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) Contents CloudGMS vi 9.7. Predictive uncertainty ..................................................................................................... 107 9.7.1. Hydraulic parameters ................................................................................................. 107 9.7.2. Storage depletion ....................................................................................................... 108 9.7.3. Propagation of drawdowns ........................................................................................ 108 9.8. Summary ....................................................................................................................... 108 10 Conclusions ....................................................................................................................... 109 10.1. Overall outcomes ........................................................................................................... 109 10.2. Aquifer occurrence and geometry .................................................................................. 109 10.3. System sustainability ...................................................................................................... 110 11 References ......................................................................................................................... 111 12 Document history and version control ................................................................................ 114 Appendix A Groundwater level hydrographs ........................................................................... 115 Appendix B Alekerange horticultural farm sub-regional modelling ........................................... 121 List of Figures Figure 1-1 Groundwater modelling process after Barnett et al, (2012) ................................................ 3 Figure 2-1 Location of the study area. ................................................................................................ 8 Figure 2-2 Average monthly rainfall compared to average max and min temperatures and average monthly rainfall compared to monthly potential evaporation for the period 1900-2014 (SILO Data Drill). ............................................................................................................................................ 9 Figure 2-3 Extent of the AGT 2007 modelling study compared to the current study model domain. . 12 Figure 3-1 Annual SILO rainfall totals with a trace of mass residual to show longer term trends in the rainfall (1900-2016). ................................................................................................................... 13 Figure 3-2 Southern oscillation index highlighting positive SOI values (greater than +8), which correspond to La Nia events. La Nia events are often associated with wetter than normal conditions across eastern and northern Australia. ...................................................................... 14 Figure 3-3 SRTM derived topography of the Western Davenport Plains study area with derived drainage and watershed boundary. ........................................................................................... 15 Figure 3-4 Schematic map of southern Wiso and Georgina basins showing the locations of Palaeozoic depositional troughs. Lander Trough, along southern Wiso Basin margin, is on trend with Dulcie trough of the Georgina Basin to southeast, both of which are separated from Proterozoic rocks of Aileron Province by a series of thrust fault systems. ................................................................... 17 Figure 3-5 Distribution and thickness of Cenozoic sediments in the WDWCD after Tickell, (2014). ... 24 Figure 3-6 Surface geology derived from the 1:1000000 scale geology coverage and the location of the geological cross-section from Haines, et al., (1990). ............................................................ 26 Figure 3-7 Geological cross-sections after Haines, et al., 1990. The locations of the cross-sections are presented in Figure 3-6. ...................................................................................................... 27 Figure 3-8 Hydrogeological mapping within the Western Davenport basin (after Tickell, 2014). ........ 30 Figure 3-9 Hydrogeological model of the Western Davenport WCD based on geological sections (Haines, Bagas, Wyche, Simons, & Morris, 1990) and hydrogeological mapping (Tickell, 2014). 31 Figure 3-10 Hydrogeological section derived from the hydrogeological block model (after Tickell, 2014). ........................................................................................................................................ 32 Figure 3-11 Potentiometric surface contours (interval = 10 metres) and location of SWL data points (after Tickell, 2014). ................................................................................................................... 33 Figure 3-12 Locations of monitoring bores in the Western Davenport WCD, showing number of observations. ............................................................................................................................. 35 Figure 3-13 Distribution of transmissivity values from pumping tests conducted in the Western Davenport WCD compared to hydrogeological units (modified from Tickell, 2014). .................... 38