This product presents the impact and risk analysis for the Gloucester subregion and is a key output of this BA. The structure is as follows:
- Section 3.1 describes the scope of the BA conducted for the Gloucester subregion and summarises the critical philosophical and operational choices.
- Section 3.2 describes the methods for assessing impacts and risks in the Gloucester subregion. It includes details of the databases, tools and geoprocessing that support the impact and risk analysis, and the approach to aggregating potential impacts to landscape classes and assets. The approach is consistent with that outlined in the companion submethodology M10 (as listed in Table 1) for analysing impacts and risks (Henderson et al., 2018), and is in addition to the methods for receptor impact modelling reported in companion product 2.7 for the Gloucester subregion (Hosack et al., 2018).
- Section 3.3 provides a closer look at the spatial extent of hydrological changes within the zone of potential hydrological change, using groundwater drawdown and a subset of the hydrological response variables defined in submethodology M06 (as listed in Table 1) for surface water modelling (Viney, 2016). The surface water hydrological response variables used include changes in low flows, high flows and annual flow due to additional coal resource development. Changes in other hydrological response variables can be accessed online (see www.bioregionalassessments.gov.au/explorer/GLO/hydrologicalchanges). While not explicitly modelled, the potential for additional coal resource development to impact groundwater and surface water quality is reported in this section.
- Section 3.4 considers the impacts on and risks to landscape classes in the zone of potential hydrological change due to additional coal resource development. An aggregated, system-level analysis of potential impacts is possible at the scale of the landscape class. A ‘rule-out’ process identified potentially impacted landscape classes. The impacts on and risks to landscape classes were assessed either quantitatively using the receptor impact models (Hosack et al., 2018), or qualitatively using the qualitative mathematical models developed through expert elicitation (Hosack et al., 2018). Further details on potential hydrological and ecological impacts on individual landscape classes can be accessed online (see www.bioregionalassessments.gov.au/explorer/GLO/landscapes).
- Section 3.5 considers the impacts on and risks to water-dependent assets (McVicar et al., 2015) in the zone of potential hydrological change due to additional coal resource development. The analysis focuses predominantly on asset groups, not on each individual asset. It includes ecological, economic and sociocultural assets. Profiles of potential impacts for individual assets are available online (see www.bioregionalassessments.gov.au/explorer/GLO/assets).
- Section 3.6 assesses the potential hydrological changes and impacts due to the additional coal resource development that was not modelled, Stage 2 of AGL’s Gloucester Gas Project.
- Section 3.7 concludes with key findings and knowledge gaps. Commentary is provided on how to validate and build on this assessment in the future.
The companion product 2.7 receptor impact modelling for the Gloucester subregion (Hosack et al., 2018) summarises the overarching methodology and development of the Gloucester subregion qualitative mathematical models and receptor impact models used to make predictions about the potential impacts on ecosystems reported in Section 3.4. As such it serves as an appendix to this product.
18 December 2018
Summary and download
Product Finalisation date
- 3.1 Overview
- 3.2 Methods
- 3.3 Potential hydrological changes
- 3.4 Impacts on and risks to landscape classes
- 3.5 Impacts on and risks to water-dependent assets
- 3.6 Commentary for coal resource developments that were not modelled
- 3.7 Conclusion
- Contributors to the Technical Programme
- About this technical product