Territory Stories

Development of a Groundwater Model for the Western Davenport Plains

Details:

Title

Development of a Groundwater Model for the Western Davenport Plains

Creator

Knapton, Anthony; CloudGMS Pty Ltd

Commissioned by

Northern Territory. Department of Environment, Parks and Water Security

Collection

E-Publications; E-Books; PublicationNT; WRD Technical Report 27/2017

Date

2018-03

Location

Western Davenport Water Control District

Abstract

CloudGMS has been commissioned by DENR to develop a numerical groundwater model of the aquifers within the central area of the WDWCD to improve confidence in the sustainability of the groundwater resources, as this is the area within the WCD with greatest potential for intensive development.

Notes

Made available by via Publications (Legal Deposit) Act 2004 (NT); Prepared for Dept Environment and Natural resources

Table of contents

Executive summary -- 1 Background -- 2 Physical -- 3 Available data -- 4 Conceptual model -- 5 Model design & construction -- 6 Parameter estimation -- 7 Water balances -- 8 Sensitivity analysis -- 9 Predictive scenarios -- 10 Conclusions -- 11 Reference -- 12 Document history and version control -- Appendix A - Groundwater level hydrographs - Appendix B - Alek range horticultural farm sub-regional modelling

Language

English

Subject

Groundwater; Northern Territory; Western Davenport Water Control District; Conceptual mode

Publisher name

Northern Territory Governmnet

Place of publication

Palmerston

Edition

version 2.0

Series

WRD Technical Report 27/2017

Format

ix, 127 pages : colour illustration and maps ; 30 cm

File type

application/pdf

ISBN

9781743502976

Use

Attribution International 4.0 (CC BY 4.0)

Copyright owner

Northern Territory Government

License

https://creativecommons.org/licenses/by/4.0/

Related links

https://hdl.handle.net/10070/842058 [LANT E-Publications: Development of a Groundwater Model for the Western Davenport Plains, version 1.1]

Parent handle

https://hdl.handle.net/10070/858845

Citation address

https://hdl.handle.net/10070/858846

Page content

Western Davenport WCD Groundwater Model (v2.0) Model Design & Construction CloudGMS 61 5.1.7. SZ Computational layers In this study the computational layers are coincident with the geological layers and the model settings for the saturated zone computational layers are presented in Table 13. Table 13 Parameters used to define the computational layers in the MIKE SHE model. Computational layer settings Value / range Unit Defined by geological layers Minimum layer thickness 10 [m] Lower layer Arith. mean Sat. thick. log mean cond. - Strictly Unconfined Fixed head outer boundary 310 [mAHD] Initial potential head -9.5 [mBGL] 5.1.8. Outer boundary conditions The outer boundary conditions are defined as line segments between two boundary points. There are 4 outer boundary conditions available in MIKE SHE. Zero flux - This is a no-flow boundary, which is the default. Fixed Head - This boundary prescribes a head in the boundary cell. The head can be fixed at a prescribed value, fixed at the initial value from the initial conditions, or assigned to a time series file. Flux - This boundary describes a constant or time varying flux across the outer boundary of the model. A time varying flux can be specified as a mean step-accumulated discharge (e.g. m3/s) or as a step-accumulated volume (e.g. m3). A positive value implies an inflow to the model cells. Gradient - This boundary describes a constant or time varying gradient between the node on the outer boundary and the first internal node. The boundaries to the north, east and south coincide with surface water divides and are assumed to be no-flow boundaries. The majority of the western boundary is aligned with a regional stream line and is represented as a no-flow boundary condition from physical symmetry. The northern extent of the western boundary corresponds to the regional groundwater outflow and is assumed to be a fixed head boundary. The locations of the boundary conditions at the extents of the model domain are depicted in Figure 5-5. It is not best practise to invoke constant head boundaries close to the area of interest, however, the distance between the main area of interest and the northern boundary is sufficient (> 50km) that the influence of this boundary does not impact on the processes in the area of investigation.