Parliamentary Committees

Public Works Committee: Morphett Vale Odour Management

Mr BROWN (Florey) (11:19): It is with great pleasure that I move:

That the 100^th report of the committee, entitled Morphett Vale Odour Management Project, be noted.

Over the last decade SA Water, also known as the agency, has received 18 complaints regarding unpleasant odours emanating from the Morphett Vale wastewater network. The agency has since identified this network, which services approximately 30,000 customers, as an odour hotspot. The proposed works will construct a new odour control unit, also known as OCU, in Morphett Vale to provide a long-term preventative solution for the local wastewater network, removing the odour source for the local community.

An investigation into the network identified a short list of options to address the problem, with the agency considering multiple options, including:

to proceed minimally as things currently stood; that is, relying on regular cleaning and the replacement of two small filters every six months;

replacing the two small filters with larger, ground-based carbon filters;

installing a ferrous chloride chemical dosing station;

installing a magnesium hydroxide liquid dosing station; or

installing an odour control unit.

After assessing these options against technical, social and environmental categories, the agency determined the construction of an OCU was the preferred intervening measure. The OCU functions by drawing in the air from the local wastewater network and treating it using various filters to allow adequate cleaning before releasing the purified air through a discharge vent stack. By constructing the unit, the agency will provide an outcome in line with SA Water's business strategy and reduce the odour to a level that meets the service requirements committed to by the Essential Services Commission of South Australia.

The OCU will also reduce levels of hydrogen sulphide gas in the sewer, lowering risks of corrosion to the sewer mains. The unit will be strategically located on a nature strip off Main South Road behind the Emu Hotel in Morphett Vale on land recently acquired by SA Water. An additional induct will be constructed in the council reserve off Barbara Avenue, which will require some enabling works to connect the OCU to the existing sewer. Construction is anticipated to commence in the first quarter of next year and is scheduled for practical completion in late 2025.

The agency expects the project to cost up to $6.6 million, with operational costs of approximately $630,000 over 30 years. Both these costs will be funded through the regulatory determination, and there will be no impact on SA Water's overall borrowings or contributions to government. The agency states that as the works are a continuation of an existing service an economic benefit cost ratio is not required, as the primary driver is not for economic benefit to the state.

SA Water utilises procurement frameworks that enable the sequential award of works, incentivising suppliers to perform well to secure future contracts. These frameworks deliver significant benefits through collaboration, innovation, consistency, planning and programming. This project has been included in the Wastewater Major Framework program, and procurement has been conducted in accordance with SA Water procedures and applicable government policies. While the option analysis and concept design was completed by SA Water engineering, a design and construct model was selected to deliver the project, and framework partner Fulton Hogan Utilities submitted a proposal.

The agency affirms the design and construct package will be awarded in accordance with SA Water's delegation of financial and procurement authority and applicable government policies. A project manager will be responsible for delivering the project in accordance with SA Water's corporate project management methodology. This project manager is accountable for the development and delivery of the overall project, including seeking the necessary approvals and management of the selected contractor and works.

SA Water uses a risk management policy to identify project risks and develop mitigation strategies. These risk management guidelines will apply over the course of the project and be undertaken on an ongoing basis. The agency has identified the following key risks:

contaminated soil, for which soil testing has been conducted, finding no exceedance of appropriate waste fill criteria;

unknown or unexpected services during construction, for which the contractor has been engaged to complete potholing to locate underground services; and

groundwater, for which a geotechnical investigation of the area has been undertaken, with no groundwater encountered.

SA Water's corporate-wide policies reinforce its business commitment to operating sustainably. The selected contractor will be encouraged to develop processes, with due regard for short and long-term, local and global, environmental, social and economic considerations, including conservation and efficient use of resources, engaging local subcontractors, reducing carbon emissions, the development of flexible processes and products, and implementing recycling and re-use.

The contractor will have an established construction and environmental management plan, and a site environmental management plan will be developed to address these specific requirements and associated approval conditions. No regulated or significant trees have been identified for removal, but some native vegetation removal will be required and SA Water states that this vegetation clearance has been granted approval.

Initial assessment indicates that the site is in proximity to sensitive noise receivers, including the Emu Hotel and residential housing, and the design will incorporate acoustic enclosures to minimise noise. Following construction, the agency will conduct noise monitoring to ensure that the site meets requirements outlined in the environmental protection policy.

The project site is within the Kaurna People Native Title Settlement Indigenous Land Use Agreement area, and SA Water states that the subject parcel of land is not identified as native title land within this agreement. The agency has identified a medium risk of impacting or encountering Aboriginal objects or remains; therefore, during construction SA Water will comply with its standard operating procedure for the discovery of Aboriginal heritage and that all on-site employees are to attend a site-specific Aboriginal cultural heritage induction. If any Aboriginal sites or objects are found, work should cease immediately, and an Aboriginal heritage and engagement advisor be contacted. SA Water's environment and heritage expertise has identified no European heritage items on the site.

The agency has appointed a dedicated stakeholder management representative to keep all relevant stakeholders informed regarding project developments. Consultation with local council has not raised any issues or concerns. SA Water is also in consultation with the Department for Infrastructure and Transport and the City of Onkaparinga regarding the potential need of a traffic management plan. An internal property, planning and environmental team has confirmed no development approval is required. The project submission has been circulated with relevant government departments that have indicated broad support for the project.

The committee has examined written and oral evidence in relation to the Morphett Vale Odour Management Project. Witnesses who appeared before the committee were: Peter Seltsikas, Senior Manager, Capital Delivery, SA Water, and Tracy Buchanan, Project Manager, SA Water. I thank the witnesses for their time.

Based upon the evidence considered, and pursuant to section 12C of the Parliamentary Committees Act 1991, the Public Works Committee reports to parliament that it recommends the proposed public work.

Motion carried.