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structuralLocal Infrastructure and Servicing ReportforDepartment of HousingonBentley Regeneration Project

Job #: 12-299b

Local Infrastructure and Servicing Report

for

Department of Housing

on

Bentley Regeneration Project

June 2013

Revision Description Date

0 Local Structure Plan Issue 28 June 2013

1 Amended for new Local Structure Plan 20 September 2013

12-299 Bentley Regeneration Project Page i

Table of Contents

Table of Contents i

1 Introduction 1

2 Site Analysis 2

2.1 Physical Description 2 2.1.1 Landform 2

2.1.2 Soils 2

2.1.3 Potential and Actual Acid Sulphate Soils 3

2.2 Demolition 3

2.3 Existing Service Infrastructure 3 2.1.4 Roads 3

2.3.1 Drainage and Stormwater Management 4

2.3.2 Water Services 4

2.3.3 Sewer Services 4

2.3.4 Power Supply 5

2.3.5 Telecommunications 5

2.3.6 Gas Supply 6

3 Infrastructure and Servicing 7

3.1 Siteworks 7 3.1.1 General Earthworks 7

3.1.2 Remedial Earthworks 7

3.1.3 Results of Detailed Site Investigation 8

3.2 Stormwater Drainage Pipe Network and Disposal 8

3.3 Water Reticulation 8

3.4 Sewer Reticulation 9

3.5 Underground Power 10

3.6 Telecommunications 10

3.7 Gas 11

3.8 Staging 11

12-299 Bentley Regeneration Project Page ii

4 Infrastructure Co-ordination and Servicing 12

5 Conclusion 13

Appendices

Appendix One Existing Water Services

Appendix Two Existing Sewer Services

Appendix Three Existing Power Services

Appendix Four Western Power Feasibility Study

Appendix Five Western Power Feasibility Estimate

Appendix Six Existing Telstra Services

Appendix Seven Existing Nextgen and Amcom Services

Appendix Eight NBN Co Infrastructure

Appendix Nine Existing ATCO Gas Services

Appendix Ten ATCO Gas Disconnection Correspondence

12-299 Bentley Regeneration Project Page 1

1 Introduction

Pritchard Francis has prepared this Local Infrastructure and Servicing Report on the demolition and development of infrastructure services and the Local Authority engineering conditions expected to be required and imposed to serve the proposed development of Bentley Regeneration Precinct.

The landholding comprises of 25 hectares as highlighted below. The development site is bounded by Walpole Street to the north, Pollock Street and a primary school to the west, Manning Road to the south and Dumond Road to the east.

The following pages outline the expected earthworks, retaining walls, stormwater drainage, water reticulation, sewer reticulation, gas infrastructure and local authority engineering conditions required to serve the proposed development of the precinct.


2 Site Analysis

2.1 Physical Description

2.1.1 Landform

The central northern area of the site has a crest at RL 19m near the intersection of Taree Street and Oliver Place. This crest grades down to RL 15m at the roundabout of Dumond Street and Walpole Street on the north-western corner of the development and RL 13m at the intersection of Troon Court and Pollock Street to the north-east. A sump is located at the intersection of Holder Street with Walpole Street of RL 11.5m and also at Warwick Street intersection with Pitt Street of RL 12.5.

From the high point of RL 19m the site falls by 5 metres elevation over 230 metres to the existing Brownlie Towers (RL 14m) centrally located within the development. With the split level tower design, the southern face of the Brownlie Towers has a level of RL 12.0m and this subsequently falls to Manning Road at RL 9m over a distance of 370 metres.

2.1.2 Soils

An initial investigation and information provided by the Department of Housing revealed the presence of a former sand pit within the northern portion of the site which operated between the late 1940’s to early 1960’s. The sand pit was subsequently backfilled resulting in uncontrolled fill with thicknesses ranging from 5 to 10 metres across the pit. CPT testing was undertaken by Coffey Geotechnics which advise:

‘the presence of sand underlying the site with clayey sand / sandy clay inferred to be Guildford Formation encountered in the deeper probes at elevations ranging between 2m AHD and 5m AHD. The natural sand material below surface topsoil layers comprised fine to medium grained, siliceous sand in a medium dense to very dense condition. Some of the CPT plots from the southern part of the site indicate the possible presence of a cemented Coffee Rock layer within the natural sand profile.

CPT testing indicates that the historic quarry backfill material comprises predominantly sand extending to depths ranging up to 10m below existing surface elevations. The sandy backfill material is typically in a medium dense to dense condition within the surface 1m to 2m depth but then becomes loose to very loose with depth. Some of the CPT plots indicate the presence of localised layers within the backfill of possible buried crushed rock pavement and/or former well trafficked areas of the quarry that have been compacted by earthmoving machinery. In addition, some of the CPT plots indicate the presence of clayey and/or silty layers, typically 0.2m to 0.4m thick, within the deeper parts of the quarry, immediately above the quarry floor. These layers possibly representative of areas of the quarry floor that were excavated below the winter groundwater elevation and have subsequently been partially infilled with a layer of fine material deposited when submerged below the water table.’

The loose uncontrolled fill is to be addressed by Pritchard Francis during the forward works programme comprising of bulk earthworks and remediation of the Bentley Regeneration Project.


2.1.3 Potential and Actual Acid Sulphate Soils

Desktop work by Pritchard Francis and RPS has established via available mapping from the Department of Environment and Conservation (DEC) that the Redevelopment Precinct is within the moderate risk range for potential and actual acid sulphate soils (within three metres of the surface), predominantly due to the sites proximity to the river.

Designs for civil servicing and geotechnical improvement propose not to interfere with the water table (i.e. dewatering is most common way of activating PASS).

As part of their detailed site investigation, RPS completed 108 pHf and pHfox tests within the site with only one sample indicative of any actual acid sulphate soil (AASS). However it is considered that there is buffering capacity within the soils to neutralise any acid sulphate soils encountered.

2.2 Demolition

The removal of the Department of Housing properties on Girton Place, Oliver Place, Taree Street, Tresco Place, Soames Place and Mannock Road has already been undertaken prior to June 2013. A residence to the north-east on Walpole Street has also been demolished.

Additional properties near the intersection of Taree Street and Mannock Road are in the process of being demolished at the time of writing by the Department of Housing. The small shopping centre at the base of the Brownlie Towers will also be demolished at the appropriate time.

The community centre, Canning aquatic centre, youth community centre, scout hall, community garden centre, Canning tennis club, Canning tennis courts, netball courts, toilet block and library are yet to be removed. These community facilities will be maintained for as long as physically possible pending the commencement of the earthworks remediation and subdivisional works of the Bentley Regeneration Precinct and the development of any replacement facility.

All buildings will have hazardous materials (HAZMAT) assessments completed and supervision hold points to ensure the satisfactory removal of HAZMATs encountered.

2.3 Existing Service Infrastructure

2.1.4 Roads

All existing roads have been maintained to this point in time. The closure of the internal roads being Girton Place, Oliver Place, Taree Street, Tresco Place, Soames Place and Mannock Road will be undertaken via chain link fencing prior to the commencement of the earthworks remediation to ensure the site is safe and secure during the operation. Alternative footpath routes will be provided to ensure pedestrian movements can be maintained across the development from the Bentley Towers to Pollock Street.


2.3.1 Drainage and Stormwater Management

The existing stormwater network within the precinct is limited as the majority of the landholding is natural ground rather than hard surfaces. The demolition and upgrades of stormwater lines will be required as part of the works to the requirements of the Local Authority.

2.3.2 Water Services

Water Corporation digital data has been sourced by Pritchard Francis which denotes all existing infrastructure in the vicinity of the development and has been provided in Appendix One.

With the demolition of the existing properties on the internal roads, the water reticulation mains to Girton Place, Oliver Place, Taree Street, Tresco Place, Soames Place and Mannock Road will be removed prior to the geotechnical remediation. The contractor of the works will be required to engage the Water Corporation to complete the necessary capping of the existing mains which will be required in Taree Street (twice), Palmerston Road (twice) and one capping in Coolgardie Street. Once these disconnections have been achieved by the Water Corporation, the removal of the mains can commence.

The surrounding road networks of Dumond Road, Walpole Street and Pollock Street contain nominal Water Corporation main sizes of 150CI, 100AC and 205CI respectively. A notable main of 610S-6 is located on the southern boundary of Manning Road whilst a 300 main is located in Boundary Street, 300 metres north of the development.

Please refer to section 3.3 of this report for advice with regards to water reticulation upgrades for the Bentley Regeneration Precinct.

2.3.3 Sewer Services

Water Corporation digital data has been sourced by Pritchard Francis which denotes all existing infrastructure in the vicinity of the development and has been provided in Appendix Two.

The majority of the sewer services which serviced the previous dwellings on Girton Place, Oliver Place, Taree Street, Tresco Place, Soames Place and Mannock Road will be decommissioned by the Water Corporation and subsequently removed prior to the earthworks remediation. Some of these services however serve the Dumond Road, Walpole Street and Pollock Street properties from the back of house and therefore some of these lines will need to be either maintained, redirected or upgrades as part of the works.

All sewer infrastructures in the precinct grades to the south and is discharged of to the Manning Rd East Pump Station #9.

A large portion of the sewer pipes to be removed were formed from asbestos cement. This will result in additional excavation and removal costs to ensure the site handling and disposal of the asbestos containing material is performed in an approved manner. There are many vitreous clay sewer pipes on site; care must be taken when connecting into them as they can be fragile. Additional work will be required to connect PVC pipes into the vitreous clay pipes, and sections will be replaced to ensure longevity.


Some existing sewer services on the edges of the site will be retained and connected into new services to maintain service to existing lots. Sewer services for lots external to the development site grade through the site. These services must be maintained so this must be considered when considering the timing of removal and installation of new services. A flow management plan will be developed in liaison with the Water Corporation to ensure limited impact on upstream services.

Please refer to section 3.4 of this report for advice with regards to sewer reticulation upgrades for the Bentley Regeneration Precinct.

2.3.4 Power Supply

Western Power digital data has been sourced by Pritchard Francis which denotes all existing infrastructure in the vicinity of the development and has been provided in Appendix Three.

Advice received from Western Power and 3E Consulting Engineers indicates that the existing distribution network is not sufficient to serve the entire development and that network reinforcement must be undertaken as the development progresses.

Western Power advises that approximately 250 additional residential lots can be serviced with the existing infrastructure by connecting into feeders BTY537 and BTY508 on Walpole and Dumond Streets. The Western Power feeders in the area can be seen in Appendix Four within the Feasibility Study Report. The Western Power Feasibility Estimate is provided within Appendix Five. It must be noted that the Western Power report was based on an earlier concept layout of the site, however the conclusions and recommendations are still applicable to the current layout.

To service later stages with an ultimate load of 8 MVA a connection to BTY536 will be required which involves a significant extension of the line to bring it to site and interconnect it with other feeders. From the corner of Hayman and Marquis Streets this extension would involve approximately 3km of HV 400mm2 aluminium cables and up to 6 ring main units. This line extension will be as an underground cable that will be installed with boring or open excavation where required by site conditions.

At least six additional transformer substations will be required on site to support the additional development of the site. They will be a mix of sole use and district systems.

It must be noted that the available capacity on the network is allocated based on customer demand; it cannot be reserved so any delays in the project may affect the future availability of power.

2.3.5 Telecommunications

Existing Telstra infrastructure services the site. Due to the new site layout the majority of the pit and pipe infrastructure will be removed. The new development will be served by an NBN Co fibre system as the development exceeds 100 dwellings.

The removal of assets internal to the site will not impact external users as there are no key paths that traverse the site and all Telstra conduits enter the site from surrounding roads after serving bordering residences.


NBN construction has commenced in nearby areas up to the corner of Walpole and Taree Streets from the north. The developer will be required to provide a pipe and pit system into which NBN Co will place fibre to serve residences. NBN Co is responsible for providing ‘back haul’ links to ensure that the site is able to be serviced. Locations for NBN Co above ground fibre distribution hubs above will need to be coordinated at the detailed design stage.

There is existing Amcom and Nextgen/Visionstream telecommunications infrastructure near the development site however it does not present an issue for main construction works as the NBN will be used for all of the development’s communications requirements.

The location of telecommunications pits will need to be considered at the detailed design stage for any existing intersections that are modified for the site, particularly the Manning Road intersection which has multiple cables in its road reserve.

Please see Appendices Six, Seven and Eight for the Telstra, Amcom, Nextgen/Visionstream and NBN Co infrastructure respectively.

2.3.6 Gas Supply

Gas is currently supplied to site through ATCO Gas infrastructure and ATCO will be providing service to the future development. Pritchard Francis has obtained the digital ATCO Gas data which is provided in Appendix Nine.

ATCO Gas have already decommissioned infrastructure which previously serviced Girton Place, Oliver Place, Taree Street, Tresco Place, Soames Place and Mannock Road. The physical removal of these pipes will be undertaken by the civil contractor in the presence of ATCO Gas to ensure that any residual gas within the pipelines is removed prior to the demolition.

One final segment of infrastructure remains live and serves the swimming complex. Pritchard Francis has advised ATCO Gas that this service is no longer required and the decommissioning of this line may proceed.

Please refer to Appendix Ten for correspondence by ATCO Gas advising of the current state of works.


3 Infrastructure and Servicing

3.1 Siteworks

In accordance with the geotechnical investigatory reports by Coffey dated 2 November 2010, 23 January 2013 and 5 July 2013 the remediation of the loose, uncompacted in-situ material will be undertaken during the earthworks operation of the Bentley Regeneration Project. In order for these works to be undertaken successfully in a cost-effective manner, the following steps and/or recommendations have been made.

3.1.1 General Earthworks

All topsoil across the site shall be stripped and stockpiled in a suitable location. With the large amounts of topsoil to be generated from the site and limited surface areas available in the Public Open Spaces (POS), Pritchard Francis will investigate the opportunity to mine clean sand from the proposed POS’s before placing and compacting the topsoil to the borrow pits. It will be the project’s intent to maintain all topsoil on site in a cost effective and sustainable manner.

Existing inert materials inclusive of footpaths, kerbing and bricks shall be removed and stockpiled in a suitable location. It will be recommended that these materials be placed and compacted in a controlled fashion deep within Public Open Space areas to minimise cost and traffic movements to and from site. Previous stripped topsoil can be compacted over the inert materials as a protective barrier.

Existing pavement materials of limestone and roadbase shall be stripped and stockpiled in a suitable location. These materials will be re-used during the subdivisional phase of the project. It will be the intent of this project to maintain all valuable material on site. Asphalt will be removed from site and disposed of at an appropriate facility.

The requirement for, and the height of retaining walls shall be minimised across the site through the appropriate use of cut to fill and minor grading to lots.

3.1.2 Remedial Earthworks

In order to rectify the loose, uncompacted in-situ material on site, several earthworks methodologies and construction techniques have been assessed for their effectiveness, construction duration, effect on adjacent landowners, cost and risk.

Traditional methods of cut to fill and proof rolling have been suggested, however new technologies including vibrofloatation, high energy impact rolling or deep compaction are also being considered due to their ability to work around existing vegetation to be located in future POS’s whilst also being cost-saving techniques in comparison to the traditional methods. A combination of several techniques dependent upon the depth of rectification and location of adjacent residents will be thoughtfully considered during the design. Pritchard Francis notes that the traditional techniques work will result in all vegetation being cleared.

Whilst completing the earthworks in accordance with the above philosophy, the natural surface of the Bentley Regeneration Precinct will be modified slightly to ensure smooth grades result in both the north-south and east-west


plains of the development. This allows for the integration of the existing ground levels, features and the requirements of built form.

In order to achieve an even cut to fill earthworked site, the excavation of basements where 5 to 8 storey structure are anticipated will be considered as a further cost saving technique. Further cost benefits also result from the excavation of such basements as the depth of the loose, uncompacted in-situ material is reduced by 2 – 3 metres.

3.1.3 Results of Detailed Site Investigation

The Aurora Environmental Targeted Detailed Site Investigation issued on August 7, 2013 identified areas of soil impacted by Organochloride Pesticides, including Aldrin. The extent of impact is limited to existing building footprints, which matches previous government practice for application of pesticides below building pads. Aurora notes that onsite treatment and containment of contamination is preferred by the Department of Environmental Regulation. The Aurora report estimates the volume of the HIL-A (Health Investigation Level) soil is 175 m3, and the volume of EIL-A (Ecological Investigation Level) impacted soil is 20,500 m3.

Pritchard Francis has proposed that the impacted soil will be contained within cells in road reserves. This will prevent access to the material, while also being sufficiently clear of the water table to prevent further contamination. Memorials on titles of standard lots will also be avoided with this method.

Asbestos Containing Material was also identified across the site. The ACM is considered to be small-scale ACM impact as defined by the Department of Health. ACM from the house pads will be included in the cells. The stockpiled material and remaining asbestos impacted soils can then be buried at depth. ACM in existing service pipework will be dealt with separately and removed from site.

3.2 Stormwater Drainage Pipe Network and Disposal

The transmission of stormwater drainage shall be in accordance with the requirements of the City of Canning and the Department of Water where storms to 1:5 are piped and 1:100 directed to compensation basins.

3.3 Water Reticulation

Correspondence between Kevin Purcher of the Water Corporation and Cossill & Webley dated 3 December 2009 advised:

‘Reticulated water is currently available to the subject area. As the density of the proposed development will be significantly greater than the existing development density, revised planning and hydraulic analysis will need to be undertaken to determine service and design requirements onsite and any upgrades required to connect into the system. If extensions are required, all water mains must be laid within the existing road reserves and proposed road reserves within the development site, on the correct alignment and in accordance with the Utility Providers Code of Practice.

With further correspondence dated 5 May 2010 advising:


‘The proposed development area falls within the Kewdale-South Perth Gravity Zone. An upgrading of the current system is required to prevent existing customers being affected by the development.

The recommended upgrade is to provide a 1.3 km DN300 distribution main through the project area. This DN300 distribution main will be connected to the DN610 at the junction of Manning Rd and Dumond St and also to the DN300 at the junction of Boundary St and Taree St. A cross connection to the existing DN200 at the junction of Walpole St and Taree St is also required.

Reticulation main to serve the various precincts must be provided off the proposed DN300 distribution main. The sizes of the reticulation mains are not determined. They must be of adequate size to serve the precincts without incurring excessive head losses between the DN300 distribution main and the high rise buildings.

A route for the headworks main will also be required, approximately 20 metres wide. The route shall be in the form of a road reserve.’

Pritchard Francis has liaised with Kevin Purcher of the Water Corporation during May and June 2013 to recommence discussions with regards to the water reticulation network of the Bentley Regeneration Precinct. Revised plans and potential dwelling figures for the development area were provided to the Water Corporation which have since been issued to the land development section for review. A formal response is expected within the forthcoming weeks, however preliminary advice received from Kevin Purcher advised that a DN300 will still be required to connect to the existing DN610 at Manning Road and be extended through the primary road reserve of the Bentley Regeneration Precinct to Boundary Road. The developer would be required to install this main early on within the development to ensure pressure and flow is available to the first high-rise apartment dwellings of the initial stages.

3.4 Sewer Reticulation

Correspondence between Kevin Purcher of the Water Corporation and Cossill & Webley dated 3 December 2009 advised:

‘Reticulated sewerage is currently available to the subject area. Consistent with the advice above for water, the increase in development density will require a revised planning analysis to determine service and design requirements.

Existing pump stations and sewerage mains may need to be upgraded due to this increase in development density. If an upgrade of a pump station is required, appropriate land will need to be provided for the new works and the odour buffer that will surround the works. The extent of the buffers for all pump stations, existing or upgraded, should be determined at the development planning/design stage to ensure that only compatible land use is within the buffer.

If extensions are required, all sewer mains should be laid within the existing road reserves and proposed road reserves within the development site, on the correct alignment and in accordance with the Utility Providers Code of Practice.’


With further correspondence dated 5 May 2010 advising:

‘Most of the proposed development area falls within the Manning Rd East PS catchment, and the remainder of the area falls within the Palmerston St PS catchment. The Manning Rd E PS pumps through a DN300 pressure main to Palmerston St PS. Palmerston St PS pumps to Cannington Main PS through a DN300 pressure main.

The proposed redevelopment will not activate any required upgrades to the existing infrastructure in the medium term.

The revised long term pump rate at Palmerston St PS is greater than the existing pump rate. It is likely that the pump station will need to be upgraded in the long term.

A complete review of the Cannington, East Cannington and Kewdale Sewer Districts are scheduled for 2011. It is recommended that the land use changes resulting from the Brownlie Towers redevelopment be implemented under that review. The review will also further investigate and schedule the proposed upgrade of Palmerston St PS.’

Pritchard Francis has liaised with Kevin Purcher of the Water Corporation during May and June 2013 to recommence discussions with regards to the sewer reticulation network of the Bentley Regeneration Precinct. Revised plans and potential dwelling figures for the development area were provided to the Water Corporation which have been issued to the land development section for review. A formal response is expected within the forthcoming weeks, however preliminary advice received from Kevin Purcher advised that upgrades to the Water Corporation pump station would not be a requirement of the developer as the peak load from the dwellings would not be expected for another 8 to 10 years.

3.5 Underground Power

Please refer to section 2.3.5 and Appendix Four and Five for information regarding underground power upgrades to serve the site.

Pritchard Francis will be required to submit Water Corporation water reticulation plans to 3E Consulting Engineers during the detailed design phase in order to coordinate the works and such that open trenches can be provided to lay the underground power infrastructure.

3.6 Telecommunications

Please refer to section 2.3.6 and Appendix Six, Seven and Eight for information regarding existing services to the site.

Pritchard Francis will be required to submit Water Corporation water reticulation plans to 3E Consulting Engineers during the detailed design phase in order to coordinate the works and such that open trenches can be provided to lay the telecommunications pit and pipe infrastructure.


3.7 Gas

Pritchard Francis will be required to submit Water Corporation water reticulation plans to ATCO Gas during the detailed design phase in order to coordinate the works and such that open trenches can be provided to lay the ATCO Gas infrastructure.

3.8 Staging

It is anticipated that Bentley Regeneration Project will be developed in stages over the coming years, dependant on the requirements of the proponents and market conditions.

Forward works activities are expected to be completed in 2014 with the initial stage of Civil Subdivision works occurring in 2015. It is anticipated that the forward works will include site fencing, demolition of structures, remediation as required, geotechnical improvement, bulk earthworks and revised access to existing Towers and facilities. The anticipated civil subdivision works will include final earthworks, installation of services, installation of the road network and landscaping.

There is also the requirement of an initial residential building on site early in 2016 to which Pritchard Francis have provided a report of early build opportunities based upon existing service infrastructure.

The subdivision stages will tie into the existing road network and conjoin with existing utility infrastructure for the most efficient design. Minor upgrades will be required to allow for the increased demands on the respective authority networks.


4 Infrastructure Co-ordination and Servicing

At the completion of the removal of all redundant services within the Bentley Regeneration Precinct, Pritchard Francis will be required to coordinate the design, documentation and installation of the services inclusive of sewer reticulation, water reticulation, stormwater drainage, telecommunications, gas reticulation and underground power. This coordination will be undertaken in accordance with the Utility Providers Code of Practice for Western Australia which clearly defines the standard alignment of services to be installed to all road reserves. All design and documentation of such services will be submitted to the relevant authorities for approval prior to installation. These authorities will include, but not limited to:

▪ City of Canning ▪ Water Corporation ▪ ATCO Gas ▪ Western Power ▪ Department of Housing ▪ NBN Co / Telstra ▪ Main Roads Western Australia


5 Conclusion

This report confirms that the proposed development should be capable of being served with all of the essential services subject to the upgrades as detailed in the report.


Appendices











ACN: 008 891 [email protected]

Facsimile: (08) 9382 5199

Subiaco WA 6904PO Box 2150

Level 1, 430 Roberts Road

305RC


Facsimile: (08) 9382 5199




Facsimile: (08) 9382 5199



DMS#: 4874659v1 1 File#: SDV/77/T118S23D(156)V1

Project Name: Brownlie Development, Bentley (MF010139)

Developer: Pritchard Francis Number of lots: 1315 Lots (New) March 2013

Feasibility Study

DMS#: 10534844v1 2 File#: AM/119/MF010139(DQM)V1

1. INTRODUCTION

3E Consulting Engineers has requested a Feasibility Study in the City of Canning. The name of the new development is Brownlie Development, Bentley. The location of the development is shown in Figure 1. Note that a previous feasibility study was done for this same development under project #MF010030 (refer to DM#6761636). 3E Consulting Engineers have requested a new feasibility study be undertaken with a 20% increase in load demand from the previous study.

Figure 1: Brownlie Development, Bentley. The location of stages for development is shown in Figure 2 and the following information was provided: Number of new lots 1315 Number of stages 6 Total new ADMD of all stages Approx. 8MVA


Power requirements: Stage 1 = 299 existing lots plus 0.3MVA by 2013 Stage 2 = 242 new lots, total of 1.3764MVA by 2014 Stage 3 = 394 new lots, total of 1.8552MVA by 2015

Stage 4 = 307 new lots, total of 1.5924MVA by 2016 Stage 5 = 46 new lots, total of 0.7176MVA by 2017 Stage 6 = 326 new lots, total of 2.1456MVA by 2018

Figure 2: Staging Plan


2. EXISTING INFRASTRUCTURE

Figure 3 below shows the location of the development project in respect to Western Power HV Network map. There are currently some High Voltage (HV) distribution networks near the areas of development. As shown in Figure 3, there are two feeders in the vicinity – BTY537 and BTY 508 feeders out of Bentley Zone Substation (BTY). BTY536 is another feeder near the development site. The distance between development site and Bentley Z/S is approximately 1.4km.

Figure 3: Existing Infrastructure – HV Distribution Network.


3. STUDY DETAILS The feasibility study was conducted considering committed load requests for other surrounding developments in the region. The initial analysis revealed that, for present network loads, the existing infrastructure would have limited capacity to supply the new load requested. Studies revealed that BTY 537 feeder or BTY 508 feeder may be able to supply up to stage 2 development (expected completion 2014). Supply can be taken from the BTY537 and BTY508 feeders along Walpole St and Dumond St respectively. If load for stage 1 is committed, it is advised to submit an application to request for detailed Planning Memo. Based on the forecast to supply ultimate load of 8MVA, it is proposed than the BTY536 feeder is extended to the area around the development site. Refer to figure 4 for a diagram of the proposed extension of BTY 536. This would involve installation of:

• approximately 2.85km of 400 sqmm AL XLPE; • approximately 6 RMUs in total to facilitate cut in to BTY536 feeder,

interconnections to other feeders and the supply of new loads. Note that the above proposed network reinforcement would be required to connect loads from stage 3 onwards. It should be noted that capacity can not be reserved for customers, and is allocated on a first come first serve basis. Due to the dynamic nature of the network, capacity constraints will alter over time. Should the development be delayed, the spare capacity on BTY 537, BTY 508 or BTY 536 feeders may be used up by other loads, therefore requiring additional reinforcements to the ones described above. The extra reinforcements are needed to assure that power supplies to the development are adequate. If the development is deferred, further reinforcements which have not been identified may be needed to connect the development as the network is fluid and dynamic. Network development is highly dependent on where load develops and grows in the region.


Figure 4: Proposed Network Reinforcement for Brownlie Development


4. CONCLUSION

For the assumptions made in the above study, the study results indicate that available capacity is limited, and could be taken up by other loads prior to this development. As a result, further studies for network reinforcements would be required at the time the development project is confirmed to proceed to determine the final network requirements. Reinforcement requirements may be significant in future years as a result of additional load connections/growth in the interim period.


5. GENERAL ASSESSMENT

The timing and type of reinforcement mentioned above is likely to change and are dependent on load uptake and developments in the region. It should be noted that cable laid in this area must be either 400 mm2 Al XLPE or 240 mm2 Cu XLPE. If overhead conductor is used it must be of 19/3.25 AAC construction. The details in this feasibility study are only indicative. Further in-depth study and analysis will be required to determine the exact requirement of the reinforcement works once a formal application to Western Power has been lodged. Western Power can neither reserve capacity nor guarantee supply to this development without a formal request being lodged. In order to provide a firm connection proposal and cost, a formal application to Western Power will have to be made, in accordance with our connection policies.

Your reference: 3E13014E Request reference: MF010139 Fax: 9225 2073 08 May 2013 3E Consulting Engineers Pty Ltd PO Box 3184 EAST PERTH WA 6892 Attention: Mr Jey Shivakumar Dear Jey, BROWNLIE DEVELOPMENT WESTERN POWER REF: MF010139, WAPC No: N/A In response to your request for a Feasibility Study, I am pleased to provide you with the attached report. Our Tax Invoice will be sent to you in due course. The amount due includes the standard fee of $775.00. The following is an estimated cost of the high voltage distribution works to provide electricity distribution capacity to your proposed development. This estimate is based on a desktop review of your requirements and the existing electrical network. FEASIBILITY ESTIMATE The estimated cost of the reinforcement works to your proposed development is $1,915,995.00, including GST. Please note the following important information about this estimated cost:

o It is an indicative figure only, to assist you to plan and make decisions about your project.

o The final quoted cost may be higher or lower than this estimate. In some cases, final quotes are significantly higher than estimates, because of ground conditions and other impediments identified during the site visit and / or fluctuations in the cost of materials and labour etc.

o This estimated cost is non-binding.

DISCLAIMER

o This information is based on information available today. o Western Power cannot reserve any capacity to accommodate the proposed

development unless a quotation is offered and accepted. o Western Power accepts no responsibility for any consequences resulting from

decisions made on the basis of information provided in this response. ANY QUESTIONS? If you have any questions, please telephone our Customer Contact Centre on 13 10 87 during business hours. Yours faithfully _______________ Rob Ramsden Branch Manager Customer Network Connections enc: Terms and Conditions

FEASIBILITY STUDY TERMS AND CONDITIONS 1. Terms and Conditions These terms and conditions shall form part of the contract unless specifically excluded in writing by an authorised representative of Western Power. 2. Consequential Loss Damages shall be limited to damages for direct and foreseeable loss attributable to breach or default under this Agreement. The rights of either party to damages for indirect or consequential loss are hereby excluded. Neither party shall be liable to the other for any loss of profit suffered by a party to this Agreement or any other person. 3. Modification A purported modification, variation or amendment of this Agreement including the scope of works or any waiver of any rights of any party or any approval or consent shall have no effect unless in writing and signed by the party to be charged, and may attract a subsequent fee. 4. Application of Acts and By-Law Nothing contained in these Terms and Conditions shall in any way limit the operation or effect of the Electricity Corporation Act 1994, Energy Corporations (Powers) Act 1994, Energy Corporations (Transitional and Consequential Provisions) Act 1994, or any Regulations, By-Laws or Orders made pursuant thereto. 5. Ownership of Works The whole of the electricity extension that forms the works carried out in accordance with the proposal is the property of Western Power and Western Power has the right to connect additional customers to any part of the extension. 6. Indicative Estimate This indicative estimate of the cost of electrical distribution [and transmission] works is ONLY AN INDICATIVE ESTIMATE. 7. Assumptions Western Power has calculated the indicative estimate on the basis of a "desktop study" only which includes information readily available at the time and certain assumptions regarding the project and costs. The information and assumptions may turn out to be incorrect or incomplete. 8. Fluctuations Construction costs, including materials and labour, are subject to fluctuation and may change significantly over time. The final quoted cost may be higher or lower. In some cases final quoted costs are SIGNIFICANTLY HIGHER than indicative estimates. 9. Liability Western Power has calculated the indicative estimate in good faith however Western Power, to the extent permitted by law, accepts no liability for any errors or omissions or for any discrepancy between the indicative estimate and the final quoted cost, if any.


Facsimile: (08) 9382 5199



structural

structural

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providing the right solution

civil

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civilPritchard Francis Pty Ltd

Level 1 430 Roberts Road PO Box 2150Subiaco WA 6904

Telephone: (08) 9382 5111Facsimile: (08) 9382 5199

[email protected]

www.pfeng.com.au

Unit 4/27-29 Dampier Terrace PO Box 3634Broome WA 6725

Telephone: (08) 9192 8015Facsimile: (08) 9192 8038

[email protected]

providing the right solution civ- civil - department of … · civ-cl providing the right solution...

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