Mundaring Water Treatment Plant, Australia
Key Data
Mundaring Water Treatment Plant (WTP) is a A$300m public private partnership (PPP) project being undertaken in Mundaring, a residential district located approximately 21 miles east of Perth, in Western Australia.
The project will secure long-term water supply for Wheatbelt and Goldfields regions of the state. The eastern metropolitan hill suburbs will also benefit from the project.
The plant will have an ultimate capacity of about 240,000 cubic meters a day, but will initially be outfitted for 165,000 cubic meters each day.
Construction on the project began in the second half of 2011 and the plant is scheduled to commence operations in July 2013.
Water Corporation, the main supplier of water, wastewater and drainage services in Western Australia, is the project proponent and is also acting as the project manager.
Mundaring WTP project components
The plant is being constructed on the Mundaring Weir Road at a redeveloped 136,000m² site which was previously occupied by the Department of Environment and Conservation (DEC) depot building.
The DEC depot building was relocated to the southern portion of the site in September 2011.
In addition to the WTP, the project comprises construction of a third pump station (C Pump Station) at Mundaring Weir and two pipeline corridors (one to connect the C Pump Station to the existing A Pump Station, with another one to connect the WTP to the existing pipelines). Off-site and on-site are the other two components of the project.
Treatment facilities will include pre-treatment, filtration, chlorination, stabilisation and fluoridation.
The C Pump Station will have an initial capacity of 165,000 cubic meters a day. It will be located between pump stations A and B below the weir and construction will take place between 2011 and 2013. The existing two pump stations, a substation and chlorination facility will be decommissioned in 2014 under a separate project.
Purpose of the PPP project
Mundaring WTP project is an important component of the Mundaring Weir water supply improvement project (MWWSIP) which comprises construction of a number of new assets and upgrades to the existing assets at or near the weir.
The Mundaring Weir was built more than 110 years ago over the Helena River and since then it has been the primary source of water for the Goldfields and Agricultural Water Supply (GAWS) scheme which supplies water to more than 100,000 inhabitants from Mundaring to Kalgoorlie.
In spite of several upgrades to the weir and its associated infrastructure, parts of the facility are not able to sustain increasing water demands and current Australian drinking water guidelines. Aesthetic water qualities such as colour, taste and odour have also deteriorated over the years.
Water supplied from the weir is disinfected but is not filtered as yet. The new WTP will bring in filtration processes and will treat the entire water from Mundaring Weir prior to disinfection.
Apart from the WTP project, the MWWSIP also involves the upgrades of weir wall outlets and electrical power, improvements to the precinct and public facilities for city denizens and tourists, plus relocation of the DEC's Perth Hills District office.
Key players involved with the Australian water treatment plant and financing
In February 2011, Helena Water consortium, comprising the Royal Bank of Scotland, Acciona Agua, United Utilities and Brookfield Multiplex, was chosen to finance, design, construct and operate the new WTP for 35 years.
The contract was signed between Water Corporation and the consortium in July 2011.
Most of the civil and electro-mechanical work will be carried out by Brookfield Multiplex. The design, construction management and commissioning are the responsibility of Acciona and Trility. The two companies will also operate the plant under a 50-50 joint venture.
APP-Hyder joint venture has been roped in to act as independent certifier and independent reviewer of the WTP project.
Water Corporation was advised on the PPP by Corrs Chambers Westgarth, a law firm based in Australia.
The project reached financial closure in July 2011. Approximately A$255m of the total funding package of A$300m will be provided by the Bank of Tokyo-Mitsubishi UFJ (BTMU), Banco Bilbao Vizcaya Argentaria (BBVA), BNP Paribas and WestLB in the form of a seven-year syndicated loan.
The remaining amount will be paid in the form of equity divided amongst Acciona Agua (25.05%), Trility (25.05%) and Lloyds TSB's infrastructure fund Uberior Investments (49.9%).
