The EMRC has written to member Councils seeking advice on this proposal.

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1 4.1 WASTEWATER TREATMENT FACILITY - RED HILL (Gidgegannup) (Operations) KEY ISSUES The EMRC has been approached to sell or lease an area of land at its Red Hill waste treatment facility for the establishment of a wastewater treatment plant. The EMRC has written to member Councils seeking advice on this proposal. The proposal would provide a source of treated effluent for use by the EMRC and would negate the need to construct additional water storage on site at an estimated cost of $1 million. The proposal includes provision for supplying treated effluent to the Swan Valley for irrigation purposes. Locating a wastewater treatment plant at Red Hill may result in negative environmental and social implications for the EMRC and the City of Swan. A report on this matter was considered at the OMC on 30 April 2008 when it was resolved to obtain feedback on the matter from the Swan Valley Planning Committee on the potential demand for treated effluent in the Swan Valley. The matter was considered by the Swan Valley Planning Committee and resolved that grape growers in the area may accept the treated effluent if the water was able to be provided at an economically viable cost, volume and seasonal usage requirements. It is recommended that the EMRC be advised that the City does not support the sale or lease of land for the purpose of constructing a wastewater treatment plant at Red Hill at this stage. It is also recommended that the EMRC be advised of the City's concerns such as the viability of piping treated effluent to the Swan Valley in terms of costs to end users, available volumes and seasonal variances of the treated effluent; the practicality of storing treated effluent in the Herne Hill quarry; the management of sewage spills; amenity of surrounding land use; odour issues and the potential negative impacts being linked to the EMRC's Red Hill facility. BACKGROUND The City has received a letter from the EMRC seeking advice on a request that the EMRC has received regarding the possibility of establishing a wastewater treatment plant (WWTP) at the Red Hill waste management facility. The WWTP would service urban developments in Stoneville and Parkerville within the Shire of Mundaring. The EMRC has commissioned a consultant to assess the advantages and disadvantages of the proposal from the EMRC's perspective. At the EMRC meeting of 13 December 2007 it was resolved that: Page 1

2 1. The EMRC not develop a waste water treatment plant at Red Hill waste management facility. 2. The EMRC enter into negotiations with Water Corporation to lease land for the purposes of establishing a waste water treatment plant at the Red Hill waste management facility 3. The EMRC consult with member Councils in relation to the possibility of selling/leasing a portion of land to Water Corporation for the purposes of developing a waste water treatment plant. A Council Briefing Session on this matter was held on 2 April 2008 at which information was presented by representatives of both the EMRC and Greg Rowe and Associates. The matter was considered at the Ordinary Meeting of Council on 30 April 2008 at which it was resolved that Council: 1. Refer the matter to the Swan Valley Planning Committee for comment. 2. Record that the reason for changing the Recommendation is to obtain feedback on the potential demand for treated effluent in the Swan Valley. The matter was referred to the Swan Valley Planning Committee and considered at the meeting of 26 May 2008 at which it was resolved: To advise the City of Swan Council, that grape growers in the Swan Valley may accept the water through this facility, if the water was able to be provided at an economically viable cost, volume and seasonal usage requirements. REPORT In mid 2007 the EMRC received a request from Greg Rowe and Associates regarding the possibility of establishing a WWTP at Red Hill waste management facility. The request was on behalf of the owners of proposed urban developments in Stoneville and Parkerville within the Shire of Mundaring. The EMRC awarded a consultancy to URS Corporation to review the advantages and disadvantages of the proposal. As part of this consultancy study two meetings were held with the Red Hill Community Liaison Group. The WWTP project has the potential to generate water for use at the Red Hill waste management facility. At present this facility uses approximately 6 million litres per year (6ML/yr). This amount increases to 30ML/yr during landfill construction. The EMRC is considering developing a Resource Recovery Facility at this site which would require approximately 50ML of water per year. Thus the total water requirements by the EMRC at this site would be up to 80ML/yr. Water for this facility is currently supplied from Midland Brick water storages which are insecure and unreliable in the long term. The development of a secure water source on site to supply the maximum water requirements would cover an area of approximately 2.7 hectares and cost in the order of $1 million to construct. The WWTP is anticipated to require an area of one hectare and generate up to 1,050 ML per year of treated effluent. The EMRC facility would only require a small amount of this effluent so it has been proposed to pipe the remaining effluent to the Swan Valley for irrigation. This proposal would include storage of effluent in Hanson's abandoned Herne Hill quarry. Page 2

3 The biosolids generated at the WWTP have been estimated at 440 wet tonnes per year and could be handled through composting and blending at Red Hill to generate a product for sale. The EMRC has identified land that may be considered suitable for a WWTP at the Red Hill site. It is located to the north of the proposed Perth-Adelaide Highway so would be separated from the remainder of the Red Hill site. Information supplied by the EMRC summarises the advantages and disadvantages of the proposal as follows: Environmental Social Financial Advantages Enables environmentally sound treatment of effluent Enables progression of some currently stalled land developments Earns EMRC money from sale of land and disposal of biosolids Provides secure source of water for Red Hill Potentially provides security of water supply for Swan Valley irrigators Saves costs of development of water storage dam Enables the development of a WWTP outside the John Forrest National Park catchment Disadvantages Potential odour impacts Potential night time noise impacts Potential sewage spills into Strelly Brook Catchment Significant public opposition to development in Perth Hills may impact on EMRC Negative environmental impacts associated with WWTP may be connected to Red Hill If Red Hill were closed, the member Councils may have a short-term problem of accumulating waste May need to pay for water from WWTP Closure of Red Hill would have substantial impacts on EMRC and member Council viability It should be noted that if the WWTP were located at a site other than Red Hill then it may still be possible for the EMRC to have access to treated effluent. The cost of this option would depend on the location of the main pipe but would be approximately $50,000 if the pipe was located along Toodyay Road and an extra $500/m for additional distances. The potential environmental impacts such as night time noise, sewage overflows and odour can be addressed according to the report from URS Corporation. These issues can be Page 3

4 addressed by having a 400m buffer to control the impacts of odour and ensuring housing is not located near the WWTP. There is potential for a sewage overflow into Strelly Brook catchment. However, the URS Corporation report indicates that the alternative sites for the WWTP (within the Shire of Mundaring) could result in sewage overflows into John Forrest National Park. The EMRC has also identified that the consolidation of waste treatment facilities in one area could cause community concern due to the concentration of environmental impacts. However, it could also be argued that such a consolidation would reduce the area subject to these risks. It is likely that residents near the facility may resent the fact that wastewater from developments in other areas is being transferred and treated near them. While the EMRC has also asked for advice on the option of leasing land, it should be noted that the Water Corporation have indicated that it will only construct a WWTP on land that it owns to ensure security of tenure. Consequently the option of leasing land is unlikely to be a viable alternative. There are a considerable number of approvals that would be required to be obtained for the project to result in treated effluent being made available for use in the Swan Valley. These would include environmental approvals, financial feasibility studies, health approvals and planning approvals. Consequently the sale of the land to the Water Corporation would not guarantee that the project would be able to be implemented, or in what form it would be implemented. The advice from the Swan Valley Planning Committee indicated "that grape growers in the Swan Valley may accept the water through this facility, if the water was able to be provided at an economically viable cost, volume and seasonal usage requirements". While this advice confirms that there may be a demand for the treated effluent, it also confirms that further work would be required in the areas of costing, volumes and seasonal variances. At this stage the EMRC has asked member Councils for advice on the proposal. While the proposal has merit, there are also a range of issues that are unresolved and would require considerable work to satisfy the City that the proposal to sell land should be supported. These include factors such as the viability of piping treated effluent to the Swan Valley and the associated costs to end users, the available volumes and seasonal variances of the treated effluent, the practicality of storing treated effluent in the Herne Hill quarry, the management of sewage spills, amenity of surrounding land use, odour issues and the potential negative impact being linked to the EMRC's Red Hill facility. It should be noted that if these issues are not resolved prior to the sale of the land then the City would not be the approving authority for many of these matters. Consequently if the City supports the sale of land by the EMRC at this stage then the WWTP may be constructed without the issues of concern being addressed to the City's satisfaction. ATTACHMENTS Nil STRATEGIC IMPLICATIONS Waste management is undertaken in accordance with KRA 3 in the City's Strategic Plan. A decision to sell or lease land for construction of a WWTP would have significant impact on the local community. Page 4

5 STATUTORY ENVIRONMENT At this stage the EMRC has only asked for advice on the proposal to sell or lease land for a WWTP. In the event that the proposal progressed then there would be a range of statutory approvals that would be required to be obtained. FINANCIAL IMPLICATIONS The City would indirectly benefit financially through the financial benefits to the EMRC including the revenue from the sale of land and the saving from not having to construct water storage at the waste treatment facility. RECOMMENDATION That the Council resolve to: 1) Advise the EMRC that it does not support the sale or lease of land for the purpose of constructing a wastewater treatment plant at Red Hill at this stage. 2) Further advise the EMRC that the City's concerns with the proposal include uncertainty about factors such as the viability of piping treated effluent to the Swan Valley in terms of costs to end users, available volumes and seasonal variances of the treated effluent; the practicality of storing treated effluent in the Herne Hill quarry; the management of sewage spills; amenity of surrounding land use; odour issues and the potential negative impacts being linked to the EMRC's Red Hill facility. CARRIED Page 5