Review of recycle pit applications 2012-2017 - Burdekin Bowen Integrated Floodplain Management Advisory Committee ( BIFFMAC )
BIFFMAC recently completed a review of recycle pit assessments required for funding applications submitted to North Queensland Dry Tropics for construction of recycle pits ( received between March 2012 to October 2017 ) ( Rickert and Kenniff , 2018 ). This review captured details of 54 recycle pits in terms of volume , catchment area , daily inflow rates and use of recycled water ( note that these applications were not necessarily funded ). From these assessments , it was identified that ( extracted directly from Rickert and Kenniff , 2018 ):
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Additional information needs to be collected on how the recycle pit will be utilised / managed to maximise its ’ efficiency and benefit in reducing loss of tailwater to downstream environments . For example information should be collected at the application stage on the likely / proposed usage of the recycle pit such as how often it will be cycled ( filled and emptied ), how the irrigation schedule on the farm will be altered to make use of the recycled water , what volume will be removed from the pit for each irrigation , and evidence of how the water will be distributed across the farm ( map showing pipe and pump infrastructure layout and approximate volumes of water to be applied to ( and collected from ) each block ). This information would enable the assessment to include an analysis of the appropriateness of the size of the recycle pit in relation to the proposed catchment area , recycled water use area and irrigation schedule .
Funding criteria should be improved by ensuring that all applications for recycle pits and associated infrastructure are accompanied by an accurate water balance calculation ( based on actual measurements of the volume of water applied per irrigation and the volume of runoff per irrigation ). Ideally this should be conducted by a suitably qualified expert and delivered as part of a comprehensive irrigation management plan developed for the farm .
The distribution of guidelines for appropriate recycle pit design and management should be provided to all recycle pit funding applicants . Whilst there is no data available to confirm how appropriately or otherwise recycle pits are being managed / utilised across the Burdekin , anecdotal evidence suggests that whilst in many cases the installation of a recycle pit leads to farmers to being more aware of their irrigation management , and managing their irrigation more effectively , there do exist occasions where the installation of a recycle pit has resulted in farmers taking less care with irrigation practices ( e . g . not monitoring the irrigations as closely and allowing water to runoff for a longer period of time ) due of a belief that the recycle pit negates the necessity to manage irrigations as carefully as all runoff water is being captured . However , if the recycle pit is already full from a previous irrigation or is of insufficient volume to collect excess runoff , then an irrigation left on for too long could result in tailwater losses to the environment from the recycle pit overflowing .
� Post installation data should be collected on the use of the recycle pit to establish whether it is being used as proposed and to inform modeling of the effectiveness of recycle pits in reducing runoff to downstream environments . Data such as the total volume of water captured and the volume of water re-used on the farm over a 12 month period would be a minimum requirement . This could be done by installing meters on recycle pit pumps and monitoring the fluctuations in water volume in the pit using pressure transducers with telemetry . This would also yield data on how often the recycle pit overflowed , and when combined with rainfall data , how effective the pit was in collecting first flush events .
7.3.2 Program evaluation conducted through research projects 2008 Lower Burdekin Water Quality Tender
In 2007-08 , a $ 600,000 water quality pilot tender was trialled in the Lower Burdekin River area , funded by the Australian Government through the National Market Based Instruments and co-funded and administered by the NQ Dry Tropics . The Tender had been the first NRM program in the GBR catchment to allocate funding for on-farm projects delivering water quality improvements through a competitive tender process . It attracted 87 bids from 64 landholders for a range of water quality improvement proposals , mostly
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