Wallsend 2 SFPS & Rising Main Upgrade
About the project
As part of Hunter Water’s program to improve the reliability of its systems through the upgrade of ageing infrastructure assets, Pensar was successfully awarded the design and construction of the Wallsend 2 Storm Flow Pump Station (SFPS) and Rising Main project. The upgrade included the replacement of 1.4km of DN600 rising main, refurbishment of the existing pumping station including electrical infrastructure, and construction of an odour control facility.
This upgrade was required due to the ageing infrastructure installed from the pump station, along the 1.4km pipeline to a connection point at the Shortland WWTW. The pipeline route is located within Hexham Swamp Coastal Wetlands, under Dark Creek and adjacent to an abandon tipping site.
Location
Wallsend, New South Wales
Client & Duration
Hunter Water
Jul 2023 - Mar 2025
Project Scope
Pump Station:
- Wet well pump replacement (three variable speed pumps operating in duty/assist/ standby capable of transferring flows to Shortland WWTW between 460 L/s and 800 L/s
- Valve pit refurbishment/augmentation (thrust type dismantling joints, isolation valve and non-return valve connecting from each pump and access)
- Lining of the existing pump station structure
- Construction of new odour control system with capacity of 617 L/s
- Construction of new electrical kiosk and switch room.
Rising Main:
- Upstream connection (buried connection between the pumping station, the Phase 1 works (replacement of existing tee and the new rising main)
- Lining of the existing pump station structure
- Downstream connection (provide a buried connection between the new rising main to the existing DN750 DICL pipework)
- 3 x horizontal directional drilling sections (Section 1 - 460m, Section 2 - 248m, Section 3 - 390m)
- Construction of new hardstand and access tracks as required for construction, operation, and maintenance works.
Challenges
- Small mainline easement between coastal wetland and neighbouring properties which was precisely traced during HDD operation
- A detailed shut down and cut over plan is developed, including details of temporary arrangements necessary for the construction of works
- Complicated and unknown services within the Shortland WWTW inlet works. Pensar pivoted to adjust to unforeseen conditions
- The project had several environmental constraints including a coastal wetland, creek crossing, buried hazardous materials and acid sulphate soil. Careful planning and consideration to ensure minimal disruption to the environment and construction program.
Achievements
- Pensar’s detailed design for the upgrades at the Wallsend 2 SPFS site, the upstream and downstream rising main connection points, the trenchless and trenched rising main including, but not limited to, process, hydraulic, civil, structural, mechanical, electrical & controls, telemetry, consultation, survey, geotechnical ensured Hunter Water's specified design and performance requirements were achieved
- Successfully completed a largescale isolation for the Shortland WWTW inlet connection work which involved isolation of 10 pump stations over one night shift
- Pensar supported local business engagement and the inclusion of First Nations People within the workplace and actively sought to provide opportunities for employment and training for members of these communities through our Aboriginal Participation Plan tailored for the project.