douglas north substation project

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Visual Impact StudyVisual Impact StudyVisual Impact StudyVisual Impact Study

Douglas North Douglas North Douglas North Douglas North

Substation Project Substation Project Substation Project Substation Project

Douglas Park NSW

BHP BILLITON ILLAWARRA COAL

9 February 2007

Prepared by:

Douglas North 66/11kV Substation Project - Visual Impact Study - 9 February 2007 Page 1

Figure 1 Location Map showing the proposed Douglas North 66/11kV Substation and Prices Road Switching Station locations; and the Power Line Route.


Douglas North 66/11kV Substation Project Visual Impact Study Introduction This study was commissioned to assess the visual impact of the proposed Douglas North 66/11kV Substation and associated new power lines and power poles at Douglas Park NSW. Background The Douglas underground coal mining operations require an 11 kilovolt electricity supply to power machinery and lighting to the mine approximately 450 metres below ground. In order to achieve this, BHP Billiton – Illawarra Coal proposes to source electricity from the Integral Energy 66 kilovolt main (“Feeder 850”) via the Prices Road Switching Station and transmit this power to a proposed new Electrical Substation (approximately one kilometre to the northeast) in Moreton Park Road, Douglas Park. For practical reasons, electricity is readily transmitted at high voltages (in this case 66 kilovolts) over long distances and is then transformed down into lower voltages (in this case 11 kilovolts) at a substation, closer to the point where the electricity is required. Location and Setting Douglas Park is a small township in a rural area of mostly open countryside with outlying farms. The countryside is dotted with houses, agricultural buildings and large fabric covered greenhouses. The district is bisected by the dual carriageway of the Hume Highway and the Main Southern Railway line. The Nepean River passes about 1.5 kilometres southeast of the town where it is joined by the Cataract River – both rivers flowing through deeply cut gorges. The area is identified as part of the South Campbelltown Mine Subsidence District because of the long history of coal mining carried out deep below the surface. The Prices Road Switching Station is part of the Integral Energy 66kV power distribution network and is located 250 metres to the south east of the Hume Highway at Douglas Park; about 1.0 km south east of the Douglas Park township. (See Figure 2)


Description of Proposed Works It is proposed that power is taken from the Prices Road Switching Station and transmitted at 66 kilovolts via aerial power lines supported on concrete poles along an existing electrical power corridor (in a northeasterly direction for a distance of approximately 1 kilometre) to a proposed new electrical substation in Moreton Park Road. At the new substation the power will be transformed down to 11 kilovolts and then fed along a buried power cable for approximately 100 metres. This 11 kilovolt cable would then travel down into the ground through bore holes to the coal mining operations approximately 450 metres below the ground surface. There are a number of Visual Impact issues to consider which arise from the construction of the above:

• Opportunities for landscaping new works • Industrial appearance of electrical substations

• General visual impact of the new power lines and power poles replacing the current

poles and lines along the existing power line corridor (between the switching station and the proposed substation).

• General visual impact of the proposed substation in Moreton Park Road.

• Visual impact of the works viewed from the Hume Highway

• Potential loss of vegetation The most significant structures of a Substation Station are: power poles, aerial conductors, insulators, high voltage switching steel framework, lightning protection masts, switch gear, voltage transformers and associated electrical handling gear, a control room and security fence. (See Figure 6) Traditionally power poles were timber but now concrete power poles are used because of inherent strength, durability and termite resistance. They are typically 18 – 20 metres high, located approximately 100 metres apart and support 3 conducting cables for either the 66kV or 11kV supplies. The conducting cables are attached to the poles with ceramic insulators. (See Figure 10)


General Observations Electrical Substations have an industrial appearance. However the steel work is usually galvanized and the equipment is generally grey in colour which is a neutral colour that blends reasonably well into the environment. Substations have control buildings containing electrical control equipment and are typically constructed of brick, concrete block or steel framed with metal cladding and steel sheet roofing. In this proposal the control building will be lightweight with metal clad walls and roof. Perimeter fencing is either galvanized finished or painted (usually black). Perimeter fencing was formerly cyclone wire (galvanized finish) with strands of barb wire above. However changes to safety requirements now demand fencing which is less penetrable to trespassers because of dangerous voltages within. Integral Energy has adopted a new standard fence. (See Figure 9) The choice of colour for the fence is important as a dark neutral dark colour will improve the transparency of the fence and consequently reduce its visual impact. Concrete power poles are grey in colour and age over time which renders them less conspicuous against a background of trees. Comments Opportunities for Landscaping Landscaping can provide useful screening and trees as a backdrop can reduce the harsh appearance of electrical stations. However because of very high voltages transmitted, trees need to be kept clear of power lines to prevent ‘flash down’ (short circuiting) and subsequent electrical danger to the public. Also trees in close proximity to electrical installations create maintenance issues and a pose bush fire risk. However, consideration should be given to exploring all available opportunities for landscaping the proposed works where practical. Industrial Appearance The utilitarian function of, electrical clearances required and serviceability of substations, power lines and poles leave little scope for visual improvement. However as noted above the colours of equipment, power poles and steel supporting structures are generally neutral in colour and skeletal, and this helps render the facilities less prominent in the landscape. Visual impact of the new power lines and power poles along existing corridor The corridor was cleared of vegetation when the existing power line and poles were established at least 40 years ago. It is considered there would be no additional visual impact arising from the proposed new poles and lines replacing the existing along this corridor. Visual impact of the proposed substation in Moreton Park Road The new substation will be visible from the Hume Highway in glimpses through the vegetation from a moving vehicle. There are Wattle trees (Acacia sp) planted in a 1.5 to 2 metre high mound along the side of the highway and this provides a good screen except for number of small breaks in the vegetation that will allow the substation to be noticeable.


Because of the degree of roadside screening it is considered that the substation will not be visually intrusive when viewed from the highway. The proposed substation site has a extensive backdrop of trees to the south and east; and a copse of screening trees (Casuarina sp) at the north boundary close to Moreton Park Road. Viewed from Moreton Park Road the proposed substation will be noticeable and distinct but sit relatively unobtrusively in the landscape. Potential loss of vegetation Trees are visually pleasing and provide screening for visually intrusive structures. They take years to establish and should only be removed where necessary. The construction of the proposed substation and outgoing 11kV line and substation access road will necessitate the removal of a number of trees and shrubs. (See also ”Opportunites For Landscaping” comments above). However there will be no loss of trees along the existing one kilometre long powerline corridor or resulting from the extensions to the Prices Road Switching Station. Recommendations To reduce the visual impact and blend the new Substation into the background the following measures are recommended:

• The perimeter security fences to the new Substation should be coloured as follows: Charcoal or black - matt finish

• Roof of control buildings above to be clad in colour: equal to Colorbond “Windspray” (grey) or “Wilderness” (grey green)

• Metal wall cladding colour of control buildings: equal to Colorbond “Windspray” (grey) or “Wilderness” (grey green)

• Power poles should be left natural concrete finish.

• Align the proposed access road where possible to retain mature trees.


Summary The proposed Douglas North Substation is reasonably well located as it mostly screened by the roadside mound and vegetation along the Hume Highway. The proposed new power line and poles along the corridor is not noticeable from the Hume Highway and its impact considered unchanged from existing. Given the existing circumstances above and by adopting this report’s recommendations, it is not likely that the proposed new Substation, power lines and power poles would be greatly noticeable or offensive to a general member of the public when viewed from the surrounding public areas. Maurice Hayler Architect NSW Architects Registration Board No. 5198 February 2007


Figure 2 Aerial Photo showing the proposed Douglas North Substation and Prices Road Switching Station locations; and the Power Line Route.


Figure 3 Aerial Photo showing closer view of the proposed new Douglas North Substation and part of the Power Line Route.


Figure 4 Photograph of existing view of the Douglas North Substation site viewed from Hume Highway. Camera zoomed 5x, equal to 135 mm telephoto lens)

Figure 5 Artists Impression of proposed Douglas North Substation as viewed from Hume Highway. (Camera zoomed 5x, equal to 135 mm telephoto lens)


Figure 6 - 3D computer model of layout of the proposed Douglas North Substation


Figure 8 Photomontage of above photo showing proposed new concrete power poles

Figure 7 Photo looking south west from Substation site showing existing powerline corridor


Figure 9 Photo showing Integral Energy security fence which replaces formerly used cyclone fire fencing. (Substation in Wollongong)


Figure 10 Photograph shows existing concrete power poles at Appin. The proposed power poles will be similar in appearance. Poles are typically located 100 metres apart.

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