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It is the SETS Group's firm belief that Western Power’s preferred site for the Eastern Terminal substation is in Hackett’s Gully, in state forest east of Kalamunda. This is based on our research into the 18 year history of the Eastern Terminal, from which the quotes that follow are drawn.

If you have read the History of Hackett’s Gully and Western Power you will know that in June 2007, Western Power representatives informed Hacketts Gully residents that the  Eastern Terminal development was going ahead in Hacketts Gully.  Residents were also provided with a map on which the preferred site in Hacketts Gully was marked.

Following this meeting with Hacketts Gully residents, in September 2007 Western Power sought the assistance of the broader community with the selection of a site.  It is difficult to understand why Western Power adopted this sequence of steps, particularly as on 9 May 2002 Western Power wrote to Hacketts Gully residents to inform them that the Eastern Terminal would not be built on the site first chosen in Hacketts Gully, and that “we also have no intention to acquire an alternative site in areas close to Hacketts Gully as previously stated”.

Reasons Western Power rejects OTHER site options within the study area:

10/08/92 – Letter from SECWA to Kalamunda Shire, in relation to potential sites east of Hacketts Gully, and further south at Victoria Reservoir and Douglas Road:

• The Victoria Reservoir and Douglas Road sites, although slightly more desirable in respect to visual impact, are less desirable environmentally and in suitability for the intended purpose than the preferred site.
• …neither site [Victoria Reservoir and Douglas Road] has any 132 kV lines in the vicinity.  To supply power to the metropolitan 132 kV grid new 132 kV lines would have to be built down the Darling Scarp to Cannington and Gosnells and along the escarpment to Kalamunda.
• These new lines would have significant social and environmental impact and render the Southern [Victoria Reservoir and Douglas Road] sites less desirable than Hackett’s Gully.
• The substation could be moved further East [from Hacketts Gully] but at substantial extra cost due to the extra line lengths involved.
• [Referring to the existing lines in Hackett’s Gully] These lines would have to be extended and routed in a wide corridor to a substation located further to the East.

 19/10/92 – Letter from SECWA to Kalamunda Shire

Your suggested site to the east of Mt.Gungin is certainly a possible location for our Eastern Terminal Substation.  A substation at Mt. Gungin would be located well away from residents; however at this point in time we think it would be disadvantaged by the conglomeration of transmission lines needed to interconnect it with the transmission system.  It would also be less functional and more expensive because of the greater distance from the load it would serve.

30/08/99 – Stakeholders Meeting, Discussion Paper by Western Power

The viable alternative site location would need to be reasonably close to the existing transmission lines in the area and less than 10km from Canning Location 3897 [Hackett’s Gully].  More distant sites would require an unacceptable level of clearing for new transmission line corridors.

Reasons why Western Power prefers Hacketts Gully:

10/08/92 – Letter from SECWA to Kalamunda Shire

• The preferred site is in Hackett’s Gully.
• The preferred site has been chosen because of the conjunction of existing 132 kV and 330 kV power lines near the site.
• From an environmental viewpoint the preferred location is desirable because it does not create any new edge effects, being located between the existing line corridor and the orchards.
• Also this site has a big advantage in that with the exception of a possible line going East, foreseeable transmission line developments associated with the substation can be located in existing corridors.

07/09/92 – Letter from SECWA to Kalamunda Shire

It is expected that a substation at the Hackett’s Gully site would not be a prominent feature of the viewshed as it would only be partly visible from vantage points a few kilometres away.  The most visible aspect would be the tops of the (approximately 6) additional 330kV transmission line towers needed for the cut-in of the existing line and these can be painted green.  We do not expect the site to be visible from the road or from nearby properties.

07/09/92 – Shire of Kalamunda (Planning & Building Services Committee Minutes) on SECWA’s report ESD 53/92 July 1992 “Eastern Terminal Substation – Site Selection Report” by Bowman Bishaw Gorham

• The preferred site is located within State Forest, the immediate north east of the orchard properties in the Bahen Road area, and south of Mundaring Weir Road.
• The preferred option involves no new transmission line routes through the escarpment, but future upgradings on existing routes within the Hills area as shown on the plan.
• This substation proposal will initially improve the interconnection of the existing 330kV and 132kV networks and ultimately provide a connection point for future power stations.

19/10/92 – Letter from SECWA to Kalamunda Shire

Our preferred site in Hackett’s Gully is seen at present to be the best option in terms of the environmental, social, engineering and economic considerations.  The major determining factor has been the perceived impact of interconnecting transmission lines on the environment.  We strongly believe that the Hackett’s Gully site is superior to the other sites in this respect.

15/03/99 – Letter from Western Power to Hon Derrick Tomlinson MLC

It is true that one of the sites under consideration is immediately to the north of the site described as Option 1 . . ..” [in Hacketts Gully]

30/08/99 – Stakeholders Meeting, Discussion Paper by Western Power

• The reasons for selecting this study area [in Hacketts Gully] were: the need to avoid impacts on urban areas and to avoid the conflicts likely to arise from urban encroachment; proximity to existing 66 kV, 132 kV and 330 kV transmission lines; and proximity to load.
• The Hackett’s Gully Area was the favoured choice from the study because the existing line corridors in the area meant that a site could be developed with less clearing than other potential sites.

Recent statements by Western Power and their consultants:

04/09/07 – Sinclair Knight Merz, Due Diligence Review of 330kV Augmentation Studies

1.1 Project Background

In their report New Large Network Asset 330 kV Transmission Line to support Electricity load in the Perth metropolitan area  Western Power have described the need to establish a new 330 kV network augmentation to facilitate the secure supply of electricity to demand centres in the South West Interconnected System (SWIS).

Western Power has identified two main options that have been considered for the new transmission line route:

 (1) From Landwehr Terminal (in the Wagerup area) to a new 330 kV switching station known as South East terminal (in the Oldbury area); and

(2) From Shotts Terminal at Collie via Wells terminal (adjacent to the Boddington Gold Mine) to a new 330 kV switching station known as Eastern Terminal (in the Hackett’s Gully area).

23/02/08 – Letter to  Hills Gazette from Mr Mark de Laeter, General Manager, Customer Services, Western Power  (“Home not yet chosen for ET”):

I assure the residents that Western Power has not chosen a location for the proposed Eastern Terminal (ET) substation.

October 07 - Echo, “Substation site up for discussion” , Mr Adrian Stubbings, Project Officer, Western Power was quoted as stating:

• Referring to the community workshops Western Power held on the 22, 23, 24 October 2007:

"The site will be determined out of the workshops.”   

"Western Power was taking a new look at the site selection process after deciding against developing another site in the area it had earmarked during the 1990’s."

February 2008 Site Inspection by SETS Group members.

In February 2008 the site shown on the map provided to Hacketts Gully residents in mid-2007 was inspected by members of the SETS Group.  This is “site 2”.  Site 2 had been selected by Western Power in 1999 as an alternative to the original site.  It is slightly to the north of the original site and closer to Mundaring Weir Rd.

During the inspection, surveyors tape and metal tags were observed.  The tags were marked “Glevan;  WP”; and dated 28/8/07.  Glevan Consultancy Services subsequently confirmed that they had conducted a Phytophthora dieback survey on behalf of Western Power on 28/8/07.

Western Power representatives met with Hacketts Gully residents and SETS Group members on 13 February 2008.  Subsequently, written confirmation of points made in the meeting was requested, including comment on the following:

The residents again reminded you of a letter they had received on 9 May 2002 from Western Power stating:  Following a review of the long term electrical load requirements for the east metropolitan area, we wish to advise that a terminal substation will no longer be required at Location 3897 Mundaring Weir Road, Hacketts Gully.  We also have no intention to acquire an alternative site in areas close to Hacketts Gully as previously advised.

In an email dated 27 February, Mr Adrian Stubbings, Project Manager, responded:

"Western Power again acknowledges that the letter was written, we are currently looking at adding a 1km buffer to all private property in the study area, in which the site will not be located." 

The site inspected by SETS Group members is slightly over one km from private property.  It is clearly within Hacketts Gully.

In an email dated 6 March 08, Mr Adrian Stubbings further advised:

"We are now looking into the possibility of a 500m or 750m buffer and the clearing impact that may arise as a result."

For the purpose of considering the potential impacts of an Eastern Terminal, the SETS Group believes it is necessary to assume site 2 is the preferred site – even though Western Power denies they have a preferred site.  The environmental and other characteristics of site 2 are virtually identical to the original site 1, which was rejected as being unsuitable by Western Power in 1999.  However, as site 2 is more elevated, its visual impact would be substantially more intrusive.

The SETS Group believes site 2 to be the preferred site.

We believe that the preferred site has always been in Hacketts Gully.   Is it just a coincidence that the existing 330 kV power line that runs through the Piesse Brook valley “dog legs” up to the Hackett’s Gully area, for no apparent reason?