COWRA SHIRE TOWN WATER SUPPLY SYSTEM
3 3 Refurbishment of River Low Lift Pump System and associated infrastructure

Cowra Shire Council required a Design and Construct upgrade of the existing Lachlan River Low lift pump station which houses three pumps in a Wet Well connected to an internal manifold that directs water via a pipe out of the well up to a higher lift pump station holding tank ,the existing pumps are well past there life span with one pump not functioning at all and the second pump constantly breaking down this leaves the town very vulnerable to supply failure, as part of the upgrade council has requested that the river inlet pump station below the Low Lift Wet Well be upgraded at the same time as a permeant back up to the existing Low lift pump station as part of this project this would give council a fully functioning system while the major upgrade to the Low Lift Pump Station was carried out and would eventually supply council with 2 individual supply systems from the Lachlan river. This project aims to secure the water supply delivered from the low lift pump station to the high lift pump station and allow the flow rate to be scaled down and up with variable speed drive pumps with flow fluctuation from 30l/s up to 280l/s and to create redundancy with at least one extra pump from the low lift pump station to the high lift pump station as well as the two river lift pumps as back up.

Works Undertaken

Low Lift Pump System

• Supply and install 3 Capari Cast Electric Submersible Low Lift Pumps 52kw on heavy-duty Stainless-Steel pump column complete with all required stainless-steel fittings.
• All required Guard rails, S/S Safety chains and Duck feet pedestal on each pump for automatic coupling and uncoupling of pumps.
• Stainless Steel Hydraulic Manifold arrangement at well head including NMI Certified 400mm Water meter with remote display to interface with councils clear Scada control system and to monitor water depth and current and cumulative flow rates to council reservoir.
• Gate Valves, Check Valves, and all associated connection fittings to link all the 3 pumps to the existing holding tank via 3 independent 315mm poly discharge lines.
• Design supply and install suitably sized consumer mains from the pumps to the electrical control room.
• Design supply and install Variable Speed Pump Starter.
• Supply and install 600mm Stainless Intake Manifold for backflushing River intake Screens
• Testing and Commissioning

River Lift Pump System

• Install 2 Grindex Cast Electric Submersible Low Lift Pumps 37kw on heavy-duty Stainless-Steel pump column complete with all required stainless-steel fittings.
• All required Guard rails, S/S Safety chains
• Stainless Steel Manifold arrangement at well head including NMI Certified 300mm Water meter with remote display to interface with councils clear Scada control system and to monitor water depth and current and cumulative flow rates to council reservoir.
• Gate Valves, Check Valves, and all associated connection fittings to link all the 2 pumps to the existing holding tank via a independent 315mm poly discharge line.
• Testing and Commissioning

Highlights, Innovations and Key Risks

• Infield modifications to adapt to council requirements.
• No major disruption to town water supply through the project duration.
• Ongoing discussions with council to improve the water supply system
• Excavation and pipe laying in proximity to existing infrastructure.
• No underground service strikes for the duration of the project