The impact and risk analysis (Box 8) investigated how hydrological changes due to additional coal resource development may affect water-dependent assets, such as bores, wetlands or heritage sites.
A total of 2660 water-dependent assets (listed in Dataset 10 and Bioregional Assessment Programme (2017)) were identified for the subregion (Table 3):
- 2215 ecological assets, including 23 groundwater assets, 1688 surface water assets (including the 177 springs described earlier) and 504 vegetation assets, including GDEs, riparian areas, protected reserves, and potential habitat of threatened species and communities
- 310 economic assets, including 127 groundwater assets (which include multiple bores) and 183 surface water assets
- 135 sociocultural assets, including cultural assets (50 heritage sites and 59 Indigenous sites) and social assets (26 recreation areas). There were 56 Indigenous cultural assets identified through consultation with Indigenous knowledge holders and 3 were nominated by the broader community; some of their locations were not provided.
Potential impacts on water-dependent assets were assessed by overlaying their extent on the zone of potential hydrological change (Table 3).
Of the 2660 water-dependent assets nominated by the community for the subregion, most (2495) are very unlikely to be impacted because they experience less than 0.2 m drawdown due to additional coal resource development. Key finding 8:
Table 3 Water-dependent assets in the assessment extent and the zone of potential hydrological change
aNumbers for economic assets are not individual bores; they are water access entitlements that could include one or multiple bores.
bOf the 135 sociocultural assets, 35 Indigenous cultural assets are cultural values associated with animals and plants that do not have geographic location information, which means they cannot be specifically assessed for potential impacts due to additional coal resource development. See Table 29 in the impact and risk analysis (Holland et al., 2017) for more details.
Data: Bioregional Assessment Programme (Dataset 9)
Ecological assets
Which ecological assets are very unlikely to be impacted?
No protected reserves, parks, bird habitats or key environmental assets are within the zone of potential hydrological change. Also, none of the 882 water-dependent assets classified as ‘Floodplain’, ‘Lake, reservoir, lagoon or estuary’, ‘Marsh, sedgeland, bog, spring or soak’ or ‘Waterhole, pool, rock pool or billabong’ are within the zone. This includes the 177 springs assessed in ‘Which landscape groups are very unlikely to be impacted?’.
Which ecological assets are potentially impacted?
Of the 2215 ecological water-dependent assets in the assessment extent, 115 are subject to potential hydrological change due to additional coal resource development. This does not mean that these 115 assets are definitely impacted – finer resolution models are required for that local-scale assessment of impact. At this stage, however, there is not compelling evidence to rule out impacts.
Forty-one ecosystems are in an area where there is at least a 5% chance of drawdown exceeding 0.2 m due to additional coal resource development. This includes the potential habitats of 4 threatened ecological communities and 18 species listed under the Commonwealth’s Environment Protection and Biodiversity Conservation Act 1999; an additional 6 endangered regional ecosystems and potential habitats of 11 species listed under Queensland’s Nature Conservation Act 1992; and 2 riparian vegetation assets. Key finding 9:
Water-dependent assets that are potentially impacted by drawdown due to additional coal resource development include:
- Groundwater feature (subsurface): 11 aquifers or geological layers (including GAB recharge areas, sandstone aquifers and a groundwater flow system) and part of 1 asset (252 of the more than 13,000 groundwater production bores in the Condamine Alluvium)
- Surface water feature: 18 streams, including parts of the Auburn River in the Burnett river basin; Downfall, Juandah and Roche creeks in the Fitzroy river basin; Upper Oakey Creek in the Condamine river basin; and 11 wetlands in the Balonne, Burnett, Condamine and Fitzroy river basins
- Vegetation – Groundwater-dependent ecosystem: 17 assets described in the National atlas of groundwater dependent ecosystems (GDE Atlas) (Bureau of Meteorology, 2012) and 16 assets identified by the Queensland Government GDE mapping. This includes 6 vegetation communities associated with groundwater discharged to the surface as springs or baseflow to rivers and 11 vegetation communities that interact with a groundwater system beneath the surface described in the GDE Atlas
- Vegetation – Habitat (potential species distribution):39 water-dependent assets, including:
- 4 threatened ecological communities: ‘Brigalow’, ‘Semi-evergreen vine thickets’, ‘Weeping Myall Woodlands’ and ‘Natural grasslands on basalt and fine-textured alluvial plains’
- 18 species listed under the Commonwealth’s Environment Protection and Biodiversity Conservation Act 1999:
- birds: black-faced monarch, cattle egret, fork-tailed swift, great egret, red goshawk, satin flycatcher, squatter pigeon (southern), star finch (eastern) and the white-bellied sea-eagle
- mammals: grey-headed flying-fox and koala
- plants: Belson's panic, blotched sarcochilus, finger panic grass and stream clematis
- reptiles: Dunmall's snake, five-clawed worm-skink and yakka skink
- 11 species and 6 endangered regional ecosystems listed under Queensland’s Nature Conservation Act 1992
- Vegetation – Riparian vegetation:2 water-dependent assets, excluding the riparian vegetation along the Lower Balonne System identified as a Murray–Darling Basin Authority Key Environmental Asset (KEA).
See Section 3.5.2 in the impact and risk analysis (Holland et al., 2017) for more details, including a literature review of the nature of the water dependency of these assets.
Economic assets
Which economic assets are very unlikely to be impacted?
Hydrological changes due to additional coal resource development are very unlikely to impact 296 of the 310 economic assets (Table 3 and Table 4). As seen in Table 4, these 296 unimpacted economic assets include 9827 bores, 182 surface water assets and all 13 water supply and monitoring infrastructure assets, including Atkinsons Dam, Bill Gunn Dam, Clarendon Dam, 3 weirs and 13 borefields (Bioregional Assessment Programme, 2017).
Which economic assets are potentially impacted?
There is at least a 5% chance that 163 bores experience greater than 0.2 m drawdown due to additional coal resource development. The 163 bores are part of 13 economic assets that comprise 7 water access rights and 6 basic water rights (stock and domestic). Of these 163 bores, it is very likely that additional drawdown exceeds 5 m in 17 bores located near the proposed New Acland Stage 3 coal mine pits, including 5 bores that access water from the near-surface aquifer and 12 bores that access water from the Walloon Coal Measures. Key finding 10:
There are 9990 individual bores within the assessment extent (Table 4). Of the 163 bores in the zone of potential hydrological change, 20 water access rights and 6 basic water rights (stock and domestic) have a greater than 50% chance of exceeding 5 m of drawdown due to additional coal resource development (Figure 11). The modelled open-cut mine pits for the New Acland Stage 3 coal mine and The Range coal mine contain 9 of these 163 economic bores. The larger values of maximum drawdown occur in bores close to the mines or within the modelled pits, which cover around 40 km2, and the maximum drawdown in these bores occurs in the years immediately following mining activity (see Figure 25 and Figure 26 in Janardhanan et al. (2016)). Smaller values of maximum drawdown are observed in bores located further from the mines and occur in later years when the drawdown propagates to these bores.
The bores are managed by the Condamine and Balonne water plan and the Eastern Downs, Surat, Surat East and Surat North groundwater management units in the Water Resource (Great Artesian Basin) Plan 2006. No bores in the zone access groundwater in the deeper Bowen Basin aquifers underlying the GAB (see Table 33 in the impact and risk analysis (Holland et al., 2017)).
One water access right associated with a surface water management zone falls within the zone of potential hydrological change near The Range coal mine in the headwaters of Downfall Creek. As surface water modelling was not carried out in this assessment (Box 3), the potential impacts on this water access right were not assessed further.
Table 4 Number of economic water-dependent elements and assets in the assessment extent and zone of potential hydrological change
aAssets are combinations of one or more elements (individual spatial features – points, lines and polygons). For example, an asset might be a collection of bores.
Data: Bioregional Assessment Programme (Dataset 9)
Most of this synthesis focuses on the zone of potential hydrological change in the regional watertable, but here the same threshold (Box 5) is used to define zones for deeper layers that bores access. Median is a 50% chance (Box 6). Baseline drawdown is the maximum difference in drawdown under the baseline relative to no coal resource development (Box 4). Additional drawdown is the maximum difference in drawdown between the coal resource development pathway (CRDP) and baseline, due to additional coal resource development.
Data: Bioregional Assessment Programme (Dataset 8, Dataset 9, Dataset 11, Dataset 16)
Sociocultural assets
Which sociocultural assets are very unlikely to be impacted?
Sociocultural assets that fall outside the zone of potential hydrological change include 50 heritage sites, 3 Indigenous sites and 26 recreation areas, including national parks and areas of remnant vegetation. These have a less than 5% chance of impacts due to additional coal resource development.
Separate reports on Indigenous water assets in the Queensland and NSW parts of the Maranoa-Balonne-Condamine subregion contributed to this assessment (Constable and Love, 2015). Consultation with Traditional Owners in the Maranoa-Balonne-Condamine subregion identified an additional 56 Indigenous assets, which were included in the water-dependent asset register (Bioregional Assessment Programme, 2017) and used for the impact and risk analysis. Of these, 35 are cultural values associated with animals and plants that do not have geographic location information, which means they cannot be specifically assessed for impacts due to additional coal resource development.
Which sociocultural assets are potentially impacted?
The Barakula State Forest, near Miles in Queensland, is the sole sociocultural asset located in the area where drawdown due to additional coal resource development exceeds 0.2 m in the regional watertable with a greater than 5% chance. It is very likely that 21 km2 or 0.7% of the 3092 km2 forest experiences more than 0.2 m of drawdown due to additional coal resource development. Key finding 11:
Additional drawdown in the regional watertable in excess of 2 m is not very likely within the forest and is very unlikely to include more than 6 km2 of the forest.
Barakula State Forest is located along the eastern edge of the zone of potential hydrological change near The Range coal mine (Figure 7 and Figure 9). It is water dependent based on the presence of floodplain and wetland areas and shallow groundwater within its extent. However, finer resolution models are better placed to assess potential impacts at a local scale.
FIND MORE INFORMATION
Explore assets in more detail at www.bioregionalassessments.gov.au/explorer/MBC/assets
Description of the water-dependent asset register, product 1.3 (Mitchell et al., 2015)
Water-dependent asset register (Bioregional Assessment Programme, 2017)
Impact and risk analysis, product 3-4 (Holland et al., 2017)
Compiling water-dependent assets, submethodology M02 (Mount et al., 2015)
Analysing impacts and risks, submethodology M10 (Henderson et al., 2017)
Impact and risk analysis database (Dataset 9)
Asset spatial overlay by assessment unit (Dataset 16)
Summary of groundwater drawdown by assessment unit (Dataset 11)
