2.6.2.3.3 Design and implementation


2.6.2.3.3.1 Modelling time and stress period setup

The transient stage of the groundwater model spanned a total simulation period of 120 years from 1983 to 2102 (Figure 11). The available observations during the historical period from 1983 to 2012 provided constraints on model parameters, such as hydraulic conductivity and boundary-related parameters. During the prediction period that spanned a period of 90 years from 2013 to 2102, the 95 CSG wells were gradually activated from 2018 to 2036 after which no additional wells were activated. These wells continued to extract water until the target water pressure (equilant to a water level of 35 m above the top of the Walloon Coal Measures) was realised. Monthly stress periods were adopted throughout the simulation to provide monthly change of baseflow required by the surface water model. This led to a total number of 1441 stress periods, including the first stress period, which represented a steady-state simulation prior to the transient modelling.

Figure 11

Figure 11 Time discretisation of the groundwater model

CSG = coal seam gas

2.6.2.3.3.2 Grid discretisation

The model domain shown in Figure 10 was discretised into 248 rows and 184 columns resulting in 33,352 active cells in every layer. Grid spacing varied from 200 m by 200 m inside the additional coal resource development domain to 800 m by 800 m outside the domain. The model grid is orientated in the north–south direction without any rotation.

Last updated:
11 July 2017
Thumbnail images of the Clarence-Moreton bioregion

Product Finalisation date

20 October 2016
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