Pumped intake systems that deliver water for irrigation centre pivots require reliable flow volumes and high quality water, to operate efficiently.
Installing Fish Exclusion Screens on pumped intakes protects water control infrastructure, whilst following best practice guidelines for fish protection.
Fish Exclusion Screens maximise operational efficiencies to deliver reliable irrigation flows, whilst reducing maintenance issues associated with pipe and nozzle spray blockages.
An irrigation operator in the South Island of New Zealand recently replaced the intake screen on the property’s pump station that draws water from Lake Benmore. The original screening system had a mesh type screen which used water pressure to keep the screen debris free. This method and type of screen wasn’t effective for the Lake conditions which resulted in inefficient operation and high maintenance. Additionally, the requirement for increased flow prompted the decision to look for an alternative screen solution.
An AWMA self-propelled, self-cleaning cylinder screen was supplied to provide a sustainable pump intake screening solution. Due to factors including; variable lake levels, lake conditions in high winds, rain events and high silt movements in the lake, it was determined that the AWMA Submersible Intake Screen was the ideal solution. This system consists of a 12m long suction line of 500mm diameter pipe with a twin pontoon and self-propelled, self-cleaning screen.
The innovative pontoon system allows for the intake screen to be lowered to sit on the lake bed and then raised to the water surface as required for inspection and/or maintenance. The self-cleaning screen functionality has a unique internal and external brush system, with self-propelled operation for applications where there is no power source available.
The AWMA Submersible Pontoon operates by filling the suction lines and pontoons with water to lower the infrastructure to the lake bed. Replacing the water with air then raises the pontoon to the water surface.
The Lake Benmore Submersible Intake Screen can be lowered to sit on the lake bed at a depth up to 2m, it is designed to operate with low velocities to ensure minimal silt disturbance. It is also compliant with ‘Fish Screening: best practice guidelines’.
It’s working a treat - all is going well and I’m enjoying the time I’m not spending at the pump shed. We are currently running 236 litres / second which is fantastic” – Mike King - Farm Manager.