50 Years - 50 Stories: Picnic Bay Membrane Bioreactor STP - A first for Picnic Bay (and Australia!)

Greg M Johnston (in Ipswich, Queensland) on phone to Geoff Parker (in Sydney, New South Wales) sometime in the year 2001:

Greg M Johnston – “g’day Parker, Greg here”

Geoff Parker – “g’day Greg”

Greg M Johnston – “Parker, we’ve won an MBR contract for Picnic Bay and I want you to manage it”

Geoff Parker – “OK, what’s MBR stand for, and where’s Picnic Bay?”

Greg M Johnston (long pause) – “Parker, best get your *** up here tomorrow...”

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Picnic Bay’s Membrane Bioreactor (MBR) Sewage Treatment Plant (STP) was built for Citiwater (a business unit of Townsville City Council) and located on Magnetic Island. Magnetic Island is a 52 km² mountainous island located 8 kilometres offshore from the city of Townsville with a population of approximately 2,100 people. Picnic Bay's MBR was designed late in 2001 and built and commissioned in 2002. Winning the job was significant as it was to be Australia’s first full size tertiary membrane STP. The contract was won by Paul Kwong despite stiff competition from a more favoured opposition company. The MBR process was chosen due to the need to meet the strict environmental discharge requirements set by the Great Barrier Reef Marine Park Authority. Treated effluent was then to be discharged either to the Coral Sea during the annual wet period or diverted to the local golf course in the dry months.

Membranes were of the flat plate type, supplied by Kubota. The primary treatment consisted of a Noggerath multi-purpose screen, followed by a balance tank and secondary aeration – provided by fine bubble submerged Aquablades. The plant design and material selection needed to consider the humid cyclonic climatic conditions, as well as the requirement to minimise underground piping and electrics to counter rodent damage. During the design stage which involved familiarisation with the MBR specifics along with standard mechanicals, aeration, tankage, and plant control design, a young engineer, Peter Ferrando, was seconded to the design team; Peter must have really enjoyed being in charge, because he’s now the Managing Director of the Aquatec Maxcon Group!

Following a relatively straightforward commissioning, the plant readily met all the performance guarantees, however the longer term irony was that the golf course had to ship over nitrogen and phosphorus based fertilisers to spread on the areas sprayed with the treated effluent as the nutrients having been (a bit too successfully?) removed by the MBR process.

As a final testament to the success of the plant, Citiwater won an environmental award in 2003 for the "Magnetic Island Water Recycling" (MIWR) project. Please click here for the full featured article from "Engineers Australia" published in September 2003.

Moving forward - In 2006 (as part of the Water Matters Alliance) -  Aquatec Maxcon carried out installation of the second Kubota MBR train, thus bringing the plant to full capacity. We also carried out a sheet-by-sheet inspection and the cleaning of the existing MBR to evaluate the performance of the Kubota membranes. The plant capacity had not been impacted despite the membranes being more than halfway through their design life. It was a fantastic opportunity to be able to return to the plant and see it outperforming all expectations since it was built almost 20 years ago back in 2002.

Above and below: Picnic Bay's brand new Membrane Bioreactor Sewage Treatment Plant, circa 2002. Photos from Geoff Parker's private collection.

Above: Views from Magnetic Island.. Photo from Geoff Parker's private collection.