Dubbo Regional Council in New South Wales’ Orana Region has been undertaking a range of upgrades, and water and wastewater projects across its jurisdiction to meet the demands of the community, replace aging equipment, increase water security and improve the efficiency of the site. Here, we look at some of the projects being undertaken by the council, the procurement process for the pumps, and the design and construction process.
Upgrading the Mumbil Raw Water Pump Station
An upgrade to the raw water pump station in Mumbil, a small town between Wellington and Orange in Dubbo Regional Council’s jurisdiction, has required careful consideration of pumping equipment to ensure it was able to meet the changing demands of the site, while also being compatible with the existing site.
Julian Geddes, Director Infrastructure at Dubbo Regional Council, said when selecting a pump for an existing location like Mumbil, it was important to consider the existing infrastructure.
“Needs change over time and what was once a suitable solution may not be the case now. The existing pumps in Mumbil were no longer available, and another type/model was needed,” Mr Geddes said.
“The current flow rate is 7L/s into a 151m/h. The current pipework or rising main on this installation are aging pipes, so one of the considerations was not to increase the head pressure as this may lead to pipe failures.
“The water at this site is not very aggressive so corrosion is not an issue; however, in some cases like irrigation the well water can be very aggressive and can destroy a pump that is not suitable.”
Selecting pumps for projects and maintaining them
Mr Geddes said along with factors like those presented in the Mumbil Raw Water Pump Station upgrade, there are a number of other factors that are considered when selecting a pump for a project including head pressure, required flow, motor starting method, condition of water being pumped, reliability and serviceability of pumps.
As always, cost is an important consideration for all aspects of maintenance and repairs. In some cases, the right pump may have a higher installation cost, but it may be the best solution for the long term by reducing downtime from repairs and failures,” Mr Geddes said.
In order to identify issues early and reduce downtime, and to maintain efficiency levels, pumps across all Dubbo Council assets undergo a range of testing where possible, including:
- Insulation testing of the motor winding to identify issues or cable breaking down
- Flow charting – a drop in the flow can indicate pump wear and performance issues
- Onsite visual and audible testing – an audible (listening test) can pick up excess noise and may be a result of a pending mechanical failure
- Current draw – changes in the motor current can indicate issues like wear and poor pump performance
“With bore pumps, there is not a lot of preventive maintenance you can do except to monitor the pump’s output, current, flows, etc.
A visual and audible inspection is a key factor to picking up potential issues, and needs to be done monthly. Having good electronic monitoring systems in place is key to preventing downtime,” Mr Geddes said.
Stuart Town bore brings water security
Located within Dubbo Regional Council’s jurisdiction, Stuart Town has been experiencing water security concerns, exacerbated by the drought.
To address these concerns and build community resilience, Council installed a new bore and non-potable water infrastructure for a water filling station, providing residents access to up to 60,000L a day.
Previously, Stuart Town residents relied entirely on rain water collected in tanks and water carting to supply their needs.
Installing the bore
Council drilled the bore 2km west of the town and installed a connecting pipeline that fills two 20,000L storage tanks at the new filling station adjacent to the local fire brigade shed on the corner of Burrendong Way and Copeland Street.
Chris Godfrey, Senior Design Engineer at Dubbo Regional Council, said the Federal Government provided $560,000 for the works, including completed bore equipment with a submersible pump, automatic backwash filter, electronic controls and a shed.
“The pipeline and reticulation systems for the project were designed by Dubbo Regional Council’s Design Section. The pipeline is constructed entirely from HDPE material and utilises DICL fittings in some locations.
Electrofusion fittings are also utilised. The pipeline diameter varies between DN75 and DN125, and has been designed to comply with the Water Services Association of Australia (WSAA) code for potable water supplies.
The pipeline has also been designed so that it can be expanded in the future, ensuring that it continues to serve the needs of the growing village of Stuart Town,” Mr Godfrey said.
“The submersible pump used for the Stuart Town bore is a Grundfos SP 7-27. It is powered by a single phase 3.7kW motor and is capable of delivering a flow rate of approximately 2L/s at a design head of 120m.
The depth of the bore is approximately 84m, with the pump suction level set at 60m below the top of the well.
“A 130 micron, two inch ‘SpinKlin’ automatic self-cleaning disc filter, manufactured by Arkal, is also installed to prevent the ingress of sand and clay particles into the Stuart Town water supply.
The filter continuously monitors the pressure of its inlet and outlet, and automatically backwashes when the differential between the two reaches a certain threshold.”
Procuring the equipment
Mr Godfrey said Council put out a tender for the construction of the pipeline component of the project with four quotations received, and the contract being awarded to local contractor PTS Group.
“Other major local contractors involved with the project included Watermin Drillers, who drilled and cased the bore; Notts Rural and Domestic, who supplied pipe materials and fittings; Aquawest, who supplied the bore pump, shed and control gear; Imrie, Astley and Associates, who provided survey information and control for the job; Macquarie Geotech, who provided geotechnical investigation for the project; Activenergy, who extended existing powerlines and supplied a new transformer and power connection to the new bore pump; and Nolan’s Earthmoving, who provided bitumen sealing services for the new water filling station hardstand area.”
Providing the community with water
Mr Godfrey said while the water is not drinkable, the new supply can be used for other things such as toilets, showering and cleaning – saving the precious resource for human consumption.
Connections are also going to be made in the near future by Dubbo Regional Council staff to the local primary school and Moxon Park, supplying these facilities with a reliable water supply.
In addition to the water filling station, spring valve fire hydrants have been installed on water mains supplied by the bore in some areas within the village, improving the level of fire protection within those areas.
Commissioning and installing a pump transfer station
The Council has commissioned and installed a new pump transfer station at the Dubbo Sewage Treatment Plant that will see the rapid fill and turnaround of water carting trucks used for dust suppression at roadworks and land development sites around the region to help reduce the burden on town water supply.
There are a number of significant works currently underway around the region that require water for dust suppression. Limiting or removing the need to use potable (drinking) water and replacing it with treated effluent was high on Council’s agenda.
Steve Colliver, Project Coordinator – Drought Coordinated Response Team, said the project was in response to a call from the Federal Government for big water users such as councils to look at innovative and smarter ways of conserving water.
Equipment to meet specifications
Mr Colliver said two key considerations during the procurement process for the equipment was that the pump had sufficient capacity to ensure a quick fill time and could be controlled remotely due to the location of the fill point in relation to the pump.
“Council purchased a Godwin NC100 100mm pump. This is capable of delivering 230m3/h or 1,013 GPM. The pump was purchased in accordance with Council’s procurement policy and the needs determined through the detailed design process,” Mr Colliver said.
A safe alternative
Mr Colliver said using treated effluent is a safe and efficient practice that has been in place for some time, and is ideal for operational use such as dust suppression and irrigation with the latter being the biggest user of Dubbo’s treated effluent.
“While treated effluent hasn’t yet made its way into the community’s everyday psyche or mainstream usage, there is absolutely no reason why a safe and plentiful water source like this shouldn’t be used to reduce the effects of dust during construction rather than use our precious drinking water supplies,” Mr Colliver said.
CEO Dubbo Regional Council, Michael McMahon, said that when people hear the phrase ‘treated effluent’ it instantly conjures up images and misconceptions in people’s minds.
“The reality is, the treated (effluent) water that Council is repurposing is actually very good and is regularly tested to ensure it is fit for purpose for alternative uses, such as these,” Mr McMahon said.
“In 2019, considering all the environmental requirements, regulations, technology and best-in-the-world practices that places like Australia employ to create treated effluent for discharge back in the system, the stigma of ‘effluent’ should be somewhat obsolete.
“Given the need and demand for water in construction, farming and industry etc, having treated effluent at-hand in times of extreme drought is a far, far better proposition than expending precious water supplies on such activities as dust suppression.”
Improving biosecurity with a new truck wash
New water and pumping infrastructure is also being installed as part of a project to install a new truck wash at the Dubbo Regional Livestock Markets, and to increase the site’s efficiency by decreasing waiting times and allowing more efficient movement of vehicles through the wash.
Dubbo Regional Livestock Markets (DRLM) is one of the largest sale yards in the country, with more than 1.3 million sheep, 200,000 cattle, and 9,000 goats being sold annually.
Ross McCarthy, Manager Dubbo Regional Livestock Market, said that with so many animals coming from all corners of NSW and sometimes Queensland, it’s important that biosecurity standards are at their best.
“Decontaminating trucks that transport livestock is an integral part of the agricultural industry’s biosecurity measures, as it is paramount in preventing disease transmission.
The Australian Bureau of Agricultural and Resources Economics and Sciences (ABARES) found that a large-scale, widespread Foot and Mouth Disease (FMD) outbreak would cripple the industry by $50 billion over ten years.
The transmission and impact of a disease like FMD can be reduced significantly with decontamination procedures such as truck washing.”
Designing the truck wash
In addition to the extra wash bay, the following features will be included in the upgrade process:
- New pumps allowing a better and more constant supply of water pressure, allowing fast wash out
- More slope to allow trucks to drain quicker allowing more complete and faster wash out of trucks
- Longer facility so operators are not working in the drainage area of truck wash
- More efficient and effective lighting
- Screens between wash bays
- New screen to reduce waste for better environmental outcomes
- Cameras will be an added deterrent to unsafe behaviour and increase personal safety
Mr McCarthy said Council put out a project tender for public submission, with six businesses submitting a tender.
The successful contract was awarded to David Payne Constructions, a locally-owned and operated business in the Central West.
“The type of pumps used in this project are currently being finalised. New pumps will include one for high pressure washouts and a sump pump similar to Flygt Concertor Pump, Model NX6020.180 7.3kW, duty 40L/sec at 14m head.
In addition to this, the onsite tank is 20,000L at a depth of 3.3m. There’s also stirrer/agitator included as part of the works,” Mr McCarthy said.
Constructing the truck wash
The first sod was turned on 12 February 2020, with State Member, Dugald Saunders, joining Dubbo Regional Council Mayor, Ben Shields, and DRLM Manager, Ross McCarthy. Construction is expected to be completed by the end of April 2020.
The project received $819,467 in funding from Restart NSW under round three of the NSW Government’s Fixing Country Roads Program, with total project cost projected at $1.5 million.