Executive Summary
The Landholders Driving Change ( LDC ) project is one of two Major Integrated Projects ( MIPs ) funded by the Queensland Government . The LDC was co-designed with landholders to pilot innovative methods to improve water quality ( sediment and particulate nutrients ) entering the Great Barrier Reef ( GBR ) lagoon . This phase of the LDC Project , managed by NQ Dry Tropics , has worked collaboratively with landholders in the Bowen , Broken , Bogie ( BBB ) catchments in the Burdekin region near Collinsville from 2017 to 2021 .
One of the primary objectives of the Landholders Driving Change ( LDC ) Project is to demonstrate the ability of land management and catchment remediation efforts to reduce sediment and associated particulate nutrient loads exported from the Burdekin River to the Great Barrier Reef ( GBR ). This corresponds to the key evaluation question for the project : To what extent has the LDC Project contributed to improved pollutant loads ?
This is further broken down into the following questions for the annual Performance Reports :
• Performance Report Q1 . What are the long-term measured pollutant reductions at a property level in outputs of sediment and particulate nutrients in response to actions initiated under the MIPs ?
• 2021 Performance Report Q2 . What are the predicted ( modelled ) water quality outcomes at the basin / catchment level , and how do these compare to Reef 2050 Water Quality Improvement Plan pollutant load reduction targets ?
• 2021 Performance Report Q3 . What are the modelled pollutant reductions in the MIPs subcatchments as a result of the MIPs investment ?
This is no trivial task due to the size of the broader Burdekin Basin area , the mean sediment load exported from the basin and the BBB catchment , and the inter-annual variability in the sediment / particulate nutrient loads . Accordingly , this question cannot be demonstrated by monitoring sediment loads at the end-ofcatchment alone and requires an integrated monitoring and modelling approach . There are limitations in the level of accuracy that can be achieved through both monitoring and modelling leading to some uncertainty in estimated reductions . These challenges are explored further in the LDC Water Quality Monitoring , Modelling and Reporting Implementation Strategy . The modelled estimates at the catchment scale are generally accepted as the best estimates based on the best available knowledge at this time .
It is also important to acknowledge that improvements in land condition can have a large influence on runoff and associated sediment losses which need to be benchmarked against natural variability in land condition ; in particular , groundcover can change greatly seasonally and year to year . This is driven by management but is also heavily driven by climatic conditions in terms of coverage ( e . g ., high rainfall typically leads to higher cover efforts ) and composition , which are both important for sediment losses and local hydrology . Improvements in land condition are expected to have additional ecological , economic , and social benefits within the local area . Therefore , the success of the program hinges on increased stewardship by local communities and reporting of the local social , economic , and cultural benefits is critical to achieve water quality outcomes . Accordingly , the following additional Key Evaluation Questions ( KEQs ) are also relevant to long-term water quality outcomes :
• To what extent has LDC contributed to an improved culture of stewardship ?
• To what extent have graziers adopted improved land management practices ?
• To what extent have major gullies been remediated ?
While aspects of the first two questions are covered for context only , the results of the major gully remediation projects are reported . Within these questions , project costs and cost-effectiveness are important components of project evaluation and are therefore included in this report .
This document reports the outcome of the water quality components of the Landholders Driving Change ( LDC ) Project in the Bowen Broken Bogie ( BBB ) catchments in 2020-2021 ( Year 4 ), as well as the overall
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