Instream salinity models of NSW tributaries in the Murray-Darling Basin Volume 3 – Namoi River Salinity Integrated Quantity and Quality Model Publisher NSW Department of Water and Energy Level 17, 227 Elizabeth Street GPO Box 3889 Sydney NSW 2001 T 02 8281 7777 F 02 8281 7799 [email protected] www.dwe.nsw.gov.au Instream salinity models of NSW tributaries in the Murray-Darling Basin Volume 3 – Namoi River Salinity Integrated Quantity and Quality Model April 2008 ISBN (volume 2) 978 0 7347 5990 0 ISBN (set) 978 0 7347 5991 7 Volumes in this set: In-stream Salinity Models of NSW Tributaries in the Murray Darling Basin Volume 1 – Border Rivers Salinity Integrated Quantity and Quality Model Volume 2 – Gwydir River Salinity Integrated Quantity and Quality Model Volume 3 – Namoi River Salinity Integrated Quantity and Quality Model Volume 4 – Macquarie River Salinity Integrated Quantity and Quality Model Volume 5 – Lachlan River Salinity Integrated Quantity and Quality Model Volume 6 – Murrumbidgee River Salinity Integrated Quantity and Quality Model Volume 7 – Barwon-Darling River System Salinity Integrated Quantity and Quality Model Acknowledgements Technical work and reporting by Perlita Arranz, Richard Beecham, and Chris Ribbons. This publication may be cited as: Department of Water and Energy, 2008. Instream salinity models of NSW tributaries in the Murray-Darling Basin: Volume 3 – Namoi River Salinity Integrated Quantity and Quality Model, NSW Government. © State of New South Wales through the Department of Water and Energy, 2008 This work may be freely reproduced and distributed for most purposes, however some restrictions apply. Contact the Department of Water and Energy for copyright information. Disclaimer: While every reasonable effort has been made to ensure that this document is correct at the time of publication, the State of New South Wales, its agents and employees, disclaim any and all liability to any person in respect of anything or the consequences of anything done or omitted to be done in reliance upon the whole or any part of this document. DWE 07_089_3 In-stream salinity models of NSW tributaries in the Murray-Darling Basin Volume 3: Namoi River Salinity Integrated Quantity and Quality Model Contents Page 1 Introduction .......................................................................................................................................14 1.1. purpose of report..........................................................................................................14 1.1.1. Report structure ...............................................................................................14 1.1.2. Related reports.................................................................................................15 1.2. Historical background to work ....................................................................................15 1.2.1. 1988 Salinity and Drainage Strategy...............................................................15 1.2.2. 1997 Salt trends...............................................................................................16 1.2.3. 1999 Salinity Audit .........................................................................................16 1.2.4. 2006 Salinity Audit .........................................................................................16 1.3. Current policy framework............................................................................................17 1.3.1. MDBC Integrated Catchment Management....................................................17 1.3.2. Murray-Darling Basin Ministerial Council Cap on water diversions..............17 1.3.3. Murray-Darling Basin Ministerial Council Basin Salinity Management Strategy......................................................................................17 1.3.4. Catchment Action Plans ..................................................................................18 1.3.5. NSW Water Sharing Plans ..............................................................................19 1.3.6. NSW Salinity Strategy ....................................................................................19 1.3.7. NSW Environmental Services Scheme ...........................................................19 1.3.8. CMA Incentive schemes .................................................................................19 1.4. DWE Model framework ..............................................................................................20 1.4.1. Objectives of modelling ..................................................................................20 1.4.2. Modelling requirements ..................................................................................20 1.4.3. Strengths and Limitations................................................................................21 1.5. Staged Model Development ........................................................................................23 1.5.1. Stage 1: Model QA and Data Audit ................................................................23 1.5.2. Stage 2: Initial model development and data and model evaluation ...............23 1.5.3. Stage 3: Model calibration and scenario modelling ........................................24 2. The Namoi-Peel System...........................................................................................................25 2.1. Physical features of the catchment...............................................................................25 2.1.1. General ............................................................................................................25 2.1.2. Stream network ...............................................................................................27 2.1.3. Hydrometeorology...........................................................................................28 2.1.4. Groundwater interactions. ...............................................................................31 2.1.5. Vegetation and land use ..................................................................................33 2.2. Water resource management........................................................................................34 2.2.1. Peel River system water resource management ..............................................34 1 | NSW Department of Water and Energy, April 2008 In-stream salinity models of NSW tributaries in the Murray-Darling Basin Volume 3: Namoi River Salinity Integrated Quantity and Quality Model 2.2.2. Namoi River system water resource management ..........................................35 2.3. Salinity in catchment ...................................................................................................35 3. Salinity data .............................................................................................................................37 3.1. Available data ..............................................................................................................37 3.2. Data used for inflow estimates and model evaluation .................................................38 3.2.1. Exploratory analysis of data............................................................................38 4. The Namoi & Peel IQQMs ......................................................................................................43 4.1. Quantity Model............................................................................................................43 4.1.1. Peel system......................................................................................................43 4.1.2. Namoi system..................................................................................................45 4.1.3. Inflows and calibration....................................................................................45 4.1.4. Storages ...........................................................................................................46 4.1.5. Extractive demands .........................................................................................47 4.1.6. In-stream demands ..........................................................................................47 4.1.7. Peer Review.....................................................................................................47 4.2. Quality Assurance of quality model ............................................................................53 4.2.1. QA Test 1: Update base quantity model..........................................................53 4.2.2. QA Test 2: Initialise salinity module with zero salt load ................................53 4.2.3. QA Test 3: Constant flow and concentration ..................................................54 4.2.4. QA Test 4: Variable flow and constant concentration ....................................54 4.2.5. QA Test 5: Flow pulse with constant concentration .......................................55 4.2.6. QA Test 6: Salt pulse with constant flow........................................................55 4.3. Quality assurance conclusions.....................................................................................56 5. Salt inflow estimate and evaluation .........................................................................................57 5.1. Initial estimate .............................................................................................................57 5.2. Evaluation method.......................................................................................................60