Snowy Hydro Water Operations Reference Report
Total Page:16
File Type:pdf, Size:1020Kb
SNOWY HYDRO WATER OPERATIONS REFERENCE REPORT Snowy Hydro Limited ABN 17 090 574 431 Level 37, AMP Centre, 50 Bridge Street, Sydney NSW 2000, GPO Box 4351 Sydney NSW 2001 Telephone: 02 9278 1888 Facsimile: 02 9278 1879, www.snowyhydro.com.au Snowy Hydro Water Operations Reference Report TABLE OF CONTENTS GLOSSARY.....................................................................................................................................................................1 INTRODUCTION...........................................................................................................................................................4 2. PURPOSE OF THIS DOCUMENT......................................................................................................................4 2.1 STATEMENT OF PURPOSE ..................................................................................................................................4 THE WATER OPERATIONS OF THE SNOWY SCHEME.....................................................................................5 3. SNOWY HYDRO ...................................................................................................................................................5 4. THE SNOWY SCHEME .......................................................................................................................................5 4.1 INTRODUCTION .................................................................................................................................................5 4.2 THE SNOWY -TUMUT DEVELOPMENT ................................................................................................................7 4.3 THE SNOWY -MURRAY DEVELOPMENT .............................................................................................................8 5. THE DESIGN OF THE SNOWY SCHEME .......................................................................................................9 5.1 HIGHLY VARIABLE ANNUAL INFLOWS .............................................................................................................9 5.2 SEASONAL INFLOWS .........................................................................................................................................9 5.3 LARGE STORAGE FOR RELIABLE RELEASES ...................................................................................................10 THE OPERATING PRINCIPLES OF THE SNOWY SCHEME FROM A WATER PERSPECTIVE ..............11 6. THE OPERATING PRINCIPLES OF THE SNOWY SCHEME ...................................................................11 6.1 INTRODUCTION ...............................................................................................................................................11 6.2 CATCHMENT BASED SHARING OF INFLOWS ....................................................................................................11 6.3 REQUIRED ANNUAL RELEASES TO THE WESTERN RIVERS ..............................................................................12 6.4 THE TARGET STORAGE PRINCIPLE .................................................................................................................12 6.5 ABOVE TARGET WATER AND BELOW TARGET WATER ..................................................................................13 6.6 TIMING OF RELEASES ......................................................................................................................................14 6.7 DRY INFLOW SEQUENCE .................................................................................................................................15 THE REGULATORY REGIME GOVERNING WATER AND THE SNOWY SCHEME ..................................16 7. THE SNOWY SCHEME WATER REGULATORY REGIME ......................................................................16 7.1 INTRODUCTION ...............................................................................................................................................16 7.2 THE WATER ACT ............................................................................................................................................16 7.3 THE MURRAY -DARLING BASIN AGREEMENT .................................................................................................16 7.4 SNOWY HYDRO CORPORATISATION ACT ........................................................................................................17 7.5 THE SNOWY WATER INQUIRY OUTCOMES IMPLEMENTATION DEED ..............................................................17 7.6 THE SNOWY WATER LICENCE ........................................................................................................................17 7.7 ANNUAL WATER OPERATING PLANS ..............................................................................................................18 SNOWY HYDRO’S INTERACTIONS WITH OTHERS ON WATER ISSUES ...................................................19 8. INTERACTION WITH OTHERS......................................................................................................................19 8.1 INTRODUCTION ...............................................................................................................................................19 8.2 DWE / MINISTERIAL CORPORATION ..............................................................................................................19 8.3 VICTORIAN DEPARTMENT OF SUSTAINABILITY AND ENVIRONMENT ..............................................................19 8.4 MURRAY DARLING BASIN AUTHORITY ..........................................................................................................19 8.5 NSW STATE WATER CORPORATION ..............................................................................................................19 8.6 WATER CONSULTATION AND LIAISON COMMITTEE .......................................................................................20 8.7 SNOWY HYDRO CONSULTATIVE COMMITTEE .................................................................................................20 8.8 WATER FOR RIVERS .......................................................................................................................................20 8.9 SNOWY SCIENTIFIC COMMITTEE ....................................................................................................................20 Page i Snowy Hydro Water Operations Reference Report SNOWY SCHEME RELEASES, THE ELECTRICITY MARKET AND DOWNSTREAM WATER USE.......21 9. SNOWY SCHEME WATER RELEASES.........................................................................................................21 9.1 THE FOUR DRIVERS TO SNOWY SCHEME WATER RELEASES ..........................................................................21 9.2 THE SNOWY SCHEME AND THE ELECTRICITY MARKET ..................................................................................21 9.3 PROVIDING FLEXIBILITY FOR DOWNSTREAM WATER USERS .........................................................................22 9.4 DOWNSTREAM RE-REGULATION OF SNOWY SCHEME RELEASES ...................................................................22 ENVIRONMENTAL FLOWS AND OTHER RELEASES ......................................................................................24 10. ENVIRONMENTAL FLOWS........................................................................................................................24 10.1 THE GOVERNMENTS ’ COMMITMENTS TO ENVIRONMENTAL FLOWS ...............................................................24 10.2 ENVIRONMENTAL FLOWS AND SNOWY HYDRO ..............................................................................................25 10.3 GOVERNMENT FUNDING FOR WATER EFFICIENCY SAVINGS ..........................................................................26 10.4 THE KEY ELEMENT OF THE ENVIRONMENTAL FLOW REGIME : THE 1:1 RATIO ..............................................27 10.5 ENVIRONMENTAL ENTITLEMENTS AND ANNUAL ALLOCATIONS ....................................................................27 10.6 WHY THE REQUIRED SNOWY RIVER INCREASED FLOW VOLUME MAY BE LESS THAN THE VOLUME OF THE NOMINAL ENVIRONMENTAL ENTITLEMENTS ...............................................................................................................27 10.7 SNOWY RIVER INCREASED FLOWS PRIOR TO THE THIRD ANNIVERSARY OF CORPORATISATION – THE MOWAMBA BORROW ...................................................................................................................................................28 10.8 SNOWY RIVER INCREASED FLOWS FROM THE THIRD ANNIVERSARY OF CORPORATISATION ..........................28 10.9 ENVIRONMENTAL FLOWS – SNOWY RIVER .....................................................................................................28 10.10 ENVIRONMENTAL FLOWS – SNOWY MONTANE RIVERS .............................................................................29 11. OTHER RELEASES .......................................................................................................................................29 11.1 INTRODUCTION ...............................................................................................................................................29 11.2 BASE PASSING FLOWS ....................................................................................................................................29 11.3 RIPARIAN RELEASES .......................................................................................................................................29