The water industry has lacked a system for recording plant performance data conducted and water quality sampled by Operators. Ten years ago Wannon Water and Goulburn Valley Water combined to address this issue, however the vendor was based overseas, the system was quite complex and the lack of sufficient resources by both water corporations meant the technology was outdated before the system was fully built.

-Close

Thermal stratification in water bodies is a major factor that creates a favourable environment for infestations of algal and aquatic weed species. Infestations of algal and aquatic weed species place limitations on the operational integrity and the aesthetic value of a water body. Thermal stratification can be overcome via the introduction of aerators and/or water circulators. The aim of the project was to develop a system that would be capable of generating enough solar power to run an Acqua & Co Brio 1.0T aerator/water circulator during winter, for at least 6 hours per day, at an average efficiency of at least 85% of a conventionally powered unit while circulating 1 Megalitre per hour. Solar power, aeration and circulation.

-Close

It was out with the old and in with the new when Young Shire Council recently completed an upgrade to its Sewage Treatment Plant (STP). It was back in 2007 when Council initiated the process to upgrade the STP with a draft concept design. After five years of consultation with NSW Public Works the final design was accepted in January 2012 for the treatment works and February for the recycled water scheme (RWS). Council was granted funding of $1.5M for the RWS by the Federal Government under the Strengthening the Basin Communities program and a 25% subsidy from the NSW Government under the Country Town Water Supply and Sewerage Program.

-Close

Explores the thought that we in the water industry have overlooked our potable water networks for far too long and are now starting to feel the effects of up to two decades of neglect. Outline the work undertaken in a five-week water main cleaning program during July & August 2013 in the Southern Highlands of NSW.

-Close

The Hastings District Water Supply Augmentation Scheme has been developed to cater for future urban population growth over the next 30 years within the Port Macquarie-Hastings local government area. The associated water supply infrastructure works have included several large trunk mains and reservoirs. The New Bonny Hills Reservoir has a capacity of 13ML and will ultimately operate as both a balance tank on a major trunk main network and also as a local supply reservoir to service the daily water supply needs in the Lake Cathie and Bonny Hills urban areas. Port Macquarie-Hastings Council (PMHC) has recently implemented a reservoir dosing and mixing system to improve the quality of water stored within the reservoir and to provide a dosing injection point for the addition of chlorine and carbon dioxide gas. Reservoir dosing and mixing, water quality and maintaining residual chlorine.

-Close

Wattle Park Pumping Station is a located adjacent to an 84 Megalitre reservoir and supplies drinking water to Eastern Adelaide. Wattle Park PS is owned by South Australian Water (SAW) and operated by Allwater. Part of a recent upgrade to the Wattle Park PS involved providing rechlorination systems at the facility. After listening to the concerns of local residents, SAW decided to install Chlorination facilities that did not utilise Chlorine gas. SAW considered both bulk Sodium hypochlorite and OSEC® and eventually gave the go ahead for duty / standby electrolysers to be installed inside the Wattle Park facility.

OSEC® systems generate a 0.8% solution of Sodium hypochlorite by electrolysing a low strength brine solution. The OSEC® system requires storage of salt in a salt saturator, which provides a brine solution. Water softeners ensure that the feed water to the OSEC® system is free from any hardness. Both the brine and the softened water are fed to the OSEC® at 3% brine solution and electrolysed in the generator. Inside the generator, Chlorine and Hydrogen are liberated at the anodes and at the same time Sodium hydroxide is produced at the cathodes. The Chlorine and Sodium hydroxide then mix to form Sodium hypochlorite.

-Close

A new hospital was being built in Orange and discussions were raised regarding the requirement to install a decay holding tank for radioactive wastes potentially being discharged to sewer. The immediate response was to set up procedures including exclusion zones and restricted areas to limit access to areas of potential risk. Subsequent literature reviews and consultation with regulators and professionals in the industry, determined the risk to operators to be minimal.

To validate findings of the desk-top study, possible areas of risk were monitored through various programs around the WWTP and of the reticulation downstream of the existing hospital. Exposure levels for Council staff at the WWTP were found to be no different to background levels. Doses above background radiation levels were recorded within the sewer reticulation, although all locations monitored were below the legislated annual dose of <1000 microsieverts per annum (µSv/annum) for the general public.

-Close

Aged infrastructure and a lack of substantial income is one of the biggest single problems faced by most western NSW Councils. A decade long drought and constant reduction in available income has meant that Engineers and Operators all over the state have had to find innovative ways to extend the life of water and sewage plants while increasing the quality of product produced to comply with higher standards.

-Close

Tank design has changed significantly throughout the past 20 years. With heightened water quality standards, we have seen the introduction of roofed reservoirs, improved security and more rigorous cleaning regimes. Likewise, with an increased focus on workplace safety, vertical ladders, handrails and rescue systems are now an integral part of reservoir design. Reservoir design aspects with a view of longevity and cost effectiveness.

-Close

During February and March Singleton experienced several major rain events. That led us to look at ways to better manage peak wet weather flows (PWWF). We then went about analysing inflows to the plant at certain times and duration. This was then compared to the rainfall received and at what time by recording it on a two hour basis. By using this data and then analysing what the capabilities of the plant of the plant were we developed control measures which were then incorporated into a new PLC program. This program is flexible enough to handle PWWF of a short duration e.g. thunderstorms, along with a PWWF of longer durations e.g. floods.

-Close

Googong Water Treatment Plant (GWTP) was commissioned in 1979 with a capacity of 180ML/d; in 2004 the capacity was increased to 270ML/d with the construction of a parallel Dissolved Air Floatation in Filter (DAFF) plant. In this time however the profile of the dam has changed and the plant now has to cope with water that is outside of the design specifications of the plant. Algal blooms, high colour and higher metals have appeared in the source water. The combination of raw water quality, an increase in coagulant and the introduction of powdered activated carbon and pre-treatment lime have resulted in a large increase in the volume of sludge produced at the plant. The capacity of the plant’s sludge lagoons and drying beds became a limiting factor in how long the plant could operate continuously.

-Close

Glen Innes Severn Council operates a 7000 EP intermittent decanted extended aeration treatment plant serving the town of Glen Innes in northern NSW. The plant was upgraded from a trickling filter arrangement in 2007, however sludge drying equipment was not included in that upgrade due to budget constraints. The new facility produced a greater volume of sludge, and a volute dehydrator was installed in 2013 to cope with the daily sludge production. Sludge at the Glen Innes plant is varies from 2%- 4% solid content.

The volute dehydrator is a low energy, continuous feed process that raises the solid content to between 12% and 20% depending on operator preference. The resulting product is a moist cake consistency able to be transported by tipper truck. The technology is a direct replacement for belt press or centrifuge, and uses a polymer to coagulate the sludge in a flocculation tank. The coagulated sludge is then massaged in a rotor stator arrangement, whereby the stator consists of many plates that allow water but not solid to escape the volute.

-Close

Despite fundamental similarities in the core processes used in the water treatment industry, every water treatment plant has its own unique characteristics. Operating philosophies are developed to optimize performance of coagulation, flocculation, settling/floatation and filtration in any given facility. It is when the typical or average conditions and quality of raw water vary significantly, that the drive to innovate to improve process capacity becomes a ‘must do’ rather than a ‘nice to do’, and where ground can be broken in order to resolve problems and bridge the gap between the theories of plant design and operation, and the reality of making it work today.

Successful resolution of issues arising due to changing environmental conditions, natural disasters or other influences beyond the control or scope of plant designers, constructors and operators requires a structured approach and attention to detail. Accurate jar testing procedures combined with thorough working knowledge of plant capacity are essential, the knowledge and ideas of a wide range of people needs to be combined and one needs to think outside the box to resolve situations that are themselves outside the box of standard operating conditions.

-Close

As the eventual asset owner and operator of the fluoridation dosing plant, with the responsibility for all future costs together with the associated WHS, asset and risk management issues Port Macquarie-Hastings Council wanted to ensure that this new facility would not be developed and delivered as a simple “least capital cost” solution.

-Close

An overview of the purpose, methodology, key findings and recommendations of recently completed national research which explores the future demand for vocational education and training (VET) by employers in the water industry and the capacity of the training system to respond to that demand. The research was driven by the need to ensure that our training system can cope with the anticipated demand for training and skills recognition arising from the introduction of national Certification of Operators within Drinking Water Treatment Systems. Comprehensive data from state and local government water utilities and private sector employers and from Registered Training Organisations (RTOs) currently offering training from the Water Training Package (NWP07).

It finds that there is likely to be sufficient capacity in the training system to meet most of the anticipated training need, however there are inefficiencies within the system that inhibit delivery and which impact on access to and quality of training, in particular.

-Close

In recognition of the importance that the training, experience and competence of water treatment operators has on the production of safe drinking water, in 2010 the Victorian Department of Health, members of the Victorian Water Industry Association (VicWater) and WIOA collaboratively released the “Victorian Framework for Water Treatment Operator Competencies – Best Practice Guidelines”. Reports on the development and implementation of both the Victorian and National Certification processes.

-Close

To address the shortfall in supply and to provide certainty for the future, Orange City Council is constructing a pipeline from the Macquarie River to Orange. The design and development of this project has taken into account the existing and future water needs of the Orange community; justification of this project; projected population growth; secure water yields with demand management measures in place; and potential environmental, economic, community and climate change impacts. The project is being undertaken as part of a broad based water supply strategy for the next 50 years and beyond which focuses on ongoing water conservation, quality and demand management and the provision of key water supply infrastructure at least 10 years in advance of projected demand.

-Close

Stromlo Water Treatment Plant is a 250 ML/day DAFF plant which operates with two disinfection barriers: ultraviolet irradiation and chlorination with chlorine gas. Chlorine contact time is provided by the 34 ML capacity Stromlo Balancing Reservoir, before treated water is supplied to the distribution system. Results of the analysis of 12 months of operating data using the WIOA WTAnalyser Disinfection Tool. The outcomes of the analysis are a clear understanding of the operating range of the disinfection system and chlorine contact times. The impact of final pH and corrosivity management on disinfection effectiveness is assessed.

-Close

Storage reservoirs play a key role in delivering safe drinking water to the consumers. A regular inspection program is essential to determine any hazards or risks to this important product. With a focus to preserve and protect water quality, a thorough external inspection of the tank and surrounds can give operational staff valuable clues towards identifying any contamination issues. This paper is about the stepped inspection process and evidence gathering exercise that will indicate the most commonly found contamination areas of a water tank.

-Close