2021 model suggesting that flows onto the M7 from Wallgrove Road may reach their capacity in 2021; which will result in queues on the M7 northbound ramps.

3. The GHD Traffic and Transport Report does not consider in detail the impact that the creation of merge conflicts or the potential compromising of safety resulting from the changed “traffic flows and routes” will have. No consideration has been given to long term impacts on the M7 Motorway such as congestion, loss of traffic on the M7 Motorway and the instances of trip reductions due to the Wallgrove Road Upgrade and how these impacts will be mitigated.

4. It is noted that there is a modelling error in the report. The 2021 Wallgrove Road/mini-link road/M7 model shows that the M7 ramp incorrectly operating at “Level of Service A” even though it’s constituent movements operate at Levels of Service C, D and F. The SIDRA model summary shows a “NaN” error code which is considered very serious by SIDRA Solutions who have commented that they “would be very hesitant to make use of these results without establishing the cause of this problem”.

5. No consideration has been given to long term impacts on the M7 Motorway and the instances of trip reductions due to Wallgrove Road upgrade and how these impacts will be mitigated.

6. Request that RMS continues to consult with WSO on future projects in the local area and any plans to resolve any potential future capacity constraints on the M7 Motorway.

Response

Section 6.1 and Appendix F of the REF identify the traffic assessment and potential impacts of the proposal, this includes consideration of the M7 on and off ramps within the proposal area. The traffic modelling undertaken by GHD has taken into consideration the interface of the M7 on and off ramps at Wallgrove Road at the micro simulation stage. The initial modelling did identify that some widening of the northbound on-ramp along with localised widening of the M7 Motorway between the


M4 Motorway and Old Wallgrove Road would be required by 2031. In response to a number of submissions raised, some further traffic analysis (sensitivity analysis) was undertaken for the proposal as outlined above in 2.2.1. This additional traffic modelling that includes additional trip generation from the Ropes Creek precinct from 10 to 21/trips/hectare/2hrs and the inclusion of the Archbold Road east-facing ramps with the M4 Motorway has shown that no additional widening works within the M7 Motorway are required for the Old Wallgrove Road proposal. The revised traffic modelling with the Archbold Road east facing ramps at the M4 Motorway shows that there is unlikely to be queuing from Wallgrove Road onto the M7 Motorway in the peak periods for the 2021 design year. Further modelling of the 2031 future horizon year shows that the following localised improvements would be required between 2021 and 2026:

Construction of the Southern Link Road.

Widening of the M7 southbound lanes to four lanes between the M4 Motorway and Old Wallgrove Road.

Widening of the existing southbound off-ramp to Old Wallgrove Road to two lanes.

The traffic modelling also identified that the intersection of Old Wallgrove Road and Wallgrove Road is likely to be reaching capacity in the morning peak period by 2026 and that queues from this intersection are likely to extend back to the M7 Motorway.

The micro simulation modelling has taken into account the impacts of merging on traffic flows on the M7 in the immediate local area of Old Wallgrove Road. The micro simulation modelling has identified that there are unlikely to be substantial impacts on the capacity of the M7 Motorway between the M4 Motorway and Old Wallgrove Road as a result of the proposal for the 2021 design year traffic demand. Merge impacts are expected by 2026, particularly in the southbound direction in the morning peak period, where the traffic from the M4 Motorway to the M7 Motorway is likely to conflict with traffic leaving the M7 to join Old Wallgrove Road. Widening of this section and the off-ramp to Old Wallgrove Road will mitigate this. However, queuing onto the M7 Motorway is still likely as this widening will not increase the capacity of the Old Wallgrove Road and Wallgrove Road intersection, which is likely to be over capacity by 2031.

These works are outside the scope of this proposal, however this modelling could provide background information for any future proposals to undertake such works to improve the local network.

Section 3 of the REF identifies the description of the proposal including all works to occur on Wallgrove Road. This includes the widening of Wallgrove Road between Old Wallgrove Road and the mini-link road (including tie-in works) and widening of Reedy Creek Bridge and the duplication of the bridge over Eskdale Creek. The proposed widening of Wallgrove Road is only required to provide sufficient space for the upgraded intersection at Wallgrove Road/Old Wallgrove Road/M7 ramp and the new intersection at Wallgrove Road/mini-link road/M7 ramp. It is also intended to respond to the increased need for accessibility to the Western Sydney Employment Area and not as a cross-regional route or to provide an alternative to the M7 Motorway. Based on the traffic analysis there are unlikely to be any immediate impacts of the proposed widening of Wallgrove Road on the operation of the M7 Motorway. Localised widening of Wallgrove Road is unlikely to make Wallgrove Road


comparable in speed or congestion to the M7 and it is very unlikely that traffic will divert from the M7 Motorway to use Wallgrove Road for any substantial distance. Analysis of strategic model traffic volumes shows that further development within the WSEA will result in more traffic using the M7 Motorway, especially during peak periods.

The traffic modelling undertaken for the REF and subsequent modelling for the submissions report does not identify that the proposed changes to the line marking within the M7 would have any impacts to the current or future functioning of the M7 Motorway. The future impact on the operations of the M7 Motorway as a result of further development within the WSEA (and increased traffic on Old Wallgrove Road beyond the design year of 2012) would be assessed as part of future proposals. There would be on-going discussions and negotiations with the WSO Co as the employment hub develops further and local road network demands change to assist in the planning of future upgrade to the M7 motorway.

Further review has been undertaken in response to the submission identifying the modelling error for the M7 ramp Level of Service (LoS) outlined in Appendix F of the REF. It was identified that the “NaN error code” and resulting Level of Service measurement for the M7 ramp identified are a display error relating to an older version of the software. Revised model outputs provided by SIDRA Solutions showed that the model outputs produced by the newer software version are consistent with those provided in the REF (Appendix F) report. These revised SIDRA results are provided in Appendix B of this report.

2.2.4 Other access related issues

Submission numbers

2, 5, 6

Issue description

1. Whether Erskine Park Road would become a light limit load once the proposal is complete.

2. There is lack of public transport for access to childcare and the industrial area.

3. Requests that appropriate controls be implemented to ensure traffic movement is not significantly impacted during construction.

4. Requests that safety barriers be installed along Wallgrove Road adjacent to the Westlink M7 offices.

Response

Erskine Park Road is located about five kilometres west of the proposal area and therefore outside the scope of this proposal. The upgrade of Old Wallgrove Road and the provision of the Erskine Park Link Road (which is currently under construction by RMS) would provide a thoroughfare between Erskine Park Road (via Lenore Drive) and Wallgrove Road and/or the M7 Motorway. Therefore, there may be an incentive for heavy vehicles to utilise the new link to access these main arterial roads or the development within the WSEA. Erskine Park Road is a state road under the management of RMS. At this stage RMS does not propose to change the classification of Erskine Park Road as a result of the new link. Therefore,


the road could continue to be used by heavy vehicles. As identified in section 3.1 of the REF, the proposal has included the provision of:

Bus priority measures at each intersection along Old Wallgrove Road (excluding the intersection at Wallgrove Road). These would consist of bus stops (with no indentation) and bus ‘jump start’ facilities on the departure side of each intersection. The bus stops would consist of a sign and an area for passengers to alight and disembark. No bus shelters would be provided.

A three metre wide shared pathway is proposed (pedestrian and cyclist) along the northern side of Old Wallgrove Road for the length of the proposal. Connection to the shared pedestrian path being established as part of the Erskine Park Link Road project (currently under construction) and to the M7 Motorway shared pathway (via Wallgrove Road) would also be provided.

Provision of these facilities as part of the proposal provides an opportunity to introduce a reliable and frequent bus service that could serve the WSEA and provide improved public transport to this area.

Section 6.1.3 of the REF identifies a safeguard to minimise the potential impacts of construction on existing traffic movements. This safeguard identifies that prior to construction, a traffic management plan would be prepared to identify traffic management measures during construction. These measures would describe how:

Traffic control would be provided to manage and regulate traffic movements during construction.

To notify road users about traffic changes/disruptions.

To consult with property owners on property access disruptions.

Disruption to all road users during construction would be kept to a minimum.

Construction and delivery vehicles entering or leaving the site compound and/or stockpile sites would use designated haulage routes identified in the plan for traffic control. These movements would be restricted to non-peak periods as specified in the plan to minimise movements on adjacent roads during construction.

In addition, the following safeguards would be added to the safeguards identified for the proposal to further consider the potential impacts of construction on existing traffic movements:

Consideration would be given to the staging of construction to minimise impacts to existing traffic flow. This would include but not be limited to the construction of the mini-link road as early works to allow it to open to traffic while other areas of the upgrade are constructed.

The functioning of intersections during construction would be monitored and signalisation of these intersections changed as required to ensure efficient traffic movement, particularly during peak hours.

Currently there are no safety barriers established on Wallgrove Road surrounding the Westlink M7 offices and the proposal is unlikely to alter the traffic regime along Wallgrove Road in the vicinity of Westlink M7 offices. However, as part of detailed design for the proposal further road safety audits would be undertaken and mitigation measures would be put in place to address any safety concerns that the audit may highlight.


2.3 Flooding and drainage

2.3.1 Construction water quality and hydrology Submission numbers

3

Issue description

1. The proposed drainage strategy and temporary sediment basin shown on Figure 3-7a has a severe impact on the development potential of Lot 11, particularly at the corner of Eastern Creek Drive. Jacfin strongly objects to the location of the temporary sediment basin and find this an unacceptable treatment for this prominent corner location for employment land.

2. There is a better solution to the drainage treatment which would reduce the impacts on the development potential of the Jacfin land. As part of the industrial subdivision, a temporary detention basin has been constructed near the bend in Eastern Creek Drive prior to discharging into Eskdale Creek. The suggested approach is that RMS should drain Old Wallgrove Road via a permanent pipe system to this current temporary detention facility which would remove the need for the proposed temporary sediment basin at the intersection.

Response

Section 3 and Figure 3-7a of the REF identifies that as part of the preliminary concept design for erosion and sediment control management, a temporary sediment basin could be constructed at the north-eastern corner of the Old Wallgrove Road/Eastern Creek Road intersection. These erosion and sediment controls are preliminary for the concept design and would be refined during detailed design. However, as a result of the submission, RMS commissioned an additional hydrology assessment to determine if there was an alternative to creating a temporary sediment basin in this location. The full details of this additional assessment are outlined in section 3 of this report, and the findings are summarised below. Based on the findings of the review, it has been determined that the proposed temporary sediment retention basin shown at the north-eastern corner of the Old Wallgrove Road/Eastern Creek Drive intersection can be omitted from the erosion and sediment control plans. Alternatively, more localised erosion and sediment control measures, in accordance with Blue Book (volume 2D), could be applied to this catchment to control erosion and sediment during construction. Consequently, it is unlikely that the proposal would need to use the industrial subdivision’s temporary detention basin near the bend in Eastern Creek Drive as outlined in the submission. However, this option would be further considered during detailed design if required. The safeguards outlined in section 6.6.3 of the REF identify that an erosion and sediment control plan would be developed in accordance with the Managing Urban Stormwater Soils and Construction, Volume 2D, Main Road Construction (DECC 2008). This plan would be developed by the construction contractor prior to construction and would utilise the staging plan for construction. This plan would include localised measures to control erosion and sediment for the catchment that previously would have drained to the location proposed in the REF.


2.3.2 Council basins

Submission numbers

2

Issue description

1. The stormwater management strategy proposed relies almost entirely on utilising existing or proposed stormwater detention and water quality treatment basins. This approach is acceptable on the basis that suitable financial contributions are made to the cost of council basins commensurate with the area draining relative to the total catchment size.

2. There are three council regional basins serving the Eastern Creek precinct Stage 3 that the Old Wallgrove Road upgrade will drain into. A detailed assessment of the impact on these basins is required as part of the detailed design for approval by Council. The assessment will need to include all stormwater, hydrologic, hydraulic and water quality modelling data files for review by Council.

3. The proposed upgrade of Old Wallgrove Road and Wallgrove Road shall not adversely impact the operation of existing basins. Also any afflux or adverse impacts on flooding conditions is to be minimised and any residual impacts managed in a manner acceptable to the affected land owners/stakeholders as an increase in flood levels may also impact future development costs.

4. Clarification is sought as to which drainage design policies are to be followed for the design of the drainage associated with the proposal.

5. The proposed drainage outlet X1 and associated pavement drainage will discharge into private property. Even though the impact is less than the pre-development stage, suitable arrangements need to be made with the property owners to mitigate or manage the impact.

6. In relation to the timing of the proposed Eskdale Creek basin, it is not known whether it will be constructed prior to the completion of the Old Wallgrove Road upgrade. Therefore, all interim drainage and flooding impacts need to be assessed and managed as part of project design.

7. In assessing the impacts on Eskdale Creek, the modelling needs to include the current Stages 1 and 2 precincts basin and be extended to the outlet of Eskdale Creek to include any cumulative impacts from the M7 basins. Also the 100 year ARI flow rates for Eskdale Creek are generally 20% higher than Council’s pre development conditions flow rate. Therefore, the base hydrologic models need to be reviewed to ensure valid basis for flow comparisons.

8. While there may not be any impacts due to the minor extent of changes in catchment parameters for Reedy Creek, hydrologic assessment should still be undertaken as part of the due process to justify the proposed management position.

9. All stormwater outlets to existing creeks should meet current NSW Office of Water guidelines.

Response

Sections 3.3.4, 6.7 and Figure 3-6 of the REF identifies that the proposal would utilise six permanent detention basins for operational water treatment prior to the


release of any water to the creeks or waterways. A number of these are existing basins and one is a regional stormwater detention basin that is proposed (yet to be constructed) by Blacktown City Council as part of the precinct planning. RMS would enter into further discussions and negotiations with Blacktown City Council on making financial contribution towards the cost of maintaining basins used by the proposal. As part of these negotiations a cost apportionment methodology would be agreed based on the impact caused by the road upgrade proposal. In response to the submission received, some additional drainage modelling and assessment was undertaken on the basins identified to be of concern in the submission. The detailed report is provided in Appendix C of this report. Some of the general findings include:

The proposal would not adversely impact the performance of Basins 1 and 2 (as identified in Figure 3-6 of the REF) in terms of both the rate and quality of stormwater discharging to the receiving drainage lines because the area of road surface that would contribute runoff to both basins is less than was assumed by the designers of the basins.

A review of available LiDAR survey data showed that the invert level of the outlet pipe for the existing detention basin on the northern side of Eskdale Creek (immediately west (upstream) of the Wallgrove Road crossing) is located above the peak post-upgrade 100 year ARI flood level in Eskdale Creek. On this basis it was concluded that the road upgrade works would not likely adversely affect the operation of the basin.

The impacts of the road upgrade on peak flows at Peak Flow Location Identifier A (refer Figure 5.1 of Appendix C in the REF) are discussed in Section 5.3.2 of the drainage investigation undertaken for the REF (Appendix C). Specific mention is made in this section of the report of the changes that will occur in peak flows with reference to pre development conditions. The adjoining landowner has been consulted with regard to the impact the proposed road upgrade will have on drainage patterns downstream of the road corridor. The impact of the road upgrade in terms of its immediate impact on peak flows and flood levels in the receiving drainage lines has been documented in the drainage investigations provided in Appendix C of the REF. Further supplementary flood modelling was undertaken to review the XP-RAFTS model files provided by Blacktown City Council to determine whether there was an inconsistency in the model used to derive flood hydrographs for the pre and post-developed Eskdale Creek catchment. Based on this finding, it is believed that Council’s pre-developed catchment model provides an under estimate of peak flows in the Eskdale Creek system. An independent review of the hydrologic and hydraulic assessment was undertaken as part of the REF. Based on the findings of the review, it was concluded that the assessment undertaken by the designers was reasonable. RMS considers the hydrology prepared for the proposal is therefore adequate and the need to undertake more detailed catchment modelling is not justified given the minor impact the road works will have on peak flood levels in Reedy Creek and the fact that existing development located in the zone of influence of the road works is not affected by floods with ARI’s up to 100 years. The treatment and final design of stormwater outlets will be determined during detailed design. NSW Office of Water guidelines would be referred to during the


development of these designs. During detailed design RMS would: 1. Further assess the impacts of the proposal on all existing and future detention

basins that would be utilised by the proposal. Any information regarding the impacts that the proposal would have on these basins would be provided and discussed with Blacktown Council. These assessments would ensure that the proposal does not adversely impact on the operation of these basins.

2. Undertake further analysis, based on the detailed design, of the invert level of the outlet pipe for the existing detention basin on the northern side of Eskdale Creek (immediately west (upstream) of the Wallgrove Road crossing) to confirm that the road works would not affect the operation of this basin.

3. Ensure flood modelling of the detailed design (including the interim arrangements if the regional basin is not built at opening of the proposal) does not provide for an increase in flood levels which may impact the adjacent development.

All drainage designs would comply with RMS guidelines and standards.

2.3.3 M7 Motorway basins

Submission numbers

1

Issue description

1. The REF does not clarify the maximum extent of both spills and stormwater entering the M7 Motorway basins, which could become an environmental issue if they exceed the maximum design capacity of the original design. WSO Co requests confirmation as to how the Old Wallgrove Road upgrade design is planning to incorporate the use of the M7 Motorway basins without posing possible risks to the maximum capacity allowable.

2. The REF refers to a possible flooding of the M7 Administration Offices, Incident Control Room, and associated computer storage areas, from the discharge of the first pavement drainage along Wallgrove Road. WSO Co requests further design detailing and clarification.

Response

Sections 6.6 and 6.7 of the REF outlines the hydrological and soil and erosion assessment for the proposal. In addition to Section 3, Figure 3-7 of the REF identifies the extent of the road upgrade works that would contribute to flow discharging to the existing M7 Motorway basins. This information was sourced from the Drainage investigation undertaken for the REF (provided in Appendix C of the REF). Section 5.4 of the REF drainage investigation (Lyall and Associates Report (2012)) sets out the findings of an investigation into the impact the discharge of road runoff would have on the operation of the M7 Motorway basins in terms of their water quality objectives. The investigation found that the road upgrade would not compromise the water quality objectives set as part of the original design of the basins. The investigation did find that the road upgrade would increase the depth of flow over the spillway of Basin 18.01 by between 50-100 mm for the 100 year average recurrence interval (ARI) event. With regard to incident management control, the existing basins incorporate provision for the capture of at least 50 m3 of spill material. It is RMS’ intention to utilise the existing basins to manage any spill material that might originate from the upgraded section of the road. Consultation with M7 Motorway operators has commenced for this proposed use of their detention basin and would continue


throughout detailed design. The capacity of the existing spillway would be checked during detailed design to confirm its suitability to cater for the increased depth of flow as a result of the proposal. Ongoing consultation with the Operators of the M7 Motorway would continue throughout detailed design to ensure appropriate information regarding the impacts of the proposal on the M7 basins is exchanged and negotiated. Section 5.4.2 of Drainage investigation (Appendix C) for the REF identified that the proposal may need to enlarge the cross sectional area of the grass lined channel which runs in a southerly direction along the western side of the Westlink M7 Operations Centre to prevent it from surcharging more frequently. This channel is located at the southern end of the M7 Motorway operations centre which includes shed and machinery storage facilities. Therefore the channel is well away from the Administration Office, Incident Control Room and associated computer storage areas, therefore flooding of these facilities is highly unlikely as a result of the proposal. However, as part of the detailed design, measures would be included to prevent the more frequent surcharge of the channel, thus ensuring that the proposed road upgrade would not exacerbate flooding conditions in any part of the Operations Centre.

2.4 Noise and vibration Submission numbers

1

Issue description

1. WSO Co requests measures in the design to minimise noise impacts on the Westlink M7 offices as a result of the proposal.

Response Section 6.3 of the REF identifies and assesses the potential noise impacts of the proposal. The Westlink M7 offices are located about 200 metres north of the proposal area. The NSW Road Noise Policy outlines the noise criteria for any sensitive receivers as a result of new or redeveloped roads. It identifies that sensitive receivers include residences, hospitals, schools, childcare facilities and places of worship. The Westlink M7 offices are not considered as a sensitive receiver and therefore do not qualify for noise attenuation treatments. Given the facility is located 200 metres away from the proposal area, and are currently bordered by the M7 Motorway on the eastern side and Wallgrove Road on the western side, it is likely that this facility already experiences high traffic noise levels, and the proposal would be unlikely to further contribute to these noise levels.


2.5 Property acquisition Submission numbers

1, 2, 3

Issue description

1. There is some inconsistency in the REF in relation to property acquisition. In general the intent appears to exclude batters from acquisition. However, Section 3.7 of the REF lists the acquisition area to include batters. In the event that batters are not acquired, then suitable easements need to be created over them.

2. The stakeholder does not object to the boundary for the property acquisition being the toe of the batter as referred to in the REF.

3. WSO co. requires confirmation that widening of Wallgrove Road does not encroach on Westlink M7 land.

4. The property acquisition should include the area required for the 4th leg to the north at the Old Wallgrove Road / Roberts Road intersection.

Response

Section 3.7 of the REF identifies the property acquisition that would be required for the proposal. This section of the REF does identify that ‘it is proposed to acquire from the edge of the 20 metre wide existing road reservation to the toe of batters…’. RMS acknowledge that there is some inconsistency in the REF as the assessment identified elsewhere that the batters would be handed back to property owners on completion of construction (including landscaping) to assist with the future setback requirements for adjacent development. Therefore, this submissions report confirms that it is the intention of RMS to restrict the acquisition to the land required for the proposal to the edge of the footpath reservation. RMS would propose to lease the land required for the batters during construction in agreement with the adjoining land owners and following construction of batters, landscaping and restoration of the affected area, to hand over the area of the batters back to the respective owners. RMS does not propose to acquire the land required for the batters as the batters could form part of the future landscape setback required by the development. Property acquisition and lease arrangements would be further discussed with property owners during detailed design and would be finalised prior to construction. All property acquisition would be undertaken in accordance with the provisions of the RMS' Land Acquisition Policy and the Land Acquisition (Just Terms Compensation) Act 1991. The widening of Wallgrove Road required as part of the proposal would be along the western side of the road corridor, away from the M7 Motorway land. It should be noted the only type of work that needs to be undertaken on M7 Motorway land as part of the proposal is line marking on the ramps to match the new lane configuration with the M7 and Wallgrove Road intersection and the M7 and mini-link road intersection. Therefore, no property acquisition would be required for the proposal of land under the control of Westlink M7 at this stage. If any changes are made during detailed design that would change this position, consultation with the necessary stakeholders would be undertaken.

This proposal is consistent with the Precinct Plan developed by Blacktown City


Council and the Department of Planning and Infrastructure, and with the approved Part 3A Concept Plan for the Erskine Park Link Road Network. These plans do not identify a fourth leg to the intersection of Roberts Road/Old Wallgrove Road, and this additional leg is not included as part of this proposal. Therefore, no additional land acquisition would be required at the intersection of Old Wallgrove Road and Roberts Road. Any future changes to the Precinct Plan that require an additional access point off the intersection of Old Wallgrove Road and Roberts Road is a matter for Blacktown City Council and the Department of Planning and Infrastructure.

2.6 Planning for future work within the M7 Motorway Submission numbers

1

Issue description

1. The traffic report does not model the current and future queuing issues at the M4 Motorway exit/entry points and the Horsley Drive intersection.

Response

Section 6.1 and Appendix F of the REF identifies the traffic assessment undertaken for the proposal. The M4 Motorway, including the entry and exit ramps for Wallgrove Road/M7 are located about one kilometre north of the proposal. No works are proposed to occur on the M4 Motorway or the entry/exit ramps as part of the proposal. The Horsley Drive/Wallgrove Road/M7 intersection is located about three kilometres south of the proposal area. No works are proposed at this intersection as part of the proposal. The only works to be undertaken within the M7 Motorway corridor would be changes to the existing line marking at the entry/exit ramps to meet the new lane configurations at the Wallgrove Road intersections. The traffic modelling undertaken for the REF and subsequent modelling for the submissions report does not identify that the proposed changes to the line marking within the M7 would have any impacts on the current or future functioning of the M7. The future impact on the operations of the M7 Motorway as a result of further development within the WSEA would be assessed as part of future proposals. There would be on-going discussions and negotiations with the WSO Co as the employment hub develops further, especially with the planning for the Southern Link Road. Modelling undertaken for the REF did include ramps from the M4 to the M7 but did not include the Horsley Drive Interchange, as this interchange is not considered to be within the scope of works of this study. Further modelling of this section of the M7 has been undertaken by AECOM on behalf of Department of Planning and Infrastructure and is documented in Southern Link Road Transport Assessment (2011). This document identified that Horsley Drive interchange was likely to be a key constraint for the M7 and recommended widening of The Horsley Drive to provide an additional 2 eastbound lanes in the vicinity of the existing interchange. Any works to this intersection/interchange is outside the scope of the proposed upgrade of Old Wallgrove Road.


2.7 Staging of works Submission numbers

2

Issue description

1. Council supports the idea of the mini-link road to be constructed first and opened to traffic. This would allow some traffic to be diverted to the mini-link road and Capicure Drive, which would potentially reduce the traffic on Old Wallgrove Road during construction.

Response

Section 3.4.1 of the REF identifies the potential general construction staging of the proposal in 3 main stages. The final construction staging has not yet been finalised. This would be undertaken at the detailed design stage and by the contractor prior to construction. RMS acknowledged councils’ support of the approach to build the mini- link road at the beginning to minimise impacts to traffic movements throughout construction. While the three identified stages of construction may not be the final construction approach, consideration would be given to minimise traffic impacts when deciding on construction staging, this would include construction of mini-link road as early works.

2.8 Stakeholder and community consultation Submission numbers

1, 2

Issue description

1. Concerns raised that not all adjoining landowners are included in the communications strategy and suggests that all adjoining land owners be included as the proposal would impact on future development potential of the adjoining parcels of land.

2. RMS should be interacting with Westlink M7 about all of their interface projects, current and planned.

3. RMS should continue to consult Blacktown City Council during detailed design.

Response

Section 5 of the REF identifies that RMS has consulted with WSO Co and local council in relation to the proposal throughout the development of the concept design. This section also identifies any issues/concerns raised by these stakeholders throughout this consultation and where these issues have been addressed in the REF. Further WSO Co and Blacktown City Council were provided with copies of the REF for review during the display period and both made submissions which have been considered as part of this report. Section 5.6 of the REF also commits to ongoing consultation with stakeholders throughout the detailed design stage of the proposal and that a communications management plan would be developed to identify ongoing consultation throughout


construction. RMS has consulted with the WSO Co for this proposal. However, any future consultation for other major projects, both current and future is outside the scope of this proposal. RMS is committed to consulting with relevant stakeholders for all major projects and has policies in place to ensure appropriate consultation is undertaken when required. As outlined in section 2 of this report, the REF was placed on public display for a one month period, allowing for review and comment from the general public. All adjacent land owners had the opportunity to review the proposal and make submissions. The stakeholder list identified in the Communications Strategy in Appendix D of the REF was developed at the beginning of the proposal. A number of properties have changed ownership since this time. This list would be updated as required for any future consultation. All adjoining land owners would continue to be consulted throughout the development of the proposal. In particular any impacts to adjacent land owners would be discussed and negotiated with the owners, and any property acquisition completed prior to construction.


3 Additional assessment

Additional studies were carried out to address issues related to traffic and access, and flooding and drainage. The scope, rationale and outcome of the additional assessments are summarised below in sections 3.1 and 3.2 and details provided in Appendix B and Appendix C.

3.1 Additional traffic and access assessment Scope An additional assessment was undertaken to update the strategic traffic model to address the comments of respondents to the REF. The additional investigations include the following: Adoption of a higher trip generation rate for the Ropes Creek precinct from 10 to

21 trips per hectare for a two-hour peak period. Sensitivity testing with and without the extension of Archbold Road from Erskine

Park Link Road with east facing ramps at the M4 Motorway. Revision of the traffic demand distribution in the study area based on updated

cordon matrices.

From this additional investigation work an approximate time frame for widening works required to be undertaken within the M7 Motorway corridor was also determined. Outcome The increase in the trip generation rate for the Ropes Creek precinct to 21 trips per hectare for two-hour peak period results in an additional 1,000 trips per hour in the 2-hour peak period. Based on this additional trip generation, the strategic traffic modelling identified that in order for all intersections in the proposal to perform at an acceptable level of service (LoS D or better), Archbold Road, being adjacent to Ropes Creek precinct, would have to be extended from Erskine Park Link Road to the Great Western Highway with east facing ramps at the M4 Motorway by 2021. In addition, traffic modelling work was extended to test the adequacy of the proposal for the ultimate development scenario (2031) for the WSEA and to determine an approximate timeframe for further works to be undertaken within the M7 Motorway corridor. The traffic forecast shows that the following works would be required between 2021 and 2026: Construction of a new Southern Link Road, south of the Sydney Water Pipelines,

connecting Mamre Road and Wallgrove Road. Widening of the M7 Motorway southbound to four lanes between the M4

Motorway and Old Wallgrove Road. Widening of the existing M7 southbound off ramp to two lanes to connect with Old

Wallgrove Road. The traffic modelling also identified that the intersection of Old Wallgrove Road and Wallgrove Road is likely to be approaching capacity in the morning peak period by 2026 and that queues from this intersection are likely to extend back to the M7 Motorway. Further assessment will be required to determine the works that will be


required to address this queuing onto the M7 Motorway from Wallgrove Road. This would likely be part of a separate proposal to be developed in the future. Based on the additional traffic impact assessment, it has been concluded that the concept design undertaken as part of the REF has sufficient mid block capacity to serve the traffic demand for the year 2021 (design year) even under a higher trip generation rate adopted for the Ropes Creek precinct as requested by Blacktown City Council. Furthermore, the additional traffic assessment concluded that no works other than line marking on the Motorway ramps as detailed in the concept design would be required within the M7 Motorway corridor, at least up to the design year. However, in order for all intersections as part of the proposal to function at a level of service of at least D, it has been concluded that Archbold Road has to be extended from Erskine Park Link Road to the Great Western Highway with east facing ramps at the M4 Motorway. Archbold Road is part of the Western Sydney Employment Hub Erskine Park Link Road Network concept plan environmental assessment (WSEA concept plan), which includes the upgrade to Old Wallgrove Road (this proposal). This concept plan was approved in August 2009 by the Minister for Planning under (former) Part 3A of the Environmental Planning and Assessment Act 1979.

3.1.1 Additional management and mitigation measures

No additional management and mitigation measures are recommended from the additional assessment.

3.2 Additional flooding and drainage assessment Scope

The scope of additional investigation undertaken by Lyall and Associates to address comments from respondents to the REF comprised the following tasks:

Investigate further the impact of the proposal on the M7 Motorway basins and the Administration Offices.

Investigate further the impact of the proposal on existing and proposed Council basins in the study area.

Assess the need for a temporary erosion and sediment control basin proposed east of the intersection of Old Wallgrove Road and Eastern Creek Drive.

Outcome The investigation found that the road upgrade and widening will not compromise on the water quality objectives set as part of the original design of the M7 Motorway basins. However, it was found that the proposal will increase the depth of flow over the spillway of Basin 18.01 by between 50-100mm for the 100 year average recurrence interval (ARI) event. With regard to the incident management control, the existing M7 Motorway basins incorporate provision for the capture of at least 50 m3 of spill material and it is therefore RMS’ intention to rely on the existing provision to manage any spill that may originate from the proposal. It should be noted that the channel referred to in the submission is located at the


southern end of the M7 Operations Centre, well away from the Administration Offices. The supplementary investigation together with construction staging plans has found that the temporary erosion and sediment control basin proposed east of the intersection of Old Wallgrove Road and Eastern Creek Drive could be omitted from the erosion and sediment control strategy for the road upgrade proposal, in favour of more localised measures as stated in Lyall and Associates report (Appendix C). Supplementary flood modelling was undertaken to review the XP-RAFTS model files provided by Blacktown City Council to determine whether there was an inconsistency in the model used to derive flood hydrographs for the pre and post-developed Eskdale Creek catchment. Based on this finding, it is believed that Council’s pre-developed catchment model provides an under estimate of peak flows in the Eskdale Creek system. A sensitivity analysis was undertaken whereby the HEC-RAS model for Eskdale Creek was re-run using Council’s revised peak flow estimate of 24.2 cubic metres per second. The modelling showed that there is less than a 20 millimetre difference in peak flood levels in Eskdale Creek for the two peak flow estimates. Based on this finding, it was concluded that the adoption of the reduced peak 100 year ARI flow estimate of 24.2 cubic metres per second would not alter the findings of the REF. The DRAINS model developed as part of the REF was re-run assuming the new pavement drainage system for Old Wallgrove Road discharged directly to Eskdale Creek. The results of the modelling show that the peak 100 year ARI flow in Eskdale Creek at the Wallgrove Road crossing would not be increased by the proposal.

3.2.1 Additional management and mitigation measures

The additional management and mitigation measures recommended from the additional assessment include the need for further hydrological and hydraulic assessment to be undertaken during detailed design including sizing of the grass lined channel to prevent more frequent surcharge of the channel that runs adjacent to the M7 Operations Centre.


4 Environmental management

The REF for Old Wallgrove Road Widening (Roberts Road – Wallgrove Road), Eastern Creek identified the framework for environmental management, including management and mitigation measures that would be adopted to avoid or reduce environmental impacts (Section 7 of the REF). Should the proposal proceed, environmental management will be guided by the framework and measures outlined below.

4.1 Environmental management plans (or system) A number of safeguards and management measures have been identified in order to minimise adverse environmental impacts, including social impacts, which could potentially arise as a result of the proposal. Should the proposal proceed, these management measures would be incorporated into the detailed design and applied during the construction and operation of the proposal. A Contractors Environmental Management Plan (CEMP) would be prepared to describe safeguards and management measures identified. These plans would provide a framework for establishing how these measures would be implemented and who would be responsible for their implementation. These plans would be prepared prior to construction of the proposal and must be reviewed and certified by RMS environment staff, Sydney Region, prior to the commencement of any on-site works. The CEMP will be a working document, subject to ongoing change and updated as necessary to respond to specific requirements. The CEMP would be developed in accordance with the specifications set out in the RMS QA Specification G36 – Environmental Protection (Management System), RMS QA Specification G38 – Soil and Water Management (Soil and Water Plan) and the RMS QA Specification G40 – Clearing and Grubbing.

4.2 Summary of safeguards and management measures Environmental safeguards outlined in this document would be incorporated into the detailed design phase of the proposal and during construction and operation of the proposal, should it proceed. These safeguards would minimise any potential adverse impacts arising from the proposed works on the surrounding environment. The safeguards and management measures are summarised in Table 4.1.


Table 4.1: Summary of site specific environmental safeguards

No. Impact Environmental safeguards Responsibility Timing

1 General All environmental safeguards must be incorporated within the following documents:

Project Environmental Management Plan

Detailed design stage

Contract specifications for the proposal

Contractor’s Environmental Management Plan.

RMS Project manager Pre-construction

2 General A risk assessment must be carried out on the Proposal in accordance with the RMS Audit Pack and OSD risk assessment procedures to determine an audit and inspection program for the works. The recommendations of the risk assessment are to be implemented.

A review of the risk assessment must be undertaken after the initial audit or inspection to evaluate if the level of risk chosen for the project is appropriate.

Any works resulting from the proposal and as covered by the REF may be subject to environmental audit(s) and/or inspection(s) at any time during their duration.

RMS Project manager and Regional

Environmental staff

Pre-construction

After first audit

3 General The environmental contract specification must be forwarded to the RMS Regional Environmental Officer for review at least 10 working days prior to the tender stage.

A contractual hold point must be maintained until the CEMP is reviewed by the RMS Regional Environmental Officer.


4 General The RMS Project Manager must notify the RMS Regional Environmental Officer, Sydney Region at least five days prior to work commencing.




5 General All businesses and residences likely to be affected by the proposed works must be notified at least five working days prior to the commencement of the proposed activities.


6 General Environmental awareness training must be provided, by the contractor, to all field personnel and subcontractors.

Construction contractor Pre-construction and construction

7 Utility services Prior to construction, existing utilities would be identified and either avoided or protected for the duration of construction.

Construction contractor Pre-construction and construction

8 Resource use and traffic minimisation

Earthworks quantities would be balanced as far as practicable during detailed design to ensure that the transfer of material along the external road network is minimised.


9 Construction traffic impacts

Prior to construction, a traffic management plan would be prepared to outline management measures during construction. These measures describe how:

Traffic control would be provided to manage and regulate traffic movements during construction.

To notify road users about traffic conditions/ disruptions.

To consult with property owners on property access disruptions.

Disruption to all road users during construction would be kept to a minimum.

Construction and delivery vehicles entering or leaving the site compound and/or stockpile sites would use designated haulage routes identified in the plan under traffic control. These movements would be restricted to non-peak traffic periods as specified in the plan to minimise movements on adjacent roads during

Construction contractor Pre-construction



construction.

Appropriate traffic management measures would be implemented that could see a reduction in the speed limit along the extent of the construction site and localised temporary delays along Old Wallgrove Road and local road intersections.

Consideration would be given to the staging of construction to minimise impact to existing traffic flow. This would include but not be limited to the construction of the mini-link road at stage 1 to allow it to open to traffic while other areas of the upgrade are constructed, where possible.

The function of intersections under construction arrangements would be monitored and signalisation of these intersections changed as required to ensure efficient traffic movement, particularly during peak hours.

10 Local road access impacts

Property access to and from Old Wallgrove Road, opposite Roberts Road intersection would be considered as part of detailed design. If any changes are made to the proposal, the RMS Regional Environment Officer would be consulted to identify any further environmental assessment that may be required for any changes.


11 Existing connecting streets would have their accesses maintained during construction. However, should accesses need to be obstructed during construction, alternatives would be put in place for the duration of the disruption.

Construction contractor Construction

12 Access impacts

Consultation would be undertaken with the property owners to minimise any access impacts.


13 Closure of RMS would continue to consult with the relevant landowner of RMS Project Construction



existing property access onto Old Wallgrove Road

the timing of closure of the access onto Old Wallgrove Road. Manager/Construction contractor

14 Public transport

Consultation would be undertaken with Westbus to identify temporary bus stop locations on Old Wallgrove Road to limit impacts or temporarily relocate the stops during construction.


15 Impacts to Cumberland Plain Land Snail

Prior to construction, a qualified ecologist is to undertake a targeted survey of Cumberland Plain Land Snail (Meridolum corneovirens), and if present, a translocation plan would be prepared, in consultation with Office of Environment and Heritage.


16 Construction impacts to native vegetation in and outside the proposal footprint.

Exclusion fencing would be established around areas of vegetation outside of the approved clearing areas (including the area of River Flat Eucalyptus and Casuarina grove) for the duration of construction. Fences would be maintained at all times, and construction staff would be advised of their purpose and instructed to stay out of these areas.


17 Parking and vehicular access off existing roads would only be in designated areas and away from mature trees.


18 Vegetation removal would be minimised where possible. Construction contractor Construction

19 Impacts to fauna

Any native vegetation clearing would be supervised by an experienced ecologist to avoid impacts on fauna.


20 Any incident involving fauna would be reported to WIRES. Construction contractor Construction

21 Impacts to waterways

Appropriate erosion and sedimentation controls would be installed prior to any vegetation removal or earthworks near




Reedy and Eskdale creeks, with exclusion zones established to prevent parking or other vehicle movement inside the riparian vegetation.

22 All cleared areas would be progressively stabilised. Construction contractor Construction

23 Spread of weeds

All vehicles and equipment would be cleared of soil and vegetation when leaving the site to avoid transfer of weeds and soil borne diseases.


24 Construction noise and vibration impacts

Should the child care centre proposed to be located in Southridge Street be operational during construction of the proposal, prior notice of the construction program would be given and the centre would be kept informed throughout the construction period and provided with a name and contact number for construction noise information and complaints. Noise complaints would be dealt with promptly.


25 Mobile equipment would be fitted with noise control equipment, where possible.


26 A construction noise and vibration management plan would be prepared prior to construction works. This plan would include construction hours and measures to minimise noise impacts to sensitive receivers.


27 Impacts to known Aboriginal heritage sites

An Aboriginal Site Impact Recording form should be completed and lodged with the AHIMS registrar, detailing the test excavations undertaken within the Conservation Area PAD/artefact scatter.

RMS Project manager Pre- construction

28 Due to the low significance of the artefacts recovered in the test excavations, they are unlikely to be suitable for lodgement with the Australian Museum. The Project Archaeologist




(AHMS) will, therefore, ask registered Aboriginal parties if they would like to take control and care of the artefact. If no agreement is reached, the artefacts would be returned to RMS and recommended that they be re-buried within the subject area following completion of the works.

29 The section 90 Aboriginal Heritage Impact Permit should be sought.


30 Impact to unknown/ undiscovered Aboriginal heritage sites or change to impacts

If the boundaries of the proposal are revised to include areas not investigated as part of the AHMS cultural heritage assessment, advice would be sought from RMS Regional Environmental Officer on the need for further assessment of the impacts.


31 In the event that previously undiscovered Aboriginal objects, sites or places (or potential Aboriginal objects, sites or places) are discovered during construction, all works in the vicinity of the find should cease and RMS should implement their Standard Management Procedure: Unexpected Archaeological Finds (July, 2012) for addressing un-identified Aboriginal objects.

RMS Project manager/Construction contractor

Construction

32 Ongoing consultation with the Aboriginal community

RMS would continue to notify registered Aboriginal parties of the progress of the proposal.

RMS Project manager Construction

33 Construction management of heritage sites

RMS would advise all on-site construction personnel and contractors, of the relevant heritage legislative requirements.


Construction



34 Impacts on human remains

Should suspected human skeletal material be identified, all works should cease immediately and RMS should implement their Standard Management Procedure: Unexpected Archaeological Finds (November, 2011) for managing human skeletal remains.


Construction

35 Non Aboriginal heritage impacts

If any unknown non-Aboriginal heritage items are encountered during construction, work would cease in the area of the find and RMS would implement their unexpected finds procedures. Works in the area would not recommence until the appropriate approvals or clearances have been obtained.


36 Managing contaminated lands

Appropriate measures would be implemented as part of the CEMP to manage saline soils and minimise any impacts associated with contaminated soils.


37 Run off quality from the proposal

Detailed design would incorporate appropriate measures to contain and manage the quality of road runoff from the proposal.


38 Identification of contaminated water

Should any de-watering be required, water would be tested for contaminants. If found, appropriate management measures would be put in place.


39 Erosion and sediment control during construction

The construction site compound would be restored with suitable native vegetation species once construction is complete.


40 Erosion and sedimentation control plans would be developed in accordance with the Managing Urban Stormwater (Landcom 2004) and Managing Urban Stormwater: Soils and Construction, Volume 2D, Main Road Construction (DECC 2008). The plan is to be prepared taking into account staging




of the works and would include (but not limited to) the following:

Construction catchments

Water flow paths for the construction area and adjacent property

The likely run-off from each road sub-catchment

Controls or diversion drains to minimise the off-site mixing with on-site water

The locations and sizing of sediment basins

The direction of runoff and drainage points during each stage of construction

Calculation of work area and soil loss. Construction basin location and measures to direct on site runoff into the basin

Basin calculation

Standard drawings for sediment controls such as sand bags and batter shoots

Proposed staging plans for the project to ensure appropriate erosion and sediment control is possible

Construction staging and soil opened/exposed during construction would be limited to the capacity of the construction sediment basin for that area, in accordance with the Blue Book (Landcom 2004, Volume 2D).

41 The area to be cleared for the construction would be minimised as far as practicable, particularly around Reedy and Eskdale creeks to minimise the potential for erosion and sedimentation.




Appropriate erosion and sedimentation controls would be put in place to also minimise impacts to the creeks.

42 Maintaining water quality during operation

Water quality basins and structures would be appropriately cleared and maintained.

RMS Project manager Operation

43 Spill procedures

Emergency spill kits would be kept on site at all times. All staff would be made aware of the location of the spill kit and trained in its use.


44 If a spill occurs, the RMS’ Environmental Incident Classification and Management Procedure would be followed and the RMS Project Manager notified as soon as practicable.


45 Any refuelling of vehicles and equipment on site would be undertaken on an impermeable surface, within a bunded area located at least 40 metres away from water bodies and surface water drains. Any fuel, oils or other liquids stored on site would be stored in an appropriately bunded area away from water bodies.


46 Minor repairs or servicing for machinery and equipment on-site may be necessary. However, significant repairs or servicing would take place off site.


47 Use of existing detention basins

Further assess the impacts of the proposal on all existing and future detention basins that would be utilised by the proposal. Any information regarding the impacts that the proposal would have on these basins, including stormwater hydrologic and hydraulic issues, would be provided and discussed with local council. These assessments would ensure that the proposal does not adversely impact on the operation of these basins.

RMS Project manager Detailed design



Further analysis would be undertaken based on the details of the invert level of the outlet pipe for the existing detention basin on the northern side of Eskdale Creek (immediately west (upstream) of the Wallgrove Road crossing) to confirm that the road works would not affect the operation of this basin.

Further flood modelling would be undertaken (including the interim arrangements if the regional basin is not built at opening of the proposal) to make sure the proposal does not cause an increase in flood levels which may impact the adjacent development.

The capacity of the existing spillway for the M7 Motorway operational detention basin would be checked during detailed design to confirm its suitability to cater for the increased depth of flow as a result of the proposal. Ongoing consultation with the managers of the M7 Motorway would continue throughout detailed design to ensure appropriate information regarding the impacts of the proposal on the M7 basins is exchanged.

During detailed design, measures would be included (including review of sizing of the cross sectional area of grassed lined channels) to prevent the more frequent surcharge of the grass lined channel located on the western side of the Westlink M7 Operations Centre (running in a southerly direction) to prevent it from surcharging more frequently, thus ensuring that the proposed road upgrade would not exacerbate flooding conditions in any part of the Operations Centre.

RMS would enter into further discussions and negotiations with Blacktown City Council on making financial contribution towards the cost of maintaining basins used by the proposal. As part of these negotiations a cost apportionment methodology would be agreed based on the impact caused by



the road upgrade proposal.

47 Impacts to watercourses

All refuelling or minor repairs to be undertaken on-site are to occur within an impermeable, bunded area at least 40 metres from any watercourse or drainage line.


48 Property acquisition

Ongoing consultation with directly affected landowners would occur throughout the RMS pre-construction period.


49 Land acquisition would be carried out in accordance with the Land Acquisition (Just Terms Compensation) Act 1991.


50 Construction property impacts

On completion of construction activities, land used for temporary construction sites, stockpiles and sedimentation basins would be revegetated and left in a stable condition.


51 Dust generation

All disturbed areas would be stabilised as soon as practicable to prevent or minimise windblown dust. This may include progressive hydro-mulching of disturbed areas as works are completed. Revegetation in accordance with an approved landscape concept plan would be required.


52 Water sprays, sprinklers and water carts would be employed if needed to adequately dampen work areas and exposed soils to minimise off-site dust emissions.


53 Maintenance and use of construction equipment

Construction equipment would be kept in a good operating condition. Construction equipment would be properly maintained to ensure exhaust emissions comply with the Protection of the Environment Operations Act 1997.


54 Vehicle and machinery movements would be restricted to designated areas during construction.


55 Site exit(s) would include controls (e.g. rumble grids) to Construction contractor Construction



remove mud from vehicles.

56 Vehicles transporting material to and from the site would be covered immediately after loading to prevent windblown dust emissions and spillages.


57 Stockpile management

Stockpiles and handling areas would be maintained in accordance with the RMS Stockpile Site Management Guidelines (2011).

Construction contractor

Construction

58 Stockpiles would be managed to minimise windblown or traffic generated dust. Areas that may be inaccessible by water carts would be kept in a condition that minimises windblown or traffic generated dust using other means such as water cannons, overhead sprinklers, tarpaulins or dust sealants.


59 Bridge aesthetics

Bridges over Reedy and Eskdale creeks would be designed to be similar to the existing structures.


60 Planting and landscape strategy

As much natural vegetation within the study area would be retained as possible.


61 Any landscaping would be undertaken with local indigenous plant species as per the indicative planting schedule in the Urban Design Report and Landscape Character and Visual Impact Assessment (AECOM 2012).


62 Landscaping would be undertaken progressively as works are completed.


63 Riparian corridor restoration around Reedy and Eskdale creeks around the bridge widening would be undertaken.


64 Batters would be rounded as much as possible and where practicable vegetated to transition into the adjoining land.




65 Manage landscaping

Monitoring and maintenance of landscaped areas would be undertaken for 12 months.

Construction contractor Operation

66 Amenity impacts

The community would be kept informed about the proposal and provided information on construction progress, access and traffic condition changes.

Construction contractor Pre-construction/ construction

67 Access disruption

Property access would be maintained for the duration of construction. Should temporary or alternative access be required, this would be provided in consultation with the affected landowner.


68 Local road closures would be minimised as much as possible. Construction contractor Construction

69 Traffic disruption

Where possible, transportation of materials for the proposal would be undertaken outside of peak traffic times.


70 Amenity impacts associated with the construction of the proposal would be managed in accordance with the CEMP.


71 Construction materials and other products and services would be locally sourced, as far as practicable.


72 Management of construction waste

Construction waste would be managed through the waste hierarchy established under the Waste Avoidance and Resource Recovery Act 2001 (WARR). All waste generated during construction would be disposed of in accordance with the requirements of Waste Classification Guidelines (DECC 2008). Waste management measures would be developed for the proposal and would form part of the overall CEMP.


73 Site inductions would include training in waste minimisation principles.


74 A waste register would be maintained, detailing types of waste Construction contractor Construction



collected, amounts, date/time and details of disposal.

75 Identification of recycling and re-use of materials

Where practicable, waste products would be reused on site, including:

Earthworks material as fill embankments

Sub-grade layers and other material for batter extensions

Top-soil for landscaping

Cleared vegetation would be mulched, chipped or composted to be used as sediment filter fences, landscaping or land rehabilitation

Crushed concrete as road base, footings, retaining walls or drainage.


76 Regular visual inspections would be conducted to ensure that work sites are kept tidy and to identify opportunities for reuse/recycling.


77 Sourcing of recycled materials

Where possible and compliant with RMS specifications, secondary waste materials such as fly ash, steel slags and recycled aggregate would be used instead of virgin quarried construction materials. Use of these materials would be dependent on the proximity of the site to sources of recycled materials to avoid excessive transport costs and transport related greenhouse gases.


78 RMS contractors would be required to propose recycled-content materials where they are cost and performance competitive.


79 Disposal of waste

Materials not reused on site would be stockpiled in appropriately bunded areas (in accordance with the RMS




Stockpile Site Management Guidelines (2011) prior to being recycled at appropriate specialised off-site recycling contractors.

80 Containers for litter and other wastes would be provided and contents disposed of at a suitable waste disposal station.


81 Chemical, fuel and lubricant containers, and solid and liquid wastes would be disposed of in accordance with the requirements of the OEH.


82 Climate change impacts

The impact of increased intensity flood events and stormwater runoff as a result of climate change would be considered further during the detailed design of culvert crossings and stormwater drainage systems.


83 Improving energy efficiency and sustainability

Energy (fuel/electrical) efficiency would be considered when selecting equipment.


84 Equipment would be regularly maintained to retain fuel efficiency.


85 Where feasible, biofuels would be used (biodiesel, ethanol, or blends such as E10 and B80), to reduce greenhouse gas emissions from construction plant and equipment.


86 Vegetation clearance would be minimised and revegetation would be undertaken as much as practicable.


87 Energy efficient work practices would be adopted to limit energy use, including conducting energy conservation awareness programs for all site personnel and undertaking energy audits to identify and address energy waste.


88 Plant and office-based equipment (including lights and Construction contractor Construction



computers) would be operated in an efficient manner and would be regularly maintained.

89 If available, electrical energy derived from a renewable energy source accredited by the National Green Power Accreditation Steering Group (or equivalent) would be used for the supply of on-site electrical energy required during construction.


90 Locally-sourced materials and staff would be used wherever possible, to reduce transport related emissions.


91 Recycled materials, such as replacement of cement with fly ash, recycled aggregate, and recycled content in steel, would be used to minimise the lifespan impact of greenhouse gas emissions in production where practicable.


92 Procedures for managing hazards and wastes

Hazards and risks associated with the construction of the proposal would be identified before construction and management measures would be implemented during construction through a CEMP.


93 A site-specific safety management plan would be prepared to manage potential occupational health and safety hazards. The plan would identify hazards on-site and hazard control measures to adequately protect people from risk of injury or illness. This would include:

Procedures for manual handling of heavy loads

Procedures to comply with legislative and industry standard requirements for the safe handling and storage of hazardous substances and dangerous goods.


94 A maintenance and inspection program to maintain and audit Construction contractor Construction



construction controls.

95 Storage of materials

Areas for storage of hazardous liquids to be bunded and secured, with any spills collected and disposed of off-site.


96 Minimal amounts of hazardous materials would be stored on site.


97 Hazardous materials

Potentially hazardous and contaminating activities to be conducted in bunded areas to prevent discharge into watercourses.


Old Wallgrove Road Widening (Roberts Road – M7 Motorway), Eastern Creek Review of environmental factors 42 Submissions Report

4.3 Licensing and approvals Table 4.2: Summary of licensing and approval required.

Requirement Timing Aboriginal Heritage Impact Permit from OEH to disturb Aboriginal heritage sites and items

Prior to any subsurface investigations and work.

Old Wallgrove Road Widening (Roberts Road – M7 Motorway), Eastern Creek Review of environmental factors 43 Submissions Report

5 References

Aurecon 2012, Old Wallgrove Road Widening (Roberts Road to Wallgrove Road), Eastern Creek, Review of Environmental Factors. AECOM 2011, Western Sydney Employment Area Southern Link Road Network Strategic Transport Assessment. GHD 2012, Old Wallgrove Road Upgrade (Roberts Road - M7 Motorway) Traffic and Transport Report, Sydney. GHD 2013, Proposed Widening of Old Wallgrove Road, REF and Concept Design Response to REF Submissions. Lyall and Associates 2012, Old Wallgrove Road Upgrade, Eastern Creek, Drainage Investigation. Lyall and Associates 2013, Proposed Upgrade of Old Wallgrove Road - Response to Flood and Drainage Related Comments Contained in Stakeholder Submissions to the REF.

National Environmental Consulting Services 2009, Western Sydney Employment Hub Proposed Erskine Park Link Road Network Concept Plan Environmental Assessment- Submissions Report and Preferred Project Report.

Appendix A

Invitation to comment Table A-1. Method by which local businesses, community groups and Government agencies were invited to comment on REF

Community update provided

Hardcopy of REF provided

Electronic invitation to comment letter and REF provided

Department of Planning and Infrastructure

Various land owners WSO Co

Office of Environment and Heritage

Blacktown City Council Jacfin Pty Ltd

NSW Treasury Department of Planning and Infrastructure

Australand

Department of Industry and Investment

WSO Co Brickworks

Sydney Catchment Authority

Goodman Pty Ltd

Blacktown Council Network Consulting Pty Ltd

Fairfield Council Penrith City Council Member for Mulgoa Member for Smithfield Member for Prospect Various land owners Sydney Water Endeavour Energy Telstra AGL NSW Police NSW Ambulance NSW Fire Brigade Transgrid WSO Co Bus About West Bus Busways Linfox Coles Woolworths Pickfords Packcentre Trust Company of Australia

Hasbro

Community update provided

Hardcopy of REF provided

Electronic invitation to comment letter and REF provided

CSR Valad Paclib Industrial BlueScope Steel GPT RE Limited

Appendix B

Supplementary traffic and access assessment

21 February 2013

Matty Mathivanar Senior Development Manager Roads and Maritime Services 27-31 Argyle Street Parramatta NSW 2124

Our ref: 21/22191 188178 Your ref:

Dear Matty

Proposed Widening of Old Wallgrove Road REF and Concept Design Response to REF Submissions

1 Introduction

This letter outlines the response to traffic and transport comments made in submissions to NSW Roads and Maritime Services (RMS) regarding the Review of Environmental Factors (REF) for the proposed widening of Old Wallgrove Road. The REF was put on public display in October 2012 and outlined the

concept design for the widening of Old Wallgrove Road between Roberts Road and the M7 Motorway and included a traffic and transport assessment of the impacts of the proposed widening.

Comments relating to traffic and transport analysis undertaken as part of the REF were received from the

following stakeholders:

Westlink M7: in a letter dated 23 November 2012; and

Blacktown City Council: in a letter dated 26 November 2012.

Responses to the issues raised in these submissions, as well as further traffic and transport analysis

undertaken to support these responses are detailed in this letter.

2 Background

2.1 Modelling Process

GHD have undertaken three-tiered traffic modelling as part of the REF for the proposed widening of Old

Wallgrove Road that included the following modelling steps:

1. Strategic traffic modelling of the surrounding Western Sydney Employment Area (WSEA), including the M7 and M4 Motorways, Wallgrove Road, Old Wallgrove Road and surrounding roads.

2. Paramics micro simulation traffic modelling of Wallgrove Road, Old Wallgrove Road and the M7

Motorway and surrounding local roads.

3. SIDRA intersection modelling of the key intersections along Wallgrove Road and Old Wallgrove Road.

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Assessment of the concept design was undertaken on the basis of the performance of key intersections in the study area (based on the intersection level of service) with particular attention paid to minimising the impacts of intersection queues on the surrounding Motorways (M4 and M7) and the Old Wallgrove

Road corridor. Intersections were designed to achieve an intersection level of service of D or better and and to minimise queues onto the M7 and M4 Motorways for the design year (2021). Further testing was also undertaken for the 2031 horizon year to determine the Old Wallgrove Road corridor requirements to

meet the demand generated by the full development of WSEA.

Comments on the REF traffic and transport assessment from both Blacktown City Council and Westlink M7 identified the need to undertake further traffic modelling to address the following issues:

Sensitivity testing to a change in the assumed traffic generation rate for the Ropes Creek Precinct, from 10 trips per hectare to 21 trips per hectare.

Further investigation of the widening requirements for the M7 Motorway identified in the 2031 horizon year testing.

Identification of when widening of the M7 Motorway is required.

To address these issues, further traffic modelling was undertaken for each of the modelling years. A summary of the sensitivity testing undertaken as a response to the REF comments is provided below.

2.2 Revised Strategic Modelling

The strategic traffic model has been updated to include the following:

Revised cordon matrices from the RMS Sydney Strategic model to include the proposed Archbold Road east facing ramps and updated 2021 forecast traffic flows;

Extension of the model to cover the proposed interchange of Archbold Road with the M4 Motorway

Inclusion of the M4 east-facing ramps at Archbold Road for the 2021 year and onwards; and

Revision of the strategic model traffic demand to include revised traffic distributions for land use

within the study area (based on revised cordon matrices from RMS) and revised trip generation rates for the Ropes Creek Precinct from 10 trips per hectare to 21 trips per hectare.

The revised strategic traffic modelling showed that the extension of Archbold Road with east facing

ramps on the M4 Motorway would result in following:

More traffic heading west along Old Wallgrove Road;

Less traffic heading east on Old Wallgrove Road; and

Greater traffic demand to the west along Archbold Road;

Overall, the inclusion of the Archbold Road east facing ramps to the M4 transfers some 800 vehicles per

hour in the peak period to head west along Old Wallgrove Road and Archbold Road, rather than east along Old Wallgrove Road and Wallgrove Road. Plots of modelled traffic volumes from the revised strategic traffic modelling are provided in Attachment A.

Increase of the trip generation rate for the Ropes Creek Precinct to 21 trips per hectare results in an additional 1000 trips per hour in the 2-hour peak periods. Based on this additional trip generation, the

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strategic traffic modelling identified that the Archbold Road east facing ramps at the M4 would be required by 2021 to accommodate the forecast traffic demand.

2.3 Revised Micro Simulation Traffic Modelling

Following revision of the strategic traffic modelling, micro simulation traffic model demands were updated to reflect the inclusion of the Archbold Road east facing ramps at the M4 Motorway and the increased trip

generation rate for the Ropes Creek Precinct. This demand was used in the micro simulation traffic model to identify intersection capacity constraints and identify any queuing from Wallgrove Road onto the M7 and M4 Motorway. Under the 2031 scenario, the model assumed certain works such as road and

ramp widening and other associated works would be undertaken within the M7 Motorway corridor to maximise flow through the study area and to determine the localised works that would be required to serve the forecast traffic demand. These assumed works are broadly consistent with the Western

Sydney Employment Hub, Erskine Park Link Road Network Concept Plan, Environmental Assessment (RTA, 2008).

Further testing was also undertaken to determine the likely timeframe for M7 improvement works and

other links within the study area.

Testing of the 2021 design year and 2031 future horizon year showed the following:

Intersections along Wallgrove Road and Old Wallgrove Road perform acceptably for the 2021

forecast demand (including the Archbold Road east facing ramps with the M4 Motorway with and increased trip generation rate from 10 to 21 trips/hectare/2 hours for the Ropes Creek Precinct)

Under 2031 forecast demand scenario, it was identified that the southbound section of the M7

Motorways between the off-ramp from the M4 Motorway and the off-ramp to Wallgrove Road will be over capacity. Widening of this section to three lanes and widening of the Wallgrove Road off ramp to two lanes would be required to address this capacity constraint.

The intersection of Old Wallgrove Road and Wallgrove Road is likely to be over-capacity by 2031

and this will result in some queuing on the M7 and Wallgrove Road southbound in the morning peak period.

Localised widening of the M7 Motorway is likely to be required by 2026 as well as the construction of

the Southern Link Road network to relieve east-west traffic demand on Old Wallgrove Road.

2.4 SIDRA Intersection Modelling

The revised 2021 design year flows from the micro simulation traffic modelling were used in SIDRA intersection modelling to determine the operational performance of the following key intersections:

Old Wallgrove Road, Wallgrove Road and M7 southbound ramps;

Wallgrove Road, Mini Link Road and M7 northbound ramps; and

Old Wallgrove Road, Quarry Road and Mini Link Road.

These intersections were also tested under the 2031 future horizon year, however it is noted that these flows were capacity constrained in the morning peak period, indicating that the SIDRA modelling is

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underestimating delays at these intersections under the 2031 morning peak scenario. These intersections were modelled under the same geometric and operational arrangements as those identified in the REF. A summary of the intersection average delays and levels of service is shown in Table 1 for

the 2021 and 2031 scenarios.

SIDRA testing of key intersections within the study area showed that these intersections perform acceptably for the 2021 design year and that intersection performance is comparable to that reported in

the REF, with slightly better intersection performance in the evening peak period. Testing also showed that these intersections also performed acceptably under the 2031 future year horizon, however it should be noted that micro simulation modelling showed that the intersection of Wallgrove Road and Old

Wallgrove Road is at capacity in the morning peak period and that modelled flows used in the SIDRA modelling do not sufficiently reflect the forecast traffic demand through this intersection as modelled queues were observed extending onto the M7 Motorway. Consequently, the 2031 SIDRA modelling is

likely to be underestimating average delays at this intersection under the 2031 future year horizon.

Detailed outputs from the SIDRA modelling are presented in Attachment B.

Table 1 Summary of Intersection Performance

Intersection Morning Peak Evening Peak

Av Delay (s)

LoS DoS Av Delay (s)

LoS DoS

2021 Design Year

Old Wallgrove Rd/Wallgrove Rd 41.5 C 1.00 23.6 B 0.74

Wallgrove Rd/Mini Link Rd 51.9 D 1.00 42.7 D 0.80

Old Wallgrove Rd/Quarry Rd 38.5 C 0.70 37.2 C 0.80

2031 Future Horizon Year

Old Wallgrove Rd/Wallgrove Rd* 46.5 D 1.02 25.8 B 0.90

Wallgrove Rd/Mini Link Rd 44.4 D 0.90 45.0 D 0.87

Old Wallgrove Rd/Quarry Rd 35.1 C 0.60 37.4 C 0.68

*Denotes traffic demand that is underestimated due to capacity constraint

2.5 Summary

Revised traffic modelling undertaken to include the increased traffic generation rate for Ropes Creek and Archbold Road east-facing ramps to the M4 Motorway showed that the increased traffic generation in

Ropes Creek could be accommodated under the proposed concept design. This assumes that the Archbold Road east-facing ramps with the M4 Motorway and the southern link road connection to The Horsley Drive are constructed by 2021.

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The proposed localised widening of the M7 Motorway that would be required for the 2031 future horizon year (additional lanes in the southbound direction between the M4 Motorway and Old Wallgrove Road and widening of off-ramps to and from Old Wallgrove Road) are broadly consistent with the widening identified in the Western Sydney Employment Hub, Erskine Park Link Road Network Concept Plan, Environmental Assessment (RTA, 2008).

This document recommends an additional northbound lane on the M7 Motorway and this difference is

likely due to different assumptions in the connectivity of the Southern Link Road which was previously assumed to be connected directly to a new interchange at the M7 Motorway rather than to the Horsley Drive, as assumed in the current modelling.

3 Response to REF Submissions

Specific comments raised by stakeholders during the display of the REF are provided below, along with specific responses that address these comments.

3.1 Blacktown City Council

3.1.1 Item 1 (c) There is an inconsistency noted in the trip generation used in the GHD traffic study (2012) for Ropes Creek Precinct and Erskine Park Employment Area. 10 trips per hectare for the two hour

peak period were used for both Ropes Creek and Erskine Park Employment Area whereas 21 trips per hectare for two hour peak period were used for Eastern Creek Precinct and Lands south of Sydney Water Pipeline.

…Council questions the validity of the assessment as the reduced trip generation rates were opposed in the past by Council during the traffic modelling of Erskine Park Link Road in 2009. It is unclear whether the intersections would perform to the satisfactory levels if 21 trips per hectare for

two-hour peak were used for all precincts within the entire WSEA.

Erskine Park Employment Area trip generation has been agreed with Penrith Council at 10 trips per hectare for the two hour peak period. A sensitivity test has been undertaken using a revised trip rate of

21 trips per hectare for the Ropes Creek Precinct, which falls within the Blacktown LGA. The details of this sensitivity test are documented in Section 2 of this letter.

Sensitivity testing shows that the proposed concept design has sufficient capacity to serve increased

traffic demand associated with a higher trip generation rate for Ropes Creek for the 2021 design year, provided that Archbold Road is extended to meet with the M4 Motorway with east facing ramps with on the motorway by 2021.

3.2 Westlink M7

3.2.1 Item 1.1 Whilst the GHD Traffic and Transport Report contains modelling of the M7-off ramp impacts, no detailed modelling has been provided as to the performance of the on-ramps and how any on-

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ramp deficiencies might be addressed (e.g. lane widening, ramp metering). There does not appear to have been any detailed consideration given to the immediate impact of the widening of Wallgrove Road will have on the M7 Motorway and the interface issues that will arise in relation to

such works. What interface arrangements are proposed by RMS to address these risks?

Traffic modelling undertaken by GHD has taken into consideration the interface of the M7 on and off ramps at Wallgrove Road at the micro simulation stage.

This further traffic modelling that includes additional trip generation from the Ropes Creek Precinct from 10 to 21 trips/hectare/ 2 hours and the inclusion of the Archbold Road east-facing ramps with the M4 Motorway have shown that no additional widening works within the M7 Motorway are required for the

2021 design year.

Further modelling of the 2031 future horizon year shows that the following localised improvements would be required between 2021 and 2026:

Construction of the Southern Link Road

Widening of the M7 southbound between the M4 and Old Wallgrove Road to four lanes; and

Widening of the existing southbound-off ramp to Old Wallgrove Road to two lanes.

The traffic modelling also identified that the intersection of Old Wallgrove Road and Wallgrove Road is likely to be over-capacity in the morning peak period by 2026 and that queues form this intersection are

likely to extend back to the M7 Motorway. Further work will be required to determine the works that will be required to address this queuing onto the M7 Motorway from Wallgrove Road. Further details of traffic modelling are provided in Section 2 of this letter.

3.2.2 Item 1.2 It is noted that there is a modelling error in the report. The 2021 Wallgrove Road/Mini Link

Road/M7 model shows that the M7 ramp incorrectly operating as “Level of Service A” even though its’ constituent movements operate at Levels of Service C,D and F. The SIDRA model summary shows a NaN error code which is considered very serious by SIDRA Solutions who have

commented that they “would be very hesitant to make use of these results without establishing the cause of this problem”.

SIDRA solutions have been contacted regarding the source of this problem and have confirmed that the

NaN code and the resulting Level of Service measurement for the abovementioned approach are a display error relating to an older version of the software. The response from SIDRA Solutions is contained in Attachemnt C:

Revised model outputs provided by SIDRA Solutions showed that the model outputs produced by the newer software version are consistent with those provided in the report. These revised SIDRA results are also provided in Attachment C.

Item 1.3 WSO Co’s review of the EMME modelling (as summarised in the GHD Traffic and Transport report) suggests that road capacity constraints are already being reached both northbound and

southbound on the M7 between M4 and Old Wallgrove Road. The Paramics modelling also

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suggests deficiencies at the M7 northbound on and off ramps at Wallgrove Road in the future, with the 2021 model suggesting that flows onto the M7 from Wallgrove Road may reach their capacity in 2021; which will result in queues on the M7 northbound ramps. In addition, the report does not

model the current a future queuing issues at the M4 entry/exit points or the Horsley Drive intersection.

The revised traffic modelling with the Archbold Road east facing ramps at the M4 Motorway shows that

there is unlikely to be queuing from Wallgrove Road onto the M7 Motorway in the peak periods for the 2021 design year. By 2031, with localised widening of the M7 Motorway in place, the intersection of Wallgrove Road and Old Wallgrove Road is likely to be over capacity in the morning peak period and this

will lead to queuing onto the M7 Motorway. Interim year testing showed that this is likely to occur before 2026.

Modelling undertaken for the REF did include ramps from the M4 to the M7 but did not include the

Horsley Drive Interchange, as this interchange is not considered to be within the scope of works of this study. Further modelling of this section of the M7 has been undertaken by AECOM on behalf of DoP&I and is documented in Southern Link Road Transport Assessment (2011). This document identified that

Horsley Drive interchange was likely to be a key constraint for the M7 and recommended widening of The Horsley Drive to provide an additional 2 eastbound lanes in the vicinity of the existing interchange.

3.2.3 Item 1.5 The GHD Traffic and Transport Report does not consider in detail the impact that the creation of merge conflicts or the potential compromising of safety resulting from the changed “traffic flows and routes” will have. No consideration has been given to long term impacts on the M7 Motorway

such as congestion, loss of traffic on the M7 Motorway and the instances of trip reductions due to the Wallgrove Road Upgrade and how these impacts will be mitigated.

The micro simulation modelling has taken into account the impacts of merging on traffic flows on the M7

in the immediate local area of Old Wallgrove Road. The micro simulation modelling has identified that there are unlikely to be substantial impacts on the capacity of the M7 Motorway between the M4 Motorway and Old Wallgrove Road as a result of the proposal for the 2021 design year traffic demand.

Merge impacts are expected by 2026, particularly in the southbound direction in the morning peak period, where the traffic from the M4 Motorway to the M7 Motorway is likely to conflict with traffic leaving the M7 Motorway to join Old Wallgrove Road. Widening of this section and the off-ramp to Old Wallgrove

Road will mitigate this. However, queuing onto the M7 Motorway is still likely as this widening will not increase the capacity of the Old Wallgrove Road and Wallgrove Road intersection, which is likely to be over capacity by 2031.

It should be noted that the localised widening of Wallgrove Road in the vicinity of Wallgrove Road in the concept design is intended to respond to increased need for accessibility to the Western Sydney Employment Area and not as a cross-regional route that is intended to provide an alternative to the M7

Motorway. Localised widening of Wallgrove Road is unlikely to make Wallgrove Road comparable in speed or congestion to the M7 and it is very unlikely that traffic will divert from the M7 Motorway to use Wallgrove Road for any substantial distance. Analysis of strategic model traffic volumes shows that

8 21/22191/188178

further development within the WSEA will result in more traffic using the M7 Motorway, especially during peak periods.

4 Conclusions

GHD have undertaken further traffic modelling of Old Wallgrove Road upgrade to address comments

submitted to RMS during public display of the REF. This additional modelling examined the following issues:

Increase in traffic generation assumptions for the Ropes Creek Precinct from 10 to 21 trips per

hectare for a two-hour peak period;

Extension of Archbold Road with east facing ramps at the M4 Motorway;

Revision of the traffic demand distribution in the study area based on updated cordon matrices;

Widening requirements for the M7 Motorway between the 2021 design year and the 2031 future

horizon year.

Based on this additional modelling, it has been concluded that the concept design as part of the REF has sufficient capacity to serve the forecast 2021 design year traffic demand under a higher trip generation assumption for the Ropes Creek Precinct, provided that Archbold Road is extended with east facing

ramps at the M4 Motorway.

Furthermore, for the 2026 and 2031 future horizon years showed that localised widening on the M7 Motorway in the southbound direction as well as widening of the southbound off ramp to Wallgrove Road

would be required by 2026 to relieve traffic congestion on the M7 Motorway, and that the Southern Link Road would need to be constructed to reduce traffic demand on Old Wallgrove Road. Under the 2031 future horizon year scenario, the intersection of Wallgrove Road and Old Wallgrove Road is likely to be

operating over capacity and is expected to result on some queuing in the southbound direction on the M7 Motorway in the morning peak.

Sincerely

Iwan Smith Team Leader, Transport Modelling

0292397405

9 21/22191/188178

Attachment A – Strategic Model Outputs

342-48

589-247

1253

589

19671310

1967389

14752357

218

17352574

27

27

231

-27 54

134

-27

134

-27

134

45

134

4545

134

-354

45-2

2045

-220

121

-220

315

541-537

4

63

-714

-714

97121

97

97

121

121

121

72

54

54

165

-46540

-287

-48

111

-465

-465721

3

-75

-75-75

194

194

-75

-761

-285-340

-285

-340

-285-340

220

-939

-187-379

-68

11-1

8711-1

07

-52

262

-107

194

262

-425-767

86

355

-500-210

-471

-33

-177

-529

45

-908

-1393

-385

-229

-1262

-1417

-120

-109

-1093

-495

-1094

-785

-148

-69

-348 -45

-87

158

-87

158

158

-47

-103

-48

-628

92

-979

161

-385

-118

-166

84

-164

-29

74

-106

-53

-97

-757

-348

-757

-55

-160

676

-54

-55

-54

-65

-499

294

59

85

-65

85-1

07

32

152

-77-22

-56

32-62

115

160

174

-36

-18

44

-36

-304

44

-40-530

-353

91-2

64

-456

91

93

-264-458

93

-211

-52-316

-211

-481-1094

20

-481

-986

-986

-499

-668

-188-652

2

294

676

-37

15

2611

444

3674

1787

PM Peak 2021 Traffic Volume Difference Plot (pcu)(1 - 2)

1. With Archbold Road Link roads, Ropes Creek Trip Generation of 10 per hectare (sc2152 )1. No Archbold Road Link roads, Ropes Creek Trip Generation of 10 per hectare (sc92161 )

117-49

-42

159

175

-42 242

-13

242-185

37

57 -7

136

50

0

18

18

67

18

-0

7418

7418

74-3

1

74-3

1

74-3

1

7413

3-3

1

207

-31

207

-0

207

129

54

9

-1

-68

-68

-7-0

-7

-7

-0

-0

-0

-49

-0

-0

51

5182

159

-49

5182

828228

4

-31

-31-31

129

129

-31

201

14

55

551455

145514

13172

43

2818

7215

-1

65

18765

196

4

5919

6

129

59

137

228

85

100

8210

8210

289

81

75

158

371

81

154

5

19

492

219

-65

378

-2

220 -2

3

45

3

457

457

7

43

7

43

10

-15

75

-97

152

2

67-65

-67

0

445

220

445

6

323

91

4

64

424

144

103

229

50

424

50

440

2

52

535

15

113

-212

34

153

167

0

37

15

0

72

15

1561

-1

-615

0

20

-6

158

0

150149

0

20

4

44

20

114-65

33

114

85

85

144

220

539

-157

103

91

675

50

111

485

111


1. With Archbold Road Link roads, Ropes Creek Trip Generation of 21 per hectare (sc2151 )1. With Archbold Road Link roads, Ropes Creek Trip Generation of 10 per hectare (sc2152 )

459-97

547-88

1428

547

22101297

2210

204

1512 2414

211

17712625

45

45

298

-9

54

208

-920

8-9

208

14

208

14

1420

8-2

2114

-13

14-1

3

120

-13

444

547-534

13

62

-782

-782

90120

90

90

120

120

120

23

54

54

216

-38340

-128

-97

162

-383

-383749

3

-106

-106

324

324

-106

-560

-271-285

-271

-285

-271-285

233

-767

-1-164

-1

-69

76-176

89

-48

321

89

324

321

-288-538 455

-418-200

-388

-33

-167

-447

45

-619

-1312

-310

-72

-891

-1263

-115

-91

-601

-276

-1159

-406

-149

-69

-129-47

-84

203

-84

203203

-40

-8-8-103

-48

-610

92

-969

146

-310

-215

-14

86-96

-29

9

-106

-119

-97

-311

-129

-311

-49

163

767

-51

-49

-51

359

-355

398288

135

359

135

333

33

203

-62-21

-43

31-50

148

313

341

-36

19

59

-36

-231

59

116-529

-354

86-1

15

-436

86

-72

93

-115-309

93

-191

-48-312

-191

-367-1159

53

-367

-901

-901

-355

-448

351 -809

2

398

767

-37

690

2661

555

4159

1899



952-131

2021 -1069

42

2021

4482481

448333

2638781 331

2680 1112

406 -3

65

406

51

288118

-46

288

-46

288

-46

392

-46

392

392

-46

2939

2

-17

392

-17

329

-17

34

12657

183

50

-406

-406

42289

42

97

289

289

289

104

118

118

157

39 -10

-756

-186

55

55

55

39-1

0

-10

460

2532

63

6363

-295

-295

6363

-143

-600-309

-600

-309

-600-309

-190-639

-128

0

-200

184

-128

0

-38

-687

-511

4

158

-68715

8

273-579 829

-199-465

-171

-32

-431

-310

94

-647

-1493

-463

17

-1047

-1260

-91

-202

-907

-933

-490

-299

-278

-47-770 -58

149

42

149

4242

77-61

-120

-641

44

-1008

56

-463

-82

134

-28-17

-100

-75

-28

-148

-136

-256

-770

-256

-59

-86

195

-54

-59

-54

34

-694

763

15

362

34 362

37

-114

231

19-204

-23

-200-79

-19

23

-6

-47

-135

-16

-47

-118

-16

-153-265

-485

48-1

24

-347

48

17

64

-12421

64

-118

-511

-724

-118

-770-490

119

-770

-498

-498

-694

-515

-145 -1086

8

763

195

-38

59

1200

1797

3464

AM Peak 2021 Traffic Volume Difference Plot (pcu)(1 - 2)


21957

15366

55

15355

-22 55-7

9

48 14

09

62

1

70

70

19

68

2

1868

1868

1813

7

18

137

1813

7

1830

137

4813

7

48

0

48

12

-2114

112

-6-1

-0

-0

113

1

1

13

13

13

70

2

2

31

29 1

66

57

29 1

11-175

50

137137137

12 12

12

12

137

50

54

20

20

54205420

54255325

-3

266-3

-81

266-84

163

86

-101

163

12

-101

124

300

8

994

9

94

69

26

26

468

28

1

5858

484

3

43

99

368

116

108

-126

-0497

26

12

26

1247

1247

47

13

7

13

169

126

28

-1

3129

2

131

1

4

110

497

110

2

539

182

6

26

159

146

39

676

457

159

457

159

38

496

156

139

1

391

195

33

37

46

152

-1

46

22

-1

41

-45

-481

0

-4

1

0

81-0

0

0

0

8686

0

-8

116

153

-8

150

150

146

26

290292

39

182

229

61

483

106

494


1. With Archbold Road Link roads, Ropes Creek Trip Generation of 21 per hectare (sc2101 )1. With Archbold Road Link roads, Ropes Creek Trip Generation of 10 per hectare (sc2102 )

1172-74

2174 -1002

96

2174

5022459

502326

2647829 345

2689 1174

476 -3

44

476

70

356120

-28

356

-28

356

-28

529

-28

529

529

-28

5952

9

3152

9

31

329

31

46

124171

295

44

-406

-406

43302

43

98

302

302

302

173

120

120

188

68 -9

-690

-129

55

55

55

68 -9

-9-9

285

25

200

200200

-283

-283

200

-93

-546-290

-546

-290

-546-290

-137-613

98

-101

4

-203

103

-101

4

-122

-525

-426

4

57-5

2557

397-279 838

-189-371

-161

-32

-337

-300

94

-620

-1025

-435

18

-989

-776

-87

-159

-808

-565

-373

-192

-404

-48

-272-58

175

54

175

5454

1919-61

-120

-445

44

-840

182

-435

-83

136

102-16

-100

57

-28

-147

-132

-146

-272

-146

-57453

377

-48

-57

-48

193

-548

802691

819

193

819

196

-76

727

20-165

-22

-160-77

176

56

31

-1

17

-17

-1

-96

-17

-112-269

-479

44-4

4

-347

44

18

64

-4421

64

-118

-426

-638

-118

-778-373

272

-778

-348

-348

-548

-489

146-794

8

802

377

-38

288

1261

1903

3958



10 21/22191/188178

Attachment B – Revised SIDRA Outputs (Ropes Creek Sensitivity Test)

LANE SUMMARY Site: 2021 AM

Wallgrove Rd, Mini Link Rd and M7 Ramp

Signals - Fixed Time Cycle Time = 120 seconds (User-Given Cycle Time)

Lane Use and PerformanceDemand Flows 95% Back of Queue

HV Cap.Deg.Satn

LaneUtil.

AverageDelay

Level ofService

Lane Length

SL Type

Cap.Adj.

Prob. Block.L T R Total Vehicles Distance

veh/h veh/h veh/h veh/h % veh/h v/c % sec veh m m % %South: Wallgrove Rd South

Lane 1 589 0 0 589 14.0 5891

1.0003

100 37.68

LOS C8

21.98

171.48

105 Turn Bay 0.0 50.0

Lane 2 230

203 0 226 14.0 509 0.445 100 38.0 LOS C 9.9 77.9 220 – 0.0 0.0

Lane 3 0 228 0 228 14.0 512 0.445 100 38.0 LOS C 10.0 78.3 220 – 0.0 0.0

Lane 4 0 0 169 169 14.0 256 0.659 100 55.3 LOS D 9.2 71.8 170 Turn Bay 0.0 0.0


Approach 612 431 337 1380 14.0 1.000 42.1 LOS C 21.9 171.4

East: M7 Off/Onload ramp

Lane 1 20 105 0 125 14.0 1251

1.0003

100 48.48

LOS D8

6.28

49.08

30 Turn Bay 0.0 50.0

Lane 2 0 376 0 376 14.0 376 1.0003

100 94.78

LOS F8

31.28

244.88

150 Turn Bay 0.0 50.0

Lane 3 0 0 171 171 14.0 2311

0.743 100 43.8 LOS D 7.7 60.4 50 Turn Bay 0.0 22.1

Lane 4 0 0 296 296 14.0 398 0.743 100 45.9 LOS D 15.3 120.1 365 – 0.0 0.0

Approach 20 481 467 968 14.0 1.000 64.8 LOS E 31.2 244.8

North: Wallgrove Rd North

Lane 1 35 377 0 412 14.0 515 0.801 100 42.3 LOS C 21.1 165.1 200 – 0.0 0.0

Lane 2 0 410 0 410 14.0 512 0.801 100 33.6 LOS C 21.1 165.6 200 – 0.0 0.0

Lane 3 0 410 0 410 14.0 512 0.801 100 33.6 LOS C 21.1 165.6 200 – 0.0 0.0

Lane 4 0 0 242 242 14.0 256 0.944 100 86.5 LOS F 17.8 139.3 115 Turn Bay 0.0 22.4

Lane 5 0 0 242 242 14.0 256 0.944 100 64.98

LOS E8

14.68

114.28

70 Turn Bay 0.0 50.0

Approach 35 1197 483 1715 14.0 0.944 47.5 LOS D 21.1 165.6

West: Mini Link Rd

Lane 1 46 24 0 70 4.8 304 0.231 406

52.6 LOS D 3.6 26.3 350 – 0.0 0.0

Lane 2 0 138 0 138 14.0 241 0.573 100 54.1 LOS D 7.8 61.2 350 – 0.0 0.0

Lane 3 0 0 223 223 14.0 270 0.824 100 67.7 LOS E 13.9 109.1 125 Turn Bay 0.0 0.0


Approach 46 162 445 653 13.0 0.824 63.2 LOS E 13.9 109.1

Intersection 4735 13.8 1.000 51.4 LOS D 31.2 244.8

Level of Service (LOS) Method: Delay (RTA NSW). Lane LOS values are based on average delay per lane.Intersection and Approach LOS values are based on average delay for all lanes.SIDRA Standard Delay Model used.

0 Excess flow from back of an adjacent short lane1 Reduced capacity due to a short lane effect3 x = 1.00 due to short lane.6 Lane underutilisation due to downstream effects8 Delay, queue length and stops for the short lane have been cut down to fit in the queuing space. You may wish to change the short lane to

a full lane to investigate the effect on the adjacent lane performance.

Processed: Tuesday, 26 March 2013 5:55:31 PMSIDRA INTERSECTION 5.1.13.2093

Copyright © 2000-2011 Akcelik and Associates Pty Ltdwww.sidrasolutions.com

Project: G:\21\22191\Tech\Supp Report SIDRA\WR_MiniLink.sip8000065, GHD SERVICES PTY LTD, ENTERPRISE

LANE SUMMARY Site: 2021 PM

Wallgrove Rd, Mini Link Rd and M7 RampSignals - Fixed Time Cycle Time = 120 seconds (User-Given Cycle Time)


HV Cap.Deg.Satn

LaneUtil.

AverageDelay

Level ofService

Lane Length

SL Type

Cap.Adj.



Lane 1 459 0 0 459 14.0 1237 P 100 10.3 LOS A 2.0 15.9 105 Turn Bay 0.0 0.0

Lane 2 0 455 0 455 14.0 572 P 100 41.4 LOS C 24.1 188.7 220 – 0.0 0.0

Lane 3 0 455 0 455 14.0 572 P 100 41.4 LOS C 24.1 188.7 220 – 0.0 0.0

Lane 4 0 0 291 291 14.0 412 P 100 44.0 LOS D 14.4 113.3 170 Turn Bay 0.0 0.0


Approach 459 909 581 1949 14.0 0.795 34.9 LOS C 24.1 188.7


Lane 1 2 56 0 58 14.0 91 P 100 65.3 LOS E 3.6 28.3 30 Turn Bay 0.0 0.0



Lane 4 0 0 109 109 14.0 142 P 100 66.9 LOS E 6.6 51.6 365 – 0.0 0.0

Approach 2 113 217 332 14.0 0.763 66.4 LOS E 6.6 51.6


Lane 1 25 173 0 198 14.0 278 P 100 61.3 LOS E 11.2 87.8 200 – 0.0 0.0

Lane 2 0 193 0 193 14.0 271 P 100 48.0 LOS D 10.7 83.8 200 – 0.0 0.0

Lane 3 0 193 0 193 14.0 271 P 100 48.0 LOS D 10.7 83.8 200 – 0.0 0.0

Lane 4 0 0 93 93 14.0 128 P 100 71.9 LOS F 5.8 45.1 115 Turn Bay 0.0 0.0


Approach 25 558 185 768 14.0 0.723 57.2 LOS E 11.2 87.8

West: Mini Link Rd

Lane 1 51 140 0 191 10.3 604 P 406

34.1 LOS C 8.3 63.1 350 – 0.0 0.0

Lane 2 0 460 0 460 14.0 587 P 100 41.7 LOS C 25.3 198.7 350 – 0.0 0.0

Lane 3 0 0 309 309 14.0 4931

P 100 40.4 LOS C 14.1 110.9 125 Turn Bay 0.0 0.0

Lane 4 0 0 272 272 14.0 4351

P 100 39.5 LOS C 12.1 95.2 105 Turn Bay 0.0 0.0

Approach 51 600 581 1232 13.4 0.784 39.7 LOS C 25.3 198.7


P: You need to Process this Site (F9) for this variable to be computed.


1 Reduced capacity due to a short lane effect6 Lane underutilisation due to downstream effects

Processed: Wednesday, 20 February 2013 5:06:53 PMSIDRA INTERSECTION 5.1.2.1953




Wallgrove Rd, Mini Link Rd and M7 Ramp



HV Cap.Deg.Satn

LaneUtil.

AverageDelay

Level ofService

Lane Length

SL Type

Cap.Adj.



Lane 1 412 0 0 412 14.0 5741

0.718 100 29.7 LOS C 13.7 107.7 105 Turn Bay 0.0 7.3

Lane 2 0 241 0 241 14.0 617 0.390 100 30.6 LOS C 9.3 72.8 220 – 0.0 0.0

Lane 3 0 241 0 241 14.0 617 0.390 100 30.6 LOS C 9.3 72.8 220 – 0.0 0.0



Approach 412 481 288 1181 14.0 0.718 35.7 LOS C 13.7 107.7


Lane 1 15 102 0 117 14.0 1301

0.904 100 51.18

LOS D8

6.28

49.08

30 Turn Bay 0.0 50.0


Lane 3 0 0 154 154 14.0 2101

0.734 100 49.2 LOS D 7.6 59.2 50 Turn Bay 0.0 20.3

Lane 4 0 0 240 240 14.0 327 0.734 100 51.0 LOS D 12.9 101.4 365 – 0.0 0.0

Approach 15 483 394 892 14.0 0.904 55.9 LOS D 25.8 202.6


Lane 1 35 459 0 494 14.0 619 0.799 100 37.5 LOS C 26.3 206.3 200 – 0.0 7.8

Lane 2 0 493 0 493 14.0 617 0.799 100 26.6 LOS B 23.4 183.6 200 – 0.0 0.0

Lane 3 0 493 0 493 14.0 617 0.799 100 26.6 LOS B 23.4 183.6 200 – 0.0 0.0


Lane 5 0 0 210 210 14.0 2461

0.855 100 70.2 LOS E 13.4 105.2 70 Turn Bay 0.0 42.3

Approach 35 1445 441 1921 14.0 0.855 39.4 LOS C 26.3 206.3

West: Mini Link Rd

Lane 1 55 27 0 82 4.6 263 0.310 406

56.3 LOS D 4.4 31.8 350 – 0.0 0.0

Lane 2 0 150 0 150 14.0 196 0.769 100 61.2 LOS E 9.3 72.6 350 – 0.0 0.0



Approach 55 177 188 420 12.2 0.827 67.0 LOS E 9.3 72.6



1 Reduced capacity due to a short lane effect6 Lane underutilisation due to downstream effects8 Delay, queue length and stops for the short lane have been cut down to fit in the queuing space. You may wish to change the short lane to


Processed: Thursday, 21 February 2013 8:51:32 AMSIDRA INTERSECTION 5.1.2.1953




Wallgrove Rd, Mini Link Rd and M7 RampSignals - Fixed Time Cycle Time = 120 seconds (User-Given Cycle Time)


HV Cap.Deg.Satn

LaneUtil.

AverageDelay

Level ofService

Lane Length

SL Type

Cap.Adj.



Lane 1 132 0 0 132 14.0 9941

0.133 100 13.2 LOS A 1.3 10.3 105 Turn Bay 0.0 0.0

Lane 2 0 449 0 449 14.0 707 0.634 100 28.6 LOS C 18.7 146.5 220 – 0.0 0.0

Lane 3 0 449 0 449 14.0 707 0.634 100 28.6 LOS C 18.7 146.5 220 – 0.0 0.0

Lane 4 0 0 454 454 14.0 526 0.863 100 42.5 LOS C 25.1 196.4 170 Turn Bay 0.0 18.1


Approach 132 897 908 1937 14.0 0.863 34.1 LOS C 25.1 196.4


Lane 1 2 16 0 18 14.0 1201

0.150 100 45.5 LOS D 0.9 6.9 30 Turn Bay 0.0 0.0



Lane 4 0 0 98 98 14.0 114 0.857 100 72.0 LOS F 6.2 48.7 365 – 0.0 0.0

Approach 2 61 195 258 14.0 0.857 65.7 LOS E 6.2 48.7


Lane 1 32 182 0 214 14.0 249 0.859 100 71.3 LOS F 14.0 110.0 200 – 0.0 0.0

Lane 2 0 207 0 207 14.0 241 0.859 100 54.8 LOS D 12.6 99.0 200 – 0.0 0.0

Lane 3 0 207 0 207 14.0 241 0.859 100 54.8 LOS D 12.6 99.0 200 – 0.0 0.0



Approach 32 596 38 666 14.0 0.859 61.0 LOS E 14.0 110.0

West: Mini Link Rd

Lane 1 51 139 0 190 10.2 543 0.351 406

37.5 LOS C 8.7 66.3 350 – 0.0 0.0

Lane 2 0 458 0 458 14.0 527 0.869 100 52.9 LOS D 28.9 226.2 350 – 0.0 0.0



Approach 51 597 302 950 13.2 0.869 50.5 LOS D 28.9 226.2



1 Reduced capacity due to a short lane effect6 Lane underutilisation due to downstream effects





Wallgrove Road & Old Wallgrove Road



HV Cap.Deg.Satn

LaneUtil.

AverageDelay

Level ofService

Lane Length

SL Type

Cap.Adj.



Lane 1 150 0 0 150 14.0 4801

P 100 10.1 LOS A 0.5 4.1 55 Turn Bay 0.0 0.0

Lane 2 0 266 0 266 14.0 436 P 100 35.8 LOS C 12.4 97.4 200 – 0.0 0.0

Lane 3 0 266 0 266 14.0 436 P 100 35.8 LOS C 12.4 97.4 200 – 0.0 0.0

Lane 4 0 266 0 266 14.0 436 P 100 35.8 LOS C 12.4 97.4 200 – 0.0 0.0


Approach 150 797 5 952 14.0 0.609 31.9 LOS C 12.4 97.4

East: M7 Access (East)

Lane 1 377 0 0 377 14.0 3771

P 100 37.78

LOS C8

13.58

106.18

65 Turn Bay 0.0 50.0

Lane 2 2320

242 0 474 14.0 731 P 100 28.1 LOS B 20.6 161.3 300 Turn Bay 0.0 0.0

Lane 3 0 487 0 487 14.0 752 P 100 26.2 LOS B 19.7 154.4 720 – 0.0 0.0

Lane 4 0 0 53 53 14.0 1291

P 100 62.9 LOS E 2.9 22.5 35 Turn Bay 0.0 0.0

Approach 609 729 53 1391 14.0 1.000 31.4 LOS C 20.6 161.3


Lane 1 315 382 0 697 14.0 699 P 100 61.5 LOS E 54.7 429.0 480 – 0.0 0.0

Lane 2 0 690 0 690 14.0 692 P 100 58.9 LOS E 54.0 423.0 480 – 0.0 0.0



Approach 315 1072 367 1754 14.0 0.997 57.9 LOS E 54.7 429.0

West: Old Wallgrove Rd West

Lane 1 158 0 0 158 14.0 1105 P 100 10.8 LOS A 2.1 16.5 305 – 0.0 0.0

Lane 2 0 84 0 84 14.0 466 P 100 37.2 LOS C 3.8 29.8 305 – 0.0 0.0

Lane 3 0 84 0 84 14.0 466 P 100 37.2 LOS C 3.8 29.8 305 – 0.0 0.0

Approach 158 167 0 325 14.0 0.179 24.4 LOS B 3.8 29.8

Intersection 4422 14.0 1.000 41.5 LOS C 54.7 429.0



0 Excess flow from back of an adjacent short lane1 Reduced capacity due to a short lane effect8 Delay, queue length and stops for the short lane have been cut down to fit in the queuing space. You may wish to change the short lane to




Project: G:\21\22191\Tech\Supp Report SIDRA\OWR_WR.sip8000065, GHD SERVICES PTY LTD, ENTERPRISE


Wallgrove Road & Old Wallgrove Road Signals - Fixed Time Cycle Time = 105 seconds (Optimum Cycle Time - Minimum Delay)


HV Cap.Deg.Satn

LaneUtil.

AverageDelay

Level ofService

Lane Length

SL Type

Cap.Adj.



Lane 1 148 0 0 148 14.0 8111

P 100 9.4 LOS A 0.3 2.6 55 Turn Bay 0.0 0.0

Lane 2 0 340 0 340 14.0 602 P 100 21.9 LOS B 11.3 88.7 200 – 0.0 0.0

Lane 3 0 340 0 340 14.0 602 P 100 21.9 LOS B 11.3 88.7 200 – 0.0 0.0

Lane 4 0 340 0 340 14.0 602 P 100 21.9 LOS B 11.3 88.7 200 – 0.0 0.0


Approach 148 1019 11 1178 14.0 0.564 20.7 LOS B 11.3 88.7


Lane 1 310 0 0 310 14.0 4221

P 100 28.9 LOS C 10.1 78.9 65 Turn Bay 0.0 22.6

Lane 2 0 184 0 184 14.0 740 P 100 19.3 LOS B 4.9 38.6 300 Turn Bay 0.0 0.0

Lane 3 0 184 0 184 14.0 740 P 100 19.3 LOS B 4.9 38.6 720 – 0.0 0.0


Approach 310 368 3 681 14.0 0.735 23.8 LOS B 10.1 78.9


Lane 1 601 0 0 601 14.0 812 P 100 19.0 LOS B 15.4 120.4 480 – 0.0 0.0

Lane 2 0 453 0 453 14.0 654 P 945

20.3 LOS B 15.9 124.5 480 – 0.0 0.0



Approach 601 453 157 1211 14.0 0.740 24.6 LOS B 15.9 124.5


Lane 1 458 0 0 458 14.0 1048 P 100 11.7 LOS A 8.6 67.1 305 – 0.0 0.0

Lane 2 0 340 0 340 14.0 533 P 100 34.9 LOS C 15.3 119.6 305 – 0.0 0.0

Lane 3 0 340 0 340 14.0 533 P 100 34.9 LOS C 15.3 119.6 305 – 0.0 0.0

Approach 458 680 0 1138 14.0 0.638 25.6 LOS B 15.3 119.6

Intersection 4208 14.0 0.740 23.6 LOS B 15.9 124.5



1 Reduced capacity due to a short lane effect5 Lane underutilisation determined by program





Wallgrove Road & Old Wallgrove Road



HV Cap.Deg.Satn

LaneUtil.

AverageDelay

Level ofService

Lane Length

SL Type

Cap.Adj.



Lane 1 101 0 0 101 14.0 5141

0.197 100 10.1 LOS A 0.3 2.5 55 Turn Bay 0.0 0.0

Lane 2 0 278 0 278 14.0 451 0.616 100 34.8 LOS C 12.9 101.0 200 – 0.0 0.0

Lane 3 0 278 0 278 14.0 451 0.616 100 34.8 LOS C 12.9 101.0 200 – 0.0 0.0

Lane 4 0 278 0 278 14.0 451 0.616 100 34.8 LOS C 12.9 101.0 200 – 0.0 0.0


Approach 101 834 5 940 14.0 0.616 32.4 LOS C 12.9 101.0


Lane 1 357 0 0 357 14.0 3571

1.0003

100 39.78

LOS C8

13.58

106.18

65 Turn Bay 0.0 50.0

Lane 2 2770

141 0 418 14.0 666 0.627 100 31.3 LOS C 19.0 149.3 300 Turn Bay 0.0 0.0

Lane 3 0 399 330

432 14.0 689 0.627 100 29.4 LOS C 18.1 142.2 720 – 0.0 0.0

Lane 4 0 0 128 128 14.0 128 1.0003

100 71.88

LOS F8

8.08

62.78

35 Turn Bay 0.0 58.8

Approach 634 540 161 1335 14.0 1.000 36.8 LOS C 19.0 149.3


Lane 1 277 491 0 768 14.0 754 1.019 100 70.0 LOS E 64.8 507.8 480 – 0.0 10.1

Lane 2 0 766 0 766 14.0 752 1.019 100 68.1 LOS E 64.3 504.3 480 – 0.0 9.5



Approach 277 1257 568 2102 14.0 1.019 63.8 LOS E 64.8 507.8


Lane 1 281 0 0 281 14.0 1078 0.261 100 12.9 LOS A 5.6 43.8 305 – 0.0 0.0

Lane 2 0 41 0 41 14.0 466 0.088 100 36.1 LOS C 1.8 14.2 305 – 0.0 0.0

Lane 3 0 41 0 41 14.0 466 0.088 100 36.1 LOS C 1.8 14.2 305 – 0.0 0.0

Approach 281 82 0 363 14.0 0.261 18.1 LOS B 5.6 43.8



0 Excess flow from back of an adjacent short lane1 Reduced capacity due to a short lane effect3 x = 1.00 due to short lane.8 Delay, queue length and stops for the short lane have been cut down to fit in the queuing space. You may wish to change the short lane to






Wallgrove Road & Old Wallgrove Road Signals - Fixed Time Cycle Time = 100 seconds (Optimum Cycle Time - Minimum Delay)


HV Cap.Deg.Satn

LaneUtil.

AverageDelay

Level ofService

Lane Length

SL Type

Cap.Adj.



Lane 1 76 0 0 76 14.0 7121

0.107 100 9.5 LOS A 0.2 1.3 55 Turn Bay 0.0 0.0

Lane 2 0 355 0 355 14.0 506 0.702 100 27.5 LOS B 14.0 109.7 200 – 0.0 0.0

Lane 3 0 355 0 355 14.0 506 0.702 100 27.5 LOS B 14.0 109.7 200 – 0.0 0.0

Lane 4 0 355 0 355 14.0 506 0.702 100 27.5 LOS B 14.0 109.7 200 – 0.0 0.0


Approach 76 1065 11 1152 14.0 0.702 26.6 LOS B 14.0 109.7


Lane 1 209 0 0 209 14.0 4571

0.458 100 21.0 LOS B 5.2 40.5 65 Turn Bay 0.0 0.0

Lane 2 0 226 0 226 14.0 776 0.290 100 17.1 LOS B 5.6 43.9 300 Turn Bay 0.0 0.0

Lane 3 0 226 0 226 14.0 776 0.290 100 17.1 LOS B 5.6 43.9 720 – 0.0 0.0


Approach 209 451 3 663 14.0 0.458 18.5 LOS B 5.6 43.9


Lane 1 560 5 0 565 14.0 761 0.743 100 20.8 LOS B 15.6 122.7 480 – 0.0 0.0

Lane 2 0 443 0 443 14.0 596 0.743 100 23.4 LOS B 16.8 131.6 480 – 0.0 0.0



Approach 560 448 336 1344 14.0 0.895 31.5 LOS C 16.8 131.6


Lane 1 654 0 0 654 14.0 1114 0.587 100 14.0 LOS A 15.4 121.0 305 – 0.0 0.0

Lane 2 0 336 0 336 14.0 560 0.600 100 31.8 LOS C 14.0 109.9 305 – 0.0 0.0

Lane 3 0 336 0 336 14.0 560 0.600 100 31.8 LOS C 14.0 109.9 305 – 0.0 0.0

Approach 654 672 0 1326 14.0 0.600 23.0 LOS B 15.4 121.0

Intersection 4485 14.0 0.895 25.8 LOS B 16.8 131.6


1 Reduced capacity due to a short lane effect





Old Wallgrove and Quarry Rd (Mini Link Roads )



HV Cap.Deg.Satn

LaneUtil.

AverageDelay

Level ofService

Lane Length

SL Type

Cap.Adj.


veh/h veh/h veh/h veh/h % veh/h v/c % sec veh m m % %South: Mini Link Rd

Lane 1 372 0 0 372 14.0 938 P 100 24.5 LOS B 12.4 96.9 300 – 0.0 0.0

Lane 2 372 0 0 372 14.0 938 P 100 24.5 LOS B 12.4 96.9 300 – 0.0 0.0


Approach 744 305 0 1049 14.0 0.699 30.5 LOS C 15.9 124.3

East: Old Wallgrove Rd East

Lane 1 48 0 0 48 14.0 2781

P 100 46.0 LOS D 2.2 17.0 70 Turn Bay 0.0 0.0

Lane 2 0 308 0 308 14.0 451 P 100 34.4 LOS C 14.8 116.3 100 – 0.0 18.7

Lane 3 0 308 0 308 14.0 451 P 100 34.4 LOS C 14.8 116.3 500 – 0.0 0.0

Lane 4 0 308 0 308 14.0 451 P 100 34.4 LOS C 14.8 116.3 500 – 0.0 0.0

Lane 5 0 0 265 265 14.0 4001

P 100 50.5 LOS D 13.8 107.8 110 Turn Bay 0.0 3.2

Approach 48 924 265 1237 14.0 0.682 38.3 LOS C 14.8 116.3

North: Private Access

Lane 1 26 18 0 44 14.0 640 P 100 30.6 LOS C 1.6 12.8 500 – 0.0 0.0


Approach 26 18 36 80 14.0 0.422 49.3 LOS D 2.2 17.3


Lane 1 104 0 0 104 14.0 3501

P 100 37.5 LOS C 4.2 32.8 80 Turn Bay 0.0 0.0

Lane 2 0 100 0 100 14.0 451 P 100 38.5 LOS C 4.7 36.5 500 – 0.0 0.0

Lane 3 0 100 0 100 14.0 451 P 100 38.5 LOS C 4.7 36.5 500 – 0.0 0.0

Lane 4 0 100 0 100 14.0 451 P 100 38.5 LOS C 4.7 36.5 500 – 0.0 0.0



Approach 104 300 599 1003 14.0 0.680 46.3 LOS D 15.9 125.0







Project: G:\21\22191\Tech\Supp Report SIDRA\OWR_Quarry.SIP8000065, GHD SERVICES PTY LTD, ENTERPRISE





HV Cap.Deg.Satn

LaneUtil.

AverageDelay

Level ofService

Lane Length

SL Type

Cap.Adj.



Lane 1 458 0 0 458 14.0 1066 P 100 20.2 LOS B 13.5 106.0 300 – 0.0 0.0

Lane 2 458 0 0 458 14.0 1066 P 100 20.2 LOS B 13.5 106.0 300 – 0.0 0.0


Approach 916 252 0 1168 14.0 0.797 27.7 LOS B 14.8 116.1



Lane 2 0 193 0 193 14.0 256 P 100 50.0 LOS D 11.0 86.1 100 – 0.0 0.0

Lane 3 0 193 0 193 14.0 256 P 100 50.0 LOS D 11.0 86.1 500 – 0.0 0.0

Lane 4 0 193 0 193 14.0 256 P 100 50.0 LOS D 11.0 86.1 500 – 0.0 0.0


Approach 50 578 51 679 14.0 0.753 51.5 LOS D 11.0 86.1


Lane 1 213 208 0 421 14.0 571 P 100 43.0 LOS D 22.0 172.8 500 – 0.0 0.0


Approach 213 208 106 527 14.0 0.746 48.7 LOS D 22.0 172.8


Lane 1 30 0 0 30 14.0 4461

P 100 23.7 LOS B 0.8 6.6 80 Turn Bay 0.0 0.0

Lane 2 0 310 0 310 14.0 767 P 100 25.5 LOS B 12.5 97.7 500 – 0.0 0.0

Lane 3 0 310 0 310 14.0 767 P 100 25.5 LOS B 12.5 97.7 500 – 0.0 0.0

Lane 4 0 310 0 310 14.0 767 P 100 25.5 LOS B 12.5 97.7 500 – 0.0 0.0

Lane 5 0 0 487 487 14.0 6101

P 100 43.9 LOS D 25.3 198.3 160 Turn Bay 0.0 24.5

Lane 6 0 0 487 487 14.0 6101

P 100 43.9 LOS D 25.3 198.3 160 Turn Bay 0.0 24.5

Approach 30 929 974 1933 14.0 0.798 34.8 LOS C 25.3 198.3












HV Cap.Deg.Satn

LaneUtil.

AverageDelay

Level ofService

Lane Length

SL Type

Cap.Adj.



Lane 1 263 0 0 263 14.0 824 0.318 100 28.1 LOS B 9.3 72.7 300 – 0.0 0.0

Lane 2 263 0 0 263 14.0 824 0.318 100 28.1 LOS B 9.3 72.7 300 – 0.0 0.0


Approach 525 285 0 810 14.0 0.592 32.8 LOS C 13.7 107.5


Lane 1 53 0 0 53 14.0 3021

0.175 100 39.5 LOS C 2.2 17.0 70 Turn Bay 0.0 0.0

Lane 2 0 340 0 340 14.0 572 0.595 100 25.7 LOS B 13.7 107.5 100 – 0.0 11.5

Lane 3 0 340 0 340 14.0 572 0.595 100 25.7 LOS B 13.7 107.5 500 – 0.0 0.0

Lane 4 0 340 0 340 14.0 572 0.595 100 25.7 LOS B 13.7 107.5 500 – 0.0 0.0


Approach 53 1020 154 1227 14.0 0.595 30.4 LOS C 13.7 107.5


Lane 1 20 31 0 51 14.0 667 0.077 100 28.3 LOS B 1.9 14.6 500 – 0.0 0.0


Approach 20 31 37 88 14.0 0.434 46.7 LOS D 2.3 17.8


Lane 1 156 0 0 156 14.0 3821

0.408 100 32.6 LOS C 5.8 45.5 80 Turn Bay 0.0 0.0

Lane 2 0 114 0 114 14.0 572 0.199 100 32.0 LOS C 4.8 37.8 500 – 0.0 0.0

Lane 3 0 114 0 114 14.0 572 0.199 100 32.0 LOS C 4.8 37.8 500 – 0.0 0.0

Lane 4 0 114 0 114 14.0 572 0.199 100 32.0 LOS C 4.8 37.8 500 – 0.0 0.0



Approach 156 341 334 831 14.0 0.587 43.0 LOS D 9.3 72.6











HV Cap.Deg.Satn

LaneUtil.

AverageDelay

Level ofService

Lane Length

SL Type

Cap.Adj.



Lane 1 166 0 0 166 14.0 895 0.185 100 23.8 LOS B 5.0 39.4 300 – 0.0 0.0

Lane 2 166 0 0 166 14.0 895 0.185 100 23.8 LOS B 5.0 39.4 300 – 0.0 0.0


Approach 332 126 0 458 14.0 0.419 30.8 LOS C 6.4 50.5


Lane 1 52 0 0 52 14.0 2621

0.199 100 51.6 LOS D 2.5 19.8 70 Turn Bay 0.0 0.0

Lane 2 0 247 0 247 14.0 361 0.683 100 40.8 LOS C 12.7 99.7 100 – 0.0 4.8

Lane 3 0 247 0 247 14.0 361 0.683 100 40.8 LOS C 12.7 99.7 500 – 0.0 0.0

Lane 4 0 247 0 247 14.0 361 0.683 100 40.8 LOS C 12.7 99.7 500 – 0.0 0.0


Approach 52 740 72 864 14.0 0.683 43.8 LOS D 12.7 99.7


Lane 1 235 190 0 425 14.0 634 0.670 100 39.1 LOS C 20.9 163.7 500 – 0.0 0.0


Approach 235 190 115 540 14.0 0.670 44.2 LOS D 20.9 163.7


Lane 1 25 0 0 25 14.0 4841

0.052 100 20.7 LOS B 0.6 4.9 80 Turn Bay 0.0 0.0

Lane 2 0 363 0 363 14.0 782 0.464 100 25.7 LOS B 14.9 117.1 500 – 0.0 0.0

Lane 3 0 363 0 363 14.0 782 0.464 100 25.7 LOS B 14.9 117.1 500 – 0.0 0.0

Lane 4 0 363 0 363 14.0 782 0.464 100 25.7 LOS B 14.9 117.1 500 – 0.0 0.0



Approach 25 1089 709 1823 14.0 0.674 34.1 LOS C 18.2 142.8







11 21/22191/188178

Attachment C – Corrected REF SIDRA Outputs

1

Iwan Smith

From: Mark Besley <[email protected]> on behalf of SIDRA Solutions Technical Support <[email protected]>

Sent: Monday, 17 December 2012 4:55 PMTo: Iwan SmithSubject: RE: Short-lane overflow and not-a-number error

Dear Iwan Thank you for your email and for attaching the project file. I had to look at our Support archive to remind myself about our previous correspondence which appears to have been related to timing calculation problems. “NaN” results ideally should never occur and indicate that some unexpected condition has occurred in the program that was not properly handled. However in your case, I was able to get proper results for delay and LOS (copied below). My thought is that this is something that was fixed in an update to Version 5.1 and perhaps you do not have the latest version. This is the first thing that you should check – the current version is 5.1.13.2093. I would expect no difference from version 5.1.12 as the most recent changes are only related to Windows 8 compatibility. I do not have any general advice about avoiding “NaN” results – your best option is to report such cases to us as you have done. I also agree with your statement that changing the short lane description to a different lane would not apply in a case like this. Please email us again if you wish to discuss this case further. Regards Mark Besley Director SIDRA SOLUTIONS Phone: +613 9857 4943 | Fax: +613 9857 7462 Address: PO Box 1075G Greythorn VIC 3104 Australia Email: [email protected] Web: www.sidrasolutions.com SIDRA News: www.sidrasolutions.com/subscribe.aspx SIDRA Forums: www.sidrasolutions.com/forums Akcelik & Associates Pty Ltd | ABN 79 088 889 687 | Management Systems Registered to ISO 9001 Disclaimer: If you are not the intended recipient of this e-mail, you are notified that any use or distribution of this message or its attachment is prohibited, and no confidentiality or privilege belonging to AKCELIK & ASSOCIATES Pty Ltd is waived or lost by any mistaken transmission to you. Notification of the sender about this unintended transmission will be appreciated.

LANE SUMMARY Site: AM 2021

(Southern Intersection) Wallgrove Rd, Mini Link Rd and M7 Ramp Signals - Fixed Time Cycle Time = 120 seconds (User-Given Cycle Time)

Lane Use and Performance

2

Demand Flows HV Cap. Deg. Satn

Lane Util.

Average Delay

Level of Service

95% Back of Queue Lane Length SL Type Cap. Adj.

Prob. Block.

L T R Total Vehicles Distance

veh/h veh/h veh/h veh/h % veh/h v/c % sec veh m m % % South: Wallgrove Rd South Lane 1 778 0 0 778 14.0 778 1 1.000 3 100 18.0 8 LOS B 8 21.9 8 171.6 8 105 Turn Bay 0.0 50.1 Lane 2 42 0 181 0 223 14.0 404 0.552 100 44.1 LOS D 11.0 86.0 220 – 0.0 0.0 Lane 3 0 232 0 232 14.0 421 0.552 100 44.0 LOS D 11.4 89.6 220 – 0.0 0.0 Lane 4 0 0 170 170 14.0 199 0.852 100 64.9 LOS E 10.4 81.7 170 Turn Bay 0.0 0.0 Lane 5 0 0 170 170 14.0 199 0.852 100 64.9 LOS E 10.4 81.7 170 Turn Bay 0.0 0.0 Approach 820 413 339 1572 14.0 1.000 35.7 LOS C 21.9 171.6 East: M7 Off/Onload ramp Lane 1 13 111 0 124 14.0 124 1 1.000 3 100 48.4 8 LOS D 8 6.2 8 49.0 8 30 Turn Bay 0.0 50.0 Lane 2 0 363 0 363 14.0 361 1.004 100 101.5 LOS F 31.2 244.8 150 Turn Bay 0.0 50.0 Lane 3 0 0 166 166 14.0 290 1 0.573 100 31.0 LOS C 5.5 43.0 50 Turn Bay 0.0 0.0 Lane 4 0 0 310 310 14.0 540 0.573 100 33.5 LOS C 12.3 96.5 365 – 0.0 0.0 Approach 13 473 476 962 14.0 1.004 60.6 LOS E 31.2 244.8 North: Wallgrove Rd North Lane 1 35 327 0 362 14.0 395 0.914 100 65.7 LOS E 24.6 193.0 200 – 0.0 1.8 Lane 2 0 358 0 358 14.0 391 0.914 100 49.8 LOS D 22.5 176.6 200 – 0.0 0.0 Lane 3 0 358 0 358 14.0 391 0.914 100 49.8 LOS D 22.5 176.6 200 – 0.0 0.0 Lane 4 0 0 147 147 14.0 171 0.859 100 75.3 LOS F 9.6 75.2 115 Turn Bay 0.0 0.0 Lane 5 0 0 147 147 14.0 171 0.859 100 75.3 LOS F 9.6 75.2 70 Turn Bay 0.0 11.4 Approach 35 1042 293 1370 14.0 0.914 59.5 LOS E 24.6 193.0 West: Mini Link Rd Lane 1 50 40 0 90 6.2 314 0.287 41 6 51.5 LOS D 4.7 34.3 350 – 0.0 0.0 Lane 2 0 191 0 191 14.0 271 0.704 100 54.8 LOS D 11.1 87.1 350 – 0.0 0.0 Lane 3 0 0 396 396 14.0 455 0.870 100 63.6 LOS E 25.4 198.8 125 Turn Bay 0.0 47.6 Lane 4 0 0 338 338 14.0 389 1 0.870 100 63.1 LOS E 21.2 165.9 105 Turn Bay 0.0 47.0 Approach 50 231 734 1015 13.3 0.870 60.7 LOS E 25.4 198.8 Intersection 4937 13.8 1.004 52.1 LOS D 31.2 244.8

From: Iwan Smith [mailto:[email protected]] Sent: Monday, 17 December 2012 3:08 PM To: SIDRA Solutions Technical Support Subject: Short-lane overflow and not-a-number error Hi I have previously raised a query with you in February of this year regarding “unable to process” errors in a model with a short-lane and a long cycle time. I am having similar problems with the same model, where a short lane with a low flow is reporting “not a number” results for lane delay and incorrectly displaying the level-of-service for that approach. I have attached a copy of the relevant file, the intersection that is causing the issue is (AM 2021) on the eastern approach, where lane 1 is overflowing (model attached). I have created a copy of this network and tried lengthening the short lane in question; it seems that simply lengthening the lane by 5m resolved the “NaN” issue (although the short lane still overflows). My question is really how to deal with a situation like this (which seems very rare, I haven’t really encountered this in any other models)? Previous advice I have had from Rahmi recommended changing the short lane behaviour such that the lane that does overflow is continuous and the lane that feeds it is coded as short, but that doesn’t seem to apply in this case. The model does look to be sensitive to overflow of this bay, so modelling as a short lane is required, and the results given by the 35m version are almost identical to the 30m version (reported movement delays are within 2 or 3 seconds and the overall intersection delay is within 1 second). Reported queue lengths under the 35m version on the eastern approach are actually longer than the 30m version, which seems more conservative. Is it simply not possible to model this intersection correctly under the 30m scenario, or is there another parameter in the set-up of the model that has been incorrectly specified?

3

Many thanks for your help. Iwan Smith Team Leader – Transport Modelling GHD T: +61 2 9239 7405 | V: 217405 | M: 0407 439 100 | E: [email protected] Level 15 133 Castlereagh Street Sydney NSW 2000 Australia | www.ghd.com WATER | ENERGY & RESOURCES | ENVIRONMENT | PROPERTY & BUILDINGS | TRANSPORTATION Please consider our environment before printing this email _____________________ This email and all attachments are confidential. For further important information about emails sent to or from GHD or if you have received this email in error, please refer to http://www.ghd.com/emaildisclaimer.html . _____________________ This e-mail has been scanned for viruses by MessageLabs. _____________________ This e-mail has been scanned for viruses by MessageLabs.

Appendix C

Supplementary flooding and drainage assessment

8 February 2013

Roads and Maritime Services PO Box 973 PARRAMATTA NSW 2124

Attention: Mr Matty Mathivanar

RE: Proposed Upgrade of Old Wallgrove Road - Response to Flood and Drainage Related Comments Contained in Stakeholder Submissions to the REF

Dear Sir,

This letter addresses the flooding and drainage related issues that are contained in three submissions which were forwarded to the Roads & Maritime Services (RMS) in response to the recently exhibited Review of Environmental Factors (REF) t for the proposed upgrade of Old Wallgrove Road at Eastern Creek. The three respondents who raised flood and drainage related issues and the dates of their submissions were:

Westlink M7 - 23 November 2012

Brown Consulting (on behalf of Jacfin Pty Ltd) - 23 November 2012.

Blacktown City Council (BCC) - 26 November 2012

The following sections of this letter provide a brief background to the scope of the flooding and drainage investigation that was undertaken by Lyall & Associates (L&A) as part of the REF, as well as our response to the issues raised by the aforementioned respondents.

1. Background

The scope of the investigation undertaken by L&A as part of the REF comprised the following tasks:

Review of the concept drainage design prepared by AECOM for the proposed road upgrade works.

Assess the impact of the road upgrade works will have on the hydrologic regime of receiving watercourses into which the new pavement drainage system for the upgraded sections of road will discharge.

Assess the impact of the construction of two new bridges associated with the widening of Wallgrove Road will have on local flooding conditions.

Develop an erosion and sediment control strategy for the construction phase of the proposed road upgrade.

The findings and recommendations of the investigation are contained in our 2012 report titled “Drainage Investigation – Old Wallgrove Road Upgrade - Eastern Creek”. Based on the findings of the investigation, a number of recommendations were made for incorporation into the detailed design for the road upgrade works. These recommendations were aimed at mitigating the flooding and drainage related impacts and improving the constructability of the road works.

2. Response to Issues Raised in Westlink M7 Submission of 23 November 2012 Issue: “The Lyall & Associates Drainage Report does not clarify the maximum extent of both spills and stormwater entering the M7 Motorway Basins, which could become an environmental issue if they exceed the maximum design capacity of the original design. WSO Co requests confirmation as to how the Old Wallgrove Rd upgrade design is planning to incorporate the use of the M7 Motorway Basins without posing possible risks to the maximum capacity allowable.” Response: Figure 5.1 of our report shows the extent of the road network that will contribute to flow discharging to the existing M7 Motorway basins, whilst Section 5.4 of our report sets out the findings of an investigation into the impact the discharge of road runoff will have on the operation of these structures in terms of their water quantity and quality objectives. The investigation found that the road upgrade will not compromise the water quality objectives set as part of the original design of the basins. The investigation did find that the road upgrade will increase the depth of flow over the spillway of Basin 18.01, which functions as a combined water quantity/quality control basin, by between 50-100 mm for the 100 year average recurrence interval (ARI) event. It was a recommendation of our report that the capacity of the existing spillway be checked during detailed design to confirm its suitability to cater for the increased depth of flow. With regard to incident management control, the existing basins incorporate provision for the capture of at least 50 m3 of spill material. It is RMS’ intention to rely on this existing provision to manage any spill material that might originate from the upgraded section of the road. Issue: “The REF refers to a possible flooding of the M7 Administration Offices, Incident Control Room, and associated computer storage areas, from the discharge of the first pavement drainage along Wallgrove Road. WSO Co requests further design detailing and clarification of this concern.” Response: In Section 5.4.2 of our report it is stated that it may be necessary to enlarge the cross sectional area of the grass lined channel which runs in a southerly direction along the western side of the Westlink M7 Operations Centre to prevent it from surcharging more frequently. It is noted that the said channel is located at the southern end of the Operations Centre, well away from the Administration Office, Incident Control Room and associated computer storage areas. That said, it was a recommendation of our report that measures be undertaken to prevent the more frequent surcharge of the channel, thus ensuring that the proposed road upgrade will not exacerbate flooding conditions in any part of the Operations Centre. 3. Response to Issues Raised in Brown Consulting Submission of 23 November 2012 Issue: “The proposed drainage strategy and temporary sediment basin shown on Figure 3-7a has a severe impact on the development potential of Lot 11, particularly on the corner of Eastern Creek Drive. Jackfin strongly objects to the location of the temporary sediment basin and find this an unacceptable treatment for this prominent corner location for employment land.” Response: Subsequent to studies undertaken as part of the REF, a review of the erosion and sediment control strategy described in our report has been undertaken with the benefit of early construction

staging plans which have been prepared by the designers of the road upgrade project. Based on the findings of the Review, it has been determined that the temporary sediment retention basin shown on Figure 3.7a of our report, east of the intersection of Old Wallgrove Road and Eastern Creek Drive can be omitted in favour of more localised control measures such as:

temporary revegetation/rehabilitation works to reduce the extent of disturbed surfaces;

application of temporary surface treatments or blanketing on exposed earth surfaces;

sediment barriers and sumps, in series where necessary;

vegetative buffer strips; and

stabilised drainage lines incorporating rock check dams at regular intervals.

Issue: “It is our submission that there is a better solution to the drainage treatment which would reduce the impacts on the development potential of the Jacfin land. As part of the industrial subdivision a temporary detention basin has been constructed near the bend in Eastern Creek Drive prior to discharging into Eskdale Creek.

The suggested approach is that RMS should drain Old Wallgrove Road via a permanent pipe system to this current temporary detention facility which would remove the need for the proposed temporary sediment basin at the intersection as shown in Figure 4 below.

The temporary sediment basin shown in RMS Figure 3-7a on the corner of Old Wallgrove Road and Eastern Creek Drive must be removed.”

Response: It has been determined that the temporary sediment retention basin recommended east of the intersection of Old Wallgrove Road and Eastern Creek Drive can be omitted from the erosion and sediment control strategy for the road upgrade project. Refer to previous response for further details of alternative control measures.

4. Response to Issues Raised in BCC Submission of 26 November 2012

Issue: Refer comment 3(a) of BCC Submission of 26 November 2012.

Response: RMS would enter into further discussions and negotiations with BCC on making financial contribution towards the cost of maintaining the basins. As part of these negotiations a cost apportionment methodology would be agreed based on the impact caused by the road upgrade proposal.

Issue: Refer comment 3(b) of BCC Submission of 26 November 2012.

Response: Goodman International provided RMS with a plan which shows the extent of the catchments which were assumed by the designers of the M7 Business Hub development to contribute flow to the two basins which are south of Old Wallgrove Road. By inspection of the plan, it appears that approximately 900 metres of an upgraded Old Wallgrove Road (westbound lanes only) was assumed to drain to existing basins located at the southern end of Southridge Street (refer to as Basin 1 on the Goodman International plan) and at the eastern end of Capicure Drive (refer to as Basin 2 on the Goodman International plan), whilst the section of the Mini-link Road north of Capicure Drive was assumed to drain Basin 2 only.

By inspection of Figure 5.1 of our report, only a small section of Old Wallgrove Road will discharge to Bain 1 (refer magenta shaded area contributing to flow at Outlet Identifier P3), whilst no runoff from the new westbound lanes will contribute to flow discharging to Basin 2. Whilst the extent of the area along the Mini-link Road which is shown on Figure 5.1 of our report draining to Basin 2 differs from that shown on the Goodman International plan, by inspection the total area of upgraded road (i.e. both Old Wallgrove Road and the Mini-link Road) contributing flow to this basin will be less than assumed by Goodman International. Based on the above, the proposed road upgrade will not adversely impact the performance of Basins 1 and 2 in terms of both the rate and quality of stormwater discharging to the receiving drainage lines because the area of road surface that will contribute runoff to both basins will be less than was assumed by the designers of the Goodman International development). Issue: Refer comment 3(c) of BCC Submission of 26 November 2012. Response: The potential for the road upgrade proposal to impact the stage-discharge relationship of the existing detention basin which is located on the northern side of Eskdale Creek immediately west (upstream) of the Wallgrove Road crossing was identified in our report (refer Section 5.4.1). Whilst details of the basin and its outlet were not available at the time our report was prepared, a review of available LiDAR survey data showed that the invert level of the outlet pipe is located above the peak post-upgrade 100 year ARI flood level in Eskdale Creek. On this basis it was concluded that the road upgrade works would likely not adversely impact the stage-discharge relationship of the basin. However, it was a recommendation of our report that further analysis be undertaken during detailed design to confirm this finding. Issue: Refer comment 3(d) of BCC Submission of 26 November 2012. Response: No statement has been made in our report about the proposed stormwater management strategy for the road upgrade project complying with BCC’s drainage related policies.1 Issue: Refer comment 3(e) of BCC Submission of 26 November 2012. Response: The impacts of the road upgrade on peak flows at Peak Flow Location Identifier A (refer Figure 5.1 of our report) are discussed in Section 5.3.2 of our report. Specific mention is made in this section of the report of the changes that will occur in peak flows with reference to pre-developed conditions. RMS can confirm that Jacfin Pty Ltd has been consulted with regard to the impact the proposed road upgrade will have on drainage patterns downstream of the road corridor.

1 This reference may be contained in the main body of the REF. [RMS has advised that this is an incorrect

statement and should not have been incorporated in the main body of the REF. RMS has also advised that it does not consider it a requirement of the road upgrade proposal to strictly comply with BCC’s drainage related policies.

Issue: Refer comment 3(f) of BCC Submission of 26 November 2012. Response: The impact of the road upgrade in terms of its immediate impact on peak flows and flood levels in the receiving drainage lines has been documented in our report (refer Section 5 for details). Issue: Refer comment 3(g) of BCC Submission of 26 November 2012. Response: A review of the XPRAFTS model files provided by BCC identified that there is an inconsistency in the loss model which has been used to derive flood hydrographs for the pre- and post-developed Eskdale Creek catchment. Based on this finding, it is believed that Council’s pre-developed catchment model provides an underestimate of peak flows in the Eskdale Creek system. When Council’s pre-developed catchment model was rerun using the same ARBM loss model as has been input to the post-developed model, the peak 100 year ARI flow in Eskdale Creek at Wallgrove Road increased from 21.6 m3/s to 24.2 m3/s. This revised peak flow estimate compares more closely with that adopted in the REF of 27.4 m3/s (refer Table 5.1 of our report). A sensitivity analysis was undertaken whereby the HEC-RAS model for Eskdale Creek was rerun using Council’s revised peak flow estimate of 24.2 m3/s. The modelling showed that there is less than a 20 mm difference in peak flood levels in Eskdale Creek for the two peak flow estimates. Based on this finding, we believe that the adoption of the reduced peak 100 year ARI flow estimate of 24.2 m3/s would not alter the findings of the REF. Council mentions in its letter the need for RMS to extend the modelling to the outlet of the Eskdale Creek system in order to include the cumulative impacts of the M7 Motorway basins. It is our understanding that the assessment of the impact of the M7 Motorway and its basins would have on flooding behaviour on Eskdale Creek was undertaken as part of the design of the M7 Motorway, information on which was provided to Council at the time. We are of the opinion that the current assessment extends a sufficient distance downstream to demonstrate the impact the current road upgrade proposal will have on flooding behaviour on Eskdale Creek. That said, to assist Council further in its understanding of the potential impacts the road upgrade proposal could have on peak flows in Eskdale Creek should Basin 18.30 not function as its designers originally intended (i.e. should it not attenuate peak flows in Eskdale Creek downstream of the Wallgrove Road crossing), the DRAINS model developed as part of the REF was re-run assuming the new pavement drainage system for Old Wallgrove Road discharged directly to Eskdale Creek. The results of the modelling show that the peak 100 year ARI flow in Eskdale Creek at the Wallgrove Road crossing would not be increased by the road upgrade works should Basin B18.30 not attenuate peak flows discharging from the new pavement drainage system.

Issue: Refer comment 3(h) of BCC Submission of 26 November 2012. Response: A review of the hydrologic and hydraulic assessment which was undertaken by AECOM as part of the preparation of the concept design for the Old Wallgrove Road upgrade proposal was undertaken as part of our report. Based on the findings of the Review, it was concluded that the assessment undertaken by AECOM was reasonable. We are of the opinion that the hydrology relied upon by AECOM when preparing the concept design for the road upgrade proposal is adequate and the need to undertake more detailed catchment modelling is not justified given the minor impact the road works will have on peak flood levels in Reedy Creek and the fact that existing development located in the zone of influence of the road works is not affected by floods with ARI’s up to 100 years. Issue: Refer comment 3(i) of BCC Submission of 26 November 2012. Response: The treatment of stormwater outlets will be determined during the preparation of the detailed design. We trust that the responses set out in this letter address the flood and drainage related issues raised in the three submissions to RMS’ satisfaction. However, please do not hesitate to contact the undersigned should you wish to discuss further any aspect of our responses further. Yours faithfully Lyall & Associates Consulting Water Engineers

Scott Button Principal

old wallgrove road widening · 2019-10-03 · with the m4 motorway (at a new interchange) and the...

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