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Lake Rotorua Lake Level and Volume Summary of the Rotorua Lakes Prepared by Glenn Ellery, Manager Environmental Data Services Environment Bay of Plenty Internal Report 2004/08 November 2004 5 Quay Street P O Box 364 Whakatane NEW ZEALAND Working with our communities for a better environment Environment Bay of Plenty Contents Chapter 1: Introduction.................................................................................................1 1.1 Overview............................................................................................................1 1.2 Lake Monitoring Sites......................................................................................2 1.3 Lake Volumes...................................................................................................2 1.4 Lake Volume and Rainfall...............................................................................3 Chapter 2: Lake Rotorua..............................................................................................5 2.1 Introduction.......................................................................................................5 2.2 Lake Control Structures ..................................................................................5 2.3 Lake Level Hydrograph...................................................................................6 2.4 Lake Level Distribution....................................................................................7 2.5 Lake Level/Lake Volume Relationship .........................................................8 2.6 Lake Volume Hydrograph...............................................................................9 2.7 Lake Volume Distribution..............................................................................10 2.8 Lake Volume and Rainfall.............................................................................11 Chapter 3: Lake Rotoiti...............................................................................................13 3.1 Introduction.....................................................................................................13 3.2 Lake Control Structures ................................................................................13 3.3 Lake Level Hydrograph.................................................................................14 3.4 Lake Level Distribution..................................................................................14 3.5 Lake Level / Lake Volume Relationship .....................................................16 3.6 Lake Volume Hydrograph.............................................................................17 3.7 Lake Volume Distribution..............................................................................17 3.8 Lake Volume and Rainfall.............................................................................19 Internal Report 2004/08 Lake Level and Volume Summary of the Rotorua Lakes Environment Bay of Plenty Chapter 4: Lake Rotoehu .......................................................................................... 21 4.1 Introduction..................................................................................................... 21 4.2 Lake Control Structures................................................................................ 21 4.3 Lake Level Hydrograph................................................................................ 22 4.4 Lake Level Distribution................................................................................. 22 4.5 Lake Level / Lake Volume Relationship .................................................... 23 4.6 Lake Volume Hydrograph............................................................................ 24 4.7 Lake Volume Distribution............................................................................. 25 4.8 Lake Volume and Rainfall ............................................................................ 26 Chapter 5: Lake Rotoma............................................................................................ 27 5.1 Introduction..................................................................................................... 27 5.2 Lake Control Structures................................................................................ 27 5.3 Lake Level Hydrograph................................................................................ 28 5.4 Lake Level Distribution................................................................................. 28 5.5 Lake Level / Lake Volume Relationship .................................................... 29 5.6 Lake Volume Hydrograph............................................................................ 30 5.7 Lake Volume Distribution............................................................................. 31 5.8 Lake Volume and Rainfall ............................................................................ 32 Chapter 6: Lake Okataina.......................................................................................... 33 6.1 Introduction..................................................................................................... 33 6.2 Lake Control Structures................................................................................ 33 6.3 Lake Level Hydrograph................................................................................ 34 6.4 Lake Level Distribution................................................................................. 34 6.5 Lake Level / Lake Volume Relationship .................................................... 35 6.6 Lake Volume Hydrograph............................................................................ 36 6.7 Lake Volume Distribution............................................................................. 37 6.8 Lake Volume and Rainfall ............................................................................ 38 Lake Level and Volume Summary of the Rotorua Lakes Internal Report 2004/08 Environment Bay of Plenty Chapter 7: Lake Okareka............................................................................................39 7.1 Introduction.....................................................................................................39 7.2 Lake Control Structures ................................................................................39 7.3 Lake Level Hydrograph.................................................................................40 7.4 Lake Level Distribution..................................................................................41 7.5 Lake Level / Lake Volume Relationship .....................................................42 7.6 Lake Volume Hydrograph.............................................................................43 7.7 Lake Volume Distribution..............................................................................44 7.8 Lake Volume and Rainfall.............................................................................45 Chapter 8: Lake Tikitapu............................................................................................47 8.1 Introduction.....................................................................................................47 8.2 Lake Control Structures ................................................................................47 8.3 Lake Level Hydrograph.................................................................................47 8.4 Lake Level Distribution..................................................................................48 8.5 Lake Level / Lake Volume Relationship .....................................................49 8.6 Lake Volume Hydrograph.............................................................................50 8.7 Lake Volume Distribution..............................................................................50 8.8 Lake Volume and Rainfall.............................................................................51 Chapter 9: Lake Tarawera..........................................................................................53 9.1 Introduction.....................................................................................................53 9.2 Lake Control Structures ................................................................................53 9.3 Lake Level Hydrograph.................................................................................54 9.4 Lake Level Distribution..................................................................................54 9.5 Lake Level / Lake Volume Relationship .....................................................55 9.6 Lake Volume Hydrograph.............................................................................56 9.7 Lake Volume Distribution..............................................................................57 9.8 Lake Volume and Rainfall.............................................................................58 Internal Report 2004/08 Lake Level and Volume Summary of the Rotorua Lakes Environment Bay of Plenty Chapter 10: Lake Rotokakahi.................................................................................. 59 10.1 Introduction..................................................................................................... 59 10.2 Lake Control Structures................................................................................ 59 10.3 Lake Level Hydrograph................................................................................ 60
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