Final LDC WQ Report | Page 44

reductions , however , the differences between the other sub-catchments were less significant in the modelled output .

For PP and PN , the relative contribution from the Bowen sub-catchment was considerably higher than all other sub-catchments . Further discussion of these results in the context of potential future priorities is discussed in conjunction with project types and project areas in Section 7 .

Table 9 . Predicted fine sediment savings at the sub-catchment scale because of projects initiated by the LDC Project across all years of reportable practice change 2019 – 2021 . Represents report card years 2019-2021 ( RC # 10-12 )

Bogie 2.2 0.0 0.0 < 1 % 0 % 0 %

Bowen 4,935 5.4 6.6 68 % 81 % 68 % Broken 136 0.4 1.0 2 % 6 % 10 % Glenmore Creek 1,893 0.8 1.8 26 % 12 % 19 % Little Bowen 11 0.0 0.0 < 1 % 0 % 0 % Pelican Creek 2,45 0.1 0.2 3 % 1 % 2 % Rosella Creek 9 0.0 0.1 < 1 % 0 % 1 % Total 7,230 6.7 9.7

Additional detail to support the modelled results

Additional detail provided in relation to Performance Report Q1 is also relevant to Performance Report Q2 and Q3 . Further information on the development of the fine scale model is provided below .

Supporting monitoring information

Rainfall and river flow Rainfall and river discharge are important drivers of catchment water quality and essential context for variations in annual water quality characteristics .

The Burdekin River catchment had an average-sized water year ( October 2020 to September 2021 ), with approximately 8 million megalitres ( ML ) measured at the Clare flow gauge to date . Most of the discharge was sourced from the catchment area above the Burdekin Falls Dam .

P2R sub catchment monitoring sites at Myuna and Strathalbyn As described in the LDC WQ MMR Implementation Strategy , the Great Barrier Reef Catchment Loads Monitoring Program has a site in the BBB catchment , Bowen River at Myuna ( gauge 120205A ) ( Lat - 20.58333 , Long 147.60000 ). This captures 7,104 km ² , or 75 %, of the catchment . At this site water quality and discharge data is collected monthly and during high flow events . A second site was set up at Bonnie Doon Creek at Strathalbyn Station ( Bonnie Doon Creek at Strathalbyn – 1200125 ) in July 2018 as part of the Greening Australia gully remediation project . The aim of this new site is to collect data that will contribute to a further understanding of soil and nutrient processes , which in turn , will help validate the modelling of the BBB catchment . It will also help to evaluate how gully restoration in this area is contributing to sediment reductions entering the sub catchment waterways .

The data for Myuna was reported in the LDC WQ MMR Implementation Strategy from 2012-13 to 2016-17 . Updated data for both locations is available from DES . The Bonnie Doon Creek data is available from December 2018 , and the Myuna data is available from April 2014 . This information was incorporated into the Source Catchments model and is not presented here . However , it should be noted that given the variability in rainfall between years , the catchment monitoring data is most useful as a validation tool for the

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