LSP3
3.8 Activity Centres and Employment
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3403Rep7A 51 3.9 Pipeline Corridor
As noted previously, an easement containing the Parmelia Gas Pipeline is located along the western periphery of the LSP area, while the Dampier-Bunbury Gas Pipeline is located within an adjacent easement to the west within lot 346.
The DSP and Planning Bulletin 87 (PB87) establish a ‘default’ setback to the pipeline corridor, which is deemed to ensure an acceptable level of risk to future residents without requiring any additional works or improvements to the pipeline itself. Both the DSP and PB87 acknowledge that the default setbacks can be reduced where it can be demonstrated via a Qualitative Risk Assessment that the risk arising from the pipeline is within acceptable risk levels pursuant to PB87 and AS 2885. Consulting engineers Worley Parsons have prepared a Pipeline Risk Management Plan and Protection Plan, which constitutes a QRA for the purpose of the DSP and PB87. The Pipeline Risk Management Plan and Protection Plan is informed by a risk assessment undertaken by Worley Parsons, APA Group (Parmelia Pipeline operators), and DBP (Dampier to Bunbury Pipeline operators).
A full copy of the Worley Parsons report is included as Appendix 4, with the key findings / recommendations summarised below.
The LSP reduces the default setbacks such that residential development is proposed to be separated from the pipeline corridor by an 18m wide access street. In order to maintain an acceptable level of risk whilst allowing reduced setbacks, the QRA recommends the following physical works to be undertaken:
• Increased safety signage;
• Bollards to prevent vehicle access into the corridor;
• Road crossing to comply with AS2885 (concrete slab and minimum separation of services from pipeline);
• Installation of temporary fencing to restrict access to the pipeline during construction;
and
• Ground cover to comply with APA requirements.
In addition, the QRA identifies a series of practical actions to be undertaken during construction in order to ensure that safety standards are satisfied.
The QRA concludes that provided the abovementioned actions are undertaken, the reduced setback proposed by the LSP will achieve an acceptable level of risk.
The LSP reserves the Pipeline Corridor as ‘Public Utilities’ with the intention that this land will be ceded and vested with the Department of Lands at subdivision stage. This apporach is consistent with previous structure plans in the area, including the recently endorsed LSP1B and LSP1C structure plans.
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3403Rep7A 53 3.10 Infrastructure Coordination, Servicing and Staging
Civil engineering consultant Pritchard Francis has prepared an infrastructure servicing report in support of the LSP, refer Appendix 5. The report includes a detailed earthworks and servicing strategy, and demonstrates that coordination of, and access to essential service infrastructure is not a constraint to development. The strategy is summarised below, and is included in full as Appendix 5.
3.10.1 Earthworks
As part of subdivisional works, the LSP area will be re-contoured through a cut to fill operation and the importation of clean sand fill to maintain 1.2m clearance from the maximum groundwater level (MGL). This additional clearance removes the need for subsoil drainage, ensures that adequate flood protection is provided, and minimises the risk of exposure to acid sulphate soils.
The site preparation and earthworks will take into consideration the retention of significant trees within open space areas wherever possible, and will not include any substantial earthworks within the pipeline corridor.
A preliminary earthworks plan is Figure 18.
3.10.2 Waste Water
The LSP area has access to the existing reticulated waste water scheme via the planned type 90 waste water pumping station at Youle-Dean Road. Access to the pumping station will be provided via the extension of an external sewer main from the south, with the alignment of the extension to be confirmed in consultation with the Water Corporation as planning progresses. The extension of the sewer main to the LSP area will also allow the temporary Type 10 pump currently in use on lot 9203 to the north to be decommissioned.
Pritchard Francis will continue to work with the Water Corporation as planning progresses in order to refine the sewer design and to confirm timing and availability.
3.10.3 Water Supply
The Water Corporation has confirmed that the LSP area can be serviced by the extension of an existing 250mm water reticulation main located at the northern boundary within the Avonlee estate. A 200mm water main is proposed to extend through the LSP area, with 100mm mains to service lots.
3.10.4 Electrical Supply
The LSP has excellent access to existing Western Power transmission assets in the vicinity, including:
• Beechboro Zone Substation - approximately 10km south-west of the site; and
• Ellenbrook Zone Substation on Gnangara Road- approximately 2.5km north of the site.
Western Power has indicated that approximately 5MVA of capacity remains between the two substations however both have the opportunity for future expansion to increase future capacity if warranted. As such, development of the LSP area will not require construction of any new substations, as all demand can be met from the existing substations.
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www.cleplan.com.au
3403-33-01 (31.08.2015), Nts
This plan is an indicative land use concept depicting one hypothetical development scenario for the land and is prepared for illustrative purposes only. It has no formal endorsement or approval status. Any lot boundaries, areas, road networks, public open space or any other land use detail depicted should be considered notional and will be subject to change as part of any subsequent formal planning approval processes. This plan remains the property of CLE.
3403Rep7A 55 Access to the regional HV system is provided via the 132kV transmission lines located on the
southern verge of Woollcott Avenue. It is understood that the transmission line will remain in Woollcott Avenue for the time being, however given it is located on the southern side of Woollcott Avenue there are no implications for the LSP area.
3.10.5 Telecommunications
It is understood that the LSP area falls within NBN Co’s servicing region and there would be an opportunity for the landowners to enter into an agreement with NBN Co for the provision of NBN Co’s ‘Fibre to the Home’ (FTH) in the LSP area.
Alternatively, Telstra is another provider of communications infrastructure in the Brabham area. Either NBN or Telstra pit and pipe infrastructure will be installed as part of the subdivision works, with the preferred provider to be determined as planning progresses.
3.10.6 Gas
A proposed 160E gas main is planned for lot 9203 which will terminate at the northern boundary of LSP area. Gas reticulation will be installed as part of the common trench, following the water main from the north to the south of the LSP area.
3.10.7 Development Staging
It is anticipated that the structure plan area will be developed in stages over a period of 12-24 months. Initial stages will include key infrastructure items including access and intersections to Woollcott Avenue. A preliminary staging plan is included as Figure 19.
The provision of civil infrastructure will be staged to suit development demand and precise timing and staging of development will be confirmed at detailed design stage.