Seqwater is undertaking an $11 million waterworks package to deliver up to 50 per cent more drinking water and boost water security for the suburbs north of Brisbane and the Sunshine Coast. The package is being delivered through a range of projects including the installation of new valves and upgrades to a number of pump stations to help increase transfer capacity of the area’s bulk water supply transport network. Here, we look at the works completed and being undertaken.
The SEQ Water Grid is made up of a connected network of dams, water treatment plants, reservoirs, pump stations and pipelines that allows treated drinking water to be delivered around South East Queensland as needed.
Investment in water supply assets such as pipelines, pump stations and treatment plants are vital to better managing peaks in demand during hot, dry weather, with the series of projects being undertaken by Seqwater through this package of works aiming to increase capacity in the northern section of the SEQ Water Grid.
As part of this waterworks package, Seqwater is upgrading the northern transfer capacity of the bulk water supply transport network between Sparkes Hill Reservoir and Aspley Reservoir. The project aims to better enable water from the Mt Crosby Water Treatment Plants (WTP) to be transferred north to supplement the supply at the North Pine Water Treatment Plant, which in turn can service the northern region of the SEQ Water Grid.
To do this, the transfer capacity from the Mt Crosby plants will be increased to about 125 megalitres per day to supply areas normally serviced by North Pine WTP.
Seqwater Chief Operating Officer, Stuart Cassie, said, “In the event of low storage levels at either North Pine Dam and/or Baroon Pocket Dam, production would need to be significantly reduced at their respective plants; the North Pine and Landers Shute Water Treatment Plants.
If this occurs, a greater capacity is required to supplement supply to either the Moreton Bay and Sunshine Coast regions. This project helps meet that need.
“Investing in this section of the SEQ Water Grid will particularly benefit Moreton Bay and Sunshine Coast, allowing more drinking water to be transported in times of peak demand and help to reduce pressure on our Sunshine Coast dams.”
Mr Cassie said the adopted solution to achieve this increase is to utilise the Lloyd Street Pump Station to pump directly to Aspley Reservoir by bypassing the Sparkes Hill Reservoir. “This involves converting the Lloyd Street Pump Station to variable speed operation, modifying pipework at Sparkes Hill to include a series of control valves that open the reservoir bypass pipework and close the reservoir outlet and restrict inlet flow.
“In addition, pressure reduction valves (PRV) are to be located on Urban Utilities-owned Pickering Street and Kitchener Road offtakes to restrict the pressures entering the reticulation network when the bypass pumping is in operation.
A replacement of the existing air valve on the Seqwater main at Appleby Road is also required to accommodate the transients pressures in the new mode of operation,” Mr Cassie said. Seqwater is working with contractors Heaton Plant and Pipeline for the civil package of works (valving and mechanical works) at Sparks Hill, and CV Services Group for all the pump station upgrades at Lloyd Street and Byrnes Road, as well as Sparks Hill electrical integration with collaboration with Heaton.
Projects being undertaken as part of the package
Some of the projects and works being undertaken by Seqwater as part of the $11 million package include:
Major bypass pipework at Sparkes Hill Reservoir
The installation of a major bypass pipework at Sparkes Hill Reservoir #2 will increase the maximum northern flow transfer capacity into Aspley Reservoir to 125ML/d. This is to be achieved by utilising the existing Lloyd Street Pump Station to pump past Sparkes Hill Reservoir (bypass) into Aspley Reservoir.
Valving is to be added to pipework at Sparkes Hill Reservoir to facilitate this functionality and the pumps at the Lloyd Street Pump Station are to be converted to variable speed operation. Pressure reducing valves (PRVs) are also required to be added to offtakes from the main to the Urban Utilities network to manage pressure increases in the transfer main, which would otherwise enter the reticulation system.
Improvements to the Sparkes Hill Northern Inlet/Outlet
• Construction of a valve pit for the DN500 actuated butterfly valve including the supply and installation of valving and associated pipework and connections to the existing mains
• Supply and installation of a DN600 actuated butterfly valve and associated pipework modifications for installation within an existing valve pit on the outlet of Sparkes Hill Reservoir #1
• The construction, including supply of all materials, for a new DN600 pipeline connection from the QUU DN600 main to the existing DN1200 Sparkes Hill Reservoir #2 connection main:
- The supply and installation of an electric actuator onto the existing DN1200 butterfly valve
- The construction of a new DN600 pipeline from the existing DN600 gate valve, including the supply and installation of bypass valving, air valve, and pit and connections to the existing QUU DN600 main
• The supply and installation of a gearbox pit over the existing DN600 gate valve
• The construction of a valve pit for the DN750 actuated butterfly valve including the supply and installation of valving and associated pipework connections to the existing main
• The removal of existing pipework and relocation of existing services as required to complete new installation works
Sparkes Hill Southern Inlet/Outlet
- The refurbishment of an existing DN750 valve pit including supply and retrofitment with a DN750 actuated plug valve
- The construction of a flowmeter chamber for a new DN750 insertion flow meter, including supply and installation of the flowmeter
- Supply and installation of a scour valve onto existing DN750 main
Upgraded pumps at Lloyd Street Pump Station in Enoggera
In order to increase the maximum northern flow transfer capacity into Aspley Reservoir to 125ML/d, the pumps at the Lloyd Street Pump Station will be utilised. Valving is to be added to pipework at Sparkes Hill Reservoir to facilitate this functionality and the Lloyd Street pumps will be converted to variable speed operation. Work includes:
- Detailed design of pump station upgrade
- Replacement of motors on existing pumps 1, 2 and 3
- Replacement of pump motor soft starters with VSDs
- Provision of air conditioning system to pump hall
Upgraded infrastructure at Kitchener Road, Stafford Heights
PRVs are required to be added to offtakes from the main to the Urban Utilities network to manage pressure increases in the transfer main which would otherwise enter the reticulation system.
Along with the installation of a flowmeter, these upgrades will increase Seqwater’s ability to distribute water north from the Mount Crosby WTP. The PRV sites are built to SEQ Code – a consolidated set of design and construction standards for retail water supply and sewerage infrastructure in South East Queensland – and Urban Utilities standards as these will become their assets.
Completing the Stafford Heights upgrade
The PRV and flowmeter that were required for the upgraded infrastructure at Stafford Heights were installed between the Seqwater network and the Urban Utilities’ DN750 trunk main at Kitchener Road.
The project was funded by Seqwater, and engineering company KBR was engaged to undertake detailed design of the asset which would ultimately be handed over to Urban Utilities.
A critical part of this package of work was successfully completed over the weekend of the 26-27 September 2020, after a long period of collaboration between Seqwater, Urban Utilities, KBR and Dormway. Installation of the PRV required a significant shut down, and as Kitchener Road is a busy urban road and the installation site was immediately in front of a school (within the pick-up and drop-off zone), careful planning was undertaken to ensure these works were done in school holidays, over the weekend and at night to ensure that minimal disruption to the public was experienced.
Urban Utilities was required to operate over 30 valves to isolate this critical trunk main, and Seqwater was required to operate a 750mm gate valve located on the corner of Kitchener and Appleby Roads. Over 800 homes were letterbox dropped by Seqwater to inform customers of the potential water supply impacts. The school and local businesses in the close vicinity to the job site were also involved and kept informed.
Upgrading the Byrnes Road Pump Station Seqwater is also completing upgrades to the Byrnes Road Pump Station as part of the investment in water security boosting infrastructure to increase the flow capacity from the pump station to Narangba Reservoir to 43ML/d. Mr Cassie said the increased flow capacity will be achieved by using the pump station’s existing two pumps to move water to the Narangba Reservoir and converting them to variable speed operation, with a third pump to be installed to provide standby capacity.
“The project also allows for the parallel operation of North Pine Pump Station in conjunction with Byrnes Road Pump Station to maximise the ability to transfer water north into the Northern Pipeline Interconnector (NPI) whilst allowing areas to the south to be supplied from the Mt Crosby WTP,” Mr Cassie said.
The Byrnes Road Pump Station Upgrade includes:
- Detailed design, supply and installation of pump 3 and associated pipework
- Replacement of the main switchboard
- Upgrade of power supply to main switchboard
- Replacement of motors for pumps 1 and 2
- Provision of VSDs for pumps 1, 2 and 3
“The Byrnes Road Pump Station has been completed from a mechanical and electrical prospective, however the automation and network-wide SCADA integration is currently underway,” Mr Cassie said.
Complimentary works to improve water quality
To compliment the works being undertaken as part of the $11 million waterworks package, an additional $9 million was invested to build the new Aspley Water Quality Facility (AWQF).
Mr Cassie said the AWQF improves the quality of water that is being distributed from the Aspley Reservoir and allows more treated drinking water from Brisbane’s main treatment plants at Mt Crosby to move safely into the northern parts of the SEQ Water Grid.
“A dosing station has been constructed at the reservoir inlets and outlets, with the ability to dose water being transferred in a northern direction. It cannot operate in a southern flow direction based on the current control system configuration. “It includes a new inlet control valve and connection from the Sparkes Hill to Aspley main for northerly flow operation.”