• 6 % of all gullies contributed 30 % of the total fine sediment yield .
• Gully clusters ( i . e ., groups of gullies with their outer margins < 10m apart ) contributed ~ 390 kt / yr of fine sediment from just 200 ( or 2 %) of all clusters .
Targeting these high yielding gullies or gully clusters provides the means to achieve the greatest water quality improvements in the shortest possible time . The five sites that were identified for detailed site scale analysis through the preliminary prioritisation ( section 5.1.1 ) at the project outset are all within the top 73 clusters .
Section 6 presents some of the additional outcomes of the LDC Project relevant to this report . It highlights that :
• Water quality monitoring and evaluation must be targeted , consistent , preferably long-term and clearly communicated ;
• Collaborative technical input and recognition is essential ;
• Significant increases in the adoption of practice change in the BBB have been documented ;
• A better understanding of KASA ( Knowledge , Aspirations , Skills and Attitudes ), barriers and enablers to change provides valuable insights for future program design ; and
• Costs and cost-effectiveness and associated landholder perceptions are a critical aspect of prioritisation and design of gully projects .
Section 7 draws all of this information together to make recommendations for prioritisation and design of investment in reducing fine sediment and particulate nutrient loads from the BBB to the GBR . It presents sub-catchment load contributions to identify spatial ‘ hot spots ’ for fine sediment delivery in the BBB , provides guidance for prioritising landscape remediation activities , makes recommendations for future investment and design and identifies needs for ongoing water quality monitoring and evaluation . Table I summarises some of the key characteristics for each sub catchment .
Overall , the monitoring and evaluation of water quality measures in the LDC Project has provided a strong foundation for estimating the outcomes of the investment and has delivered valuable guidance for ongoing implementation of similar projects in the BBB . The combined monitoring and modelling approach will continue to provide the benefit of being able to estimate water quality outcomes across large scales , while providing confidence in the outcomes through additional validation with monitoring data .
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