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Technical Features
SMALL WATER AND WASTEWATER SYSTEMS
into the SCADA computers that are generally located in the power stations of each community. Due to a lack of reliable communications of the local telecommunications networks, it is not possible to view this SCADA network offsite for the majority of these systems. Power and Water is currently working through a project to integrate the SCADA of each community into the Remote Operations SCADA Network. This network is a mix of DET Satelllite network and the Government’s Fibre Network. This is a long-term project that is in its infancy and will enable the automation of data collection, and access to these sites over the network by the Power and Water service co-ordinators. Until such time, viewing of the SCADA is only possible within the community. To overcome the issue of lack of visibility, a web-based telemetry system has been installed in each unit that is able to generate alarms that are sent to the ESO and Power and Water operational staff via email and text messages. This system can also access trends generated from the PLC. This system uses either Next G or Satelite Phone systems. The web-based system generates alarms for 2ppm and 5ppm leaks, Total Chlorination Failure and Total Fluoridation Failure. Upon receiving such an alarm, Power and Water personnel will contact the ESO and talk him through fault finding. In the case of Total Failure alarms, the ESO is directed to attend site and investigate the OIP to determine the cause of the alarm. In the case of chlorine leak alarms, a PWC staff member will take responsibility for remedial action and the ESO will be directed to evacuate site.
process lasted for some six to eight hours and, in some cases, were under difficult conditions imposed by the large tides at the beach landing. With careful planning and safe execution the delivery process did overcome all adversities.
the following organisations which contributed greatly to this project: the Department of Health (Oral Health) for driving the fluoridation project and Oral
With the handover of the functioning systems to operational staff, the challenges in operating such systems continue. The removal of sodium hypochlorite removes some major operational challenges; however, new challenges do arise.
introduction of fluoridation to community
The day-to-day tasks carried out by the ESOs to maintain disinfection are reduced, however the addition of fluoridation adds new knowledge and tasks. ESOs must be trained in the safe handling and operation of chlorine gas and fluoride systems. Power and Water is continuing to work through options to determine the most effective method for delivering of chlorine gas drums to these remote areas.
Water Quality and Treatment team and
The systems are under a six-monthly maintenance contract with West Water NT. However, the ESOs complete regular checks to look for any signs of wear and tear or abnormalities, which are reported to Power and Water for immediate action. The development of the SCADA network and ability to monitor system performance will be a huge development in the operation of these systems. This will remove the sometimes difficult task of fault-finding via telephone discussion and allow more experienced operational staff to monitor alarms and trends over time.
CONCLUSION
Site installation and commissioning was relatively simple due to Factory Acceptance Testing (FAT) off-site. The major difficulties experienced with the installation were to do with the logistics of delivery.
Despite the challenges in implementing a project of this size under difficult logistical conditions, a moderately simple system has been developed that can now be used across a number of remote sites in the Northern Territory.
Meeting design criteria for the buildings to be cyclone-resistant, vandalproof and long-lasting in construction did pose some challenges with transport.
Upon completion of this project, the communities of Maningrida, Wadeye, Wurrumiyanga, Angurugu and Gunbalanya will no longer battle with the issues surrounding sodium hypochlorite disinfection in isolated areas.
WATER JUNE 2013
The Authors wish to acknowledge
ONGOING OPERATIONAL CHALLENGES
INSTALLATION
With the exception of Gunbalanya, all units have been delivered to site by sea. It was necessary to charter a dedicated barge to transport the two buildings on their respective trailers with prime movers, along with a 110-tonne crane, a trailer of counter weights and a frontend loader. The unloading and placement
ACKNOWLEDGEMENTS
The introduction of fluoridation to five remote communities is a huge leap forward in the provision of oral health services to the communities of Maningrida, Wadeye, Wurrumiyanga, Angurugu and Umbakumba.
Health Promotions for promoting the members; the Anindilyakwa Land Council and Groote Eylandt Bickerton Island Enterprises for funding the Groote Eylandt fluoridation plants; PWC’s Remote Operations unit, particularly the Water and Sewerage Operations teams, the Infrastructure Delivery Teams.
THE AUTHORS Dr Bridget McDowall (email: bridget.mcdowall@ osmoflo.com.au) is is a Chemical Engineer with nine years of experience in the Australian water industry. Bridget managed this project while working as a Senior Water Treatment Engineer in Power and Water Corporation’s Remote Operations unit, based in Darwin. Reg Wagland (email: rwagland@ww.net.au) is the General Manager of WestWater Enterprises. He has expertise developed over 54 years in the water industry commencing with his electrical apprenticeship at the Sydney Water Board. He also has extensive knowledge in the area of industrial instrumentation and automatic process control gleaned from many years of experience in the iron ore and alumina industries. Amy Dysart (email: amy.dysart@ powerwater.com.au) has been with Power and Water Corporation for over eight years and has been responsible for managing and planning for water and wastewater in service in the remote communities of the NT for most of that time.
REFERENCES www.workingfuture.nt.gov.au/growth_towns.html Victorian Code of Practice for Fluoridation of Drinking Water Supplies, www.health.vic.gov. au/environment/fluoridation/code.htm