For wet season runoff capture , there was previously no effective capture modelled for the wet season ( late Dec-mid March ). Rules currently under consideration ( as at October 2018 ) are :
� If runoff > 5-10mm then the pit is considered to be full . � If follow up rain occurs then the runoff component is lost due to pits being full , also no irrigation occurs � If no follow up rain occurs , then irrigation is scheduled and the pit is emptied again .
Pesticides The pesticide modelling scenarios are still being revised ( as at October 2018 ).
5.2 Deriving pollutant load estimates for the 2016 Report Card ( released in 2017 )
The description in Attachment 2 provides a summary of the methods for the Burdekin DIN runoff model for the 2016 Report Card , compared to the 2015 Report Card ( presented in the Burdekin WQIP 2016 and used for the management scenarios ). These are provided for reference only and it is important to note that these are currently being updated with additional data and expert input for the next Report Card to be released in 2019 .
The 2016 Report Card results indicate that improvements in irrigation management would provide the best outcome in terms of reducing DIN losses to the GBR . This result is different from Report Cards 2014 and 2015 where the benefits from improved fertiliser management were similar to improved irrigation management . A major factor driving this result ( particularly for the BRIA area ) is the quantity of DIN lost from irrigation runoff . In the 2016 Report Card , irrigation runoff was modelled as a static concentration throughout the year with a concentration of 0.6 mg / l . This DIN concentration is approximately 5 times the default minimum DIN runoff concentration 0.11 mg / l ( which is close to rainfall concentrations ) for other sugarcane growing regions . The setting of the irrigation runoff concentration can have a large impact on the modelled DIN losses in the Burdekin and hence , is currently being updated for the next Report Card to be released in 2019 . Discussions with the modelling team indicate that the changes are not expected to be significant .
6 Current adoption of management practices for improving water quality from Lower Burdekin sugarcane
6.1 Current adoption of sugarcane management practices
Management practice adoption data is available and interpreted through the Paddock to Reef program which draws on several sources in the region . The Paddock to Reef program has recently undertaken a major exercise to update the benchmarks for reporting current adoption . The benchmarking data is informed by information from 2015-16 , 2016-17 and some 2017-18 data , and will be reported in 2019 as the reporting benchmark for the for 2016-17 year . The primary data sources for benchmarking management practices in Lower Burdekin sugarcane and their coverage is shown in Table 6.1 .
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