Development of a Groundwater Flow Model - Berry Springs
Knapton, Anthony
E-Publications; E-Books; PublicationNT; 17/2016
2016
Berry Springs
Made available via the Publications (Legal Deposit) Act 2004 (NT).
Table of Contents -- List of Figures -- List of Tables -- Acknowledgements -- Glossary of Terms -- Executive Summary -- 1 Introduction -- 1.1 Background -- 1.1 Aim of the study -- 2 Site Description -- 2.1 Study area location -- 2.2 Climate -- 2.2.1 Rainfall data -- 2.2.2 Evaporation data -- 2.3 Hydrology -- 2.4 Land use -- 2.5 Groundwater extraction -- 2.6 Water quality -- 3 Hydrogeology -- 3.1 Geological formations -- 3.1.1 Mount Bonnie Formation (Pso) -- 3.1.2 Unnamed Dolostone Unit (Psd): Berry Springs Dolostone -- 3.1.3 Burrell Creek Formation (Pfb) -- 3.1.4 Depot Creek Formation (Ptd) -- 3.1.5 Petrel Formation (JKp) -- 3.1.6 Darwin Member (Kld) -- 3.2 Geological structure -- 3.3 Aquifer characteristics -- 3.3.1 Hydraulic conductivity -- 3.3.2 Storage coefficient -- 4 Groundwater hydrology -- 4.1 Groundwater flow -- 4.2 Recharge -- 4.2.1 Water balance method -- 4.2.2 Water table fluctuation method -- 4.2.3 Spring discharge -- 4.2.4 Evapotranspiration -- 4.3 Rainfall-runoff modelling -- 4.4 Predicted natural conditions compared to recent observed flows -- 4.5 Groundwater chemistry -- 5 Available data -- 5.1 Climate data -- 5.2 SRTM digital terrain model -- 5.3 Geological data -- 5.4 Groundwater level data -- 5.4.1 Steady state groundwater levels -- Berry Springs Groundwater Flow Model -- 5.4.2 Time series groundwater levels -- 5.5 River discharge data -- 5.5.1 Manual gauging data -- 5.5.2 Continuous recorder data -- 5.6 Pumping data -- 5.7 Data gaps -- 6 Groundwater flow model development -- 6.1 What is a groundwater flow model? -- 6.2 Conceptual model -- 6.3 Modelling approach -- 6.4 Model package -- 6.5 Model mesh geometry -- 6.5.1 Mesh design -- 6.5.2 Mesh generation -- 6.6 Material properties -- 6.7 Fracture flow -- 6.8 Boundary conditions -- 6.8.1 Recharge and Areal ET Flux -- 6.8.2 Constant head BC values -- 6.9 Pumping data -- 6.10 FEFLOW settings -- 6.10.1 Problem class -- 6.10.2 Temporal and control data -- 7 Calibration -- 7.1 Steady state finite element model -- 7.1.1 Steady state model results -- 7.2 Transient finite element model -- 8 Scenarios -- 8.1 Water balance assessment -- 8.2 Scenario A – Historic climate without pumping -- 8.2.1 Water balance under historic climate -- 8.3 Scenario B – Historic climate with current pumping estimates -- 8.3.1 Pumping estimate methodology -- 8.3.2 Water balance under historic climate and current pumping -- 8.3.3 Impacts of pumping on groundwater discharge at Berry Springs -- 8.3.4 Flow duration -- 9 Results and discussion -- 9.1 Measurable impacts -- 9.1.1 Reduced dry season flows -- 9.1.2 Recession slope of dry season flows -- 9.1.3 Groundwater levels -- 9.2 Rainfall, recharge & minimum flows analysis -- 9.3 Impacts of pumping based on zones -- 10 Conclusions -- 10.1 Key performance indicators -- 11 References -- Appendix A - Groundwater level hydrographs -- Appendix B - Calibrated transient model results
English
Berry Springs Dolostone; Berry Springs aquifer System; Groundwater Flow Model
Department of Land Resource Management
Darwin
17/2016
72 pages : colour illustration and maps ; 30 cm.
application/pdf.
9781743501092
Check within Publication or with content Publisher.
https://hdl.handle.net/10070/272355
https://hdl.handle.net/10070/428025
Berry Springs Groundwater Flow Model Page 5 of 72 Appendix C MIKE SHE 1D recharge modelling .............................................................................. 63 1.2 ...... Simplified Macro-pore Flow (bypass flow) ............................................................................ 64 1.3 ...... Model Inputs......................................................................................................................... 64 1.3.1 ........ Climatic data ................................................................................................................. 64 1.3.2 ........ Soil data ........................................................................................................................ 65 1.3.3 ........ Vegetation data ............................................................................................................. 65 1.3.4 ........ Calibration ..................................................................................................................... 66 1.3.5 ........ Nash Sutcliffe efficiency coefficient ................................................................................ 67 Appendix D FEFLOW Model Optimisation Using Parameter ESTimation (PEST) ....................... 68 1.4 ...... Introduction .......................................................................................................................... 68 1.5 ...... Parameter estimation process .............................................................................................. 68 1.6 ...... Estimated parameters .......................................................................................................... 69 1.7 ...... Objective function ................................................................................................................. 69 1.8 ...... Parameter ESTimation results .............................................................................................. 69 1.9 ...... Sensitivity Analysis ............................................................................................................... 70 1.9.1 ........ Pumping data ................................................................................................................ 71 Appendix E Formulation of discrete feature fracture flow ............................................................ 72 List of Figures Figure 1 Location of the Berry Springs dolomite aquifer system .................................................................................. 12 Figure 2 a) Annual rainfall and b) cumulative mass residual curve of rainfall for Berry Springs area demonstrating long term trends in rainfall from 1900 - 2016. ..................................................................................................................... 14 Figure 3 Annual evaporation for Berry Springs area. ............................................................................................................ 14 Figure 4 Land use in the Berry Springs region showing distribution of bores with registration numbers. ............................. 16 Figure 5 Cumulative bore count in the Berry Springs aquifer. ...................................................................................... 17 Figure 6 Water quality data for Berry Springs Main Pool showing E.Coli and Enterococci counts per 100ml. ............... 17 Figure 7 Hydrogeology of the Berry Springs region and cross-section through Berry Springs (Verma, 1995). ............... 19 Figure 8 Groundwater and streamflow monitoring of the Berry Springs region. .................................................................. 21 Figure 9 Comparison of daily rainfall manual groundwater levels and logger data for RN029016 from 2005 - 2010. ... 22 Figure 10 Comparison of cumulative mass residual, manual groundwater levels and logger data for RN029016 from 1993 - 2010. ................................................................................................................................................................. 23 Figure 11 Berry Springs spring complex located along Berry Creek (after Tickell). ......................................................... 24 Figure 12 Graphical comparison of simulated and observed flows at G8150027. ........................................................... 25 Figure 13 Observed (period 1950-1970) and simulated flow (period 1900-2010) duration curves for March Fly Weir (G8150027). ................................................................................................................................................................. 25 Figure 14 NAM results for period 1980-2012, prior to 2000 the available gaugings show a close match to the simulated results, recent gaugings suggest groundwater discharge is lower than expected. ....................................................... 26 Figure 15 Difference between the observed and simulated discharge assuming no groundwater extraction in the model. The increased difference between observed and simulated results in 2010 are attributed to unaccounted for groundwater extraction. .............................................................................................................................................. 26 Figure 16 Digital elevation model of the Berry Springs area ........................................................................................... 29 Figure 17 Manual gauged data for March Fly Weir (G8150027) with linear fits demonstrating the recession in dry season groundwater discharge. ................................................................................................................................... 31 Figure 18 Historic discharge data at G8150027. Gauged flows have been conducted 27/07/1952 7/12/1996. Continuous record exists from 2/11/1960 24/08/1981. ............................................................................................ 31 Figure 19 Conceptual model of the Berry Springs aquifer system. ................................................................................. 34 Figure 20 Finite element mesh geometry used in Berry Springs groundwater model. .................................................... 37 Figure 21 Estimated historic monthly pumping (expressed as kL/d) applied to the Berry Springs groundwater model .. 39 Figure 22 Steady state heads RMS error (2.99 m) is approximately the same order as the error associated with the SRTM elevation data. .................................................................................................................................................. 41 Figure 23 Location of pumping nodes applied to slice 3 of the FE model. ...................................................................... 45 Figure 24 Comparison of simulated discharge (m 3 /d) at Berry Springs spring complex under historic climatic conditions with no pumping and estimated current pumping for the period a) 1900-1950 and b) 1950-2010. ............................. 47