2016 Pilot Waikato River Report Card: Methods and Technical Summary Prepared for Waikato River Authority March 2016 2015 Pilot Waikato River Report Card: Methods and Technical Summary Prepared by : Bruce Williamson (Diffuse Sources) John Quinn (NIWA) Erica Williams (NIWA) Cheri van Schravendijk-Goodman (WRRT) For any information regarding this report please contact: National Institute of Water & Atmospheric Research Ltd PO Box 11115 Hamilton 3251 Phone +64 7 856 7026 NIWA CLIENT REPORT No: HAM2016-011 Report date: March 2016 NIWA Project: WRA14203 Quality Assurance Statement Reviewed by: Dr Bob Wilcock Formatting checked by: Alison Bartley Approved for release by: Bryce Cooper Photo: Waikato River at Wellington Street Beach, Hamilton. [John Quinn, NIWA] 2015 Pilot Waikato River Report Card: Methods and Technical Summary Contents Summary ............................................................................................................................ 9 Reflections from the Project Team ..................................................................................... 12 1 Introduction ............................................................................................................ 18 1.1 Report Cards ........................................................................................................... 18 1.2 2015 Pilot Waikato River Report Cards .................................................................. 20 1.3 Purpose of this Technical Summary ........................................................................ 28 2 Experience ............................................................................................................... 29 2.1 Introduction ............................................................................................................ 29 2.1.1 Recreation Attributes of Water Bodies ................................................... 29 2.1.2 Amenity Values and Access ..................................................................... 29 2.1.3 Social and Recreational Values and Beliefs ............................................. 30 2.2 Scoring Experience .................................................................................................. 30 2.2.1 Physical Access ........................................................................................ 31 2.2.2 Navigation ............................................................................................... 33 2.2.3 Rubbish .................................................................................................... 35 2.2.4 Signage .................................................................................................... 38 2.2.5 Human Sewage Discharges ..................................................................... 40 2.2.6 Water Clarity (Black Disk and Secchi Disk Visibility) ................................ 43 2.2.7 E.coli ........................................................................................................ 44 2.2.8 Blue Green Algae ..................................................................................... 47 2.3 Experience Taura scoring ........................................................................................ 48 2.4 Other indicators considered but discarded ............................................................ 50 2.5 Future scoring ......................................................................................................... 50 3 Ecological Integrity ................................................................................................... 52 3.1 Introduction ............................................................................................................ 52 3.2 Scoring Ecological Integrity ..................................................................................... 52 3.2.1 Physico-chemical stressors ...................................................................... 52 3.2.2 Riparian Condition ................................................................................... 63 3.2.3 Aquatic Plants Lakes and Mainstem ........................................................ 73 3.2.5 Macroinvertebrates ................................................................................. 80 3.2.6 Fish .......................................................................................................... 82 3.2.7 Water Birds .............................................................................................. 85 3.2.8 Connectivity ............................................................................................. 90 2015 Pilot Waikato River Report Card: Methods and Technical Summary 3.3 Ecological Integrity Taura scores ............................................................................ 94 3.4 Other Indicators considered then discarded .......................................................... 95 3.5 Future Scoring ......................................................................................................... 95 4 Kai ........................................................................................................................... 98 4.1 Introduction ............................................................................................................ 98 4.2 Scoring Kai ............................................................................................................... 98 4.2.1 Tuna ......................................................................................................... 98 4.2.2 Whitebait ............................................................................................... 102 4.2.3 Kaaeo / Kākahi ....................................................................................... 106 4.2.4 Kōura ..................................................................................................... 108 4.2.5 Piharau .................................................................................................. 111 4.2.6 Trout ...................................................................................................... 113 4.2.7 Waterfowl .............................................................................................. 114 4.3 Kai Taura scores .................................................................................................... 115 4.4 Future Scoring ....................................................................................................... 116 5 Water Quality ........................................................................................................ 119 5.1 Introduction .......................................................................................................... 119 5.2 Scoring Water Quality ........................................................................................... 119 5.2.1 Nutrients ................................................................................................ 120 5.2.2 Chlorophyll ............................................................................................ 121 5.3 Water Quality Taura grades .................................................................................. 122 5.4 Water Quality Indicators considered but discarded or covered elsewhere ......... 123 5.5 Future Scoring ....................................................................................................... 124 6 Water Security ....................................................................................................... 125 6.1 Introduction .......................................................................................................... 125 6.2 Scoring Water Security ......................................................................................... 125 6.2.1 Water Abstraction and Use ................................................................... 125 6.2.2 Groundwater Allocation ........................................................................ 128 6.2.3 Rural Water Use .................................................................................... 129 6.2.4 Urban Water Use ................................................................................... 130 Scoring RCU for Urban Water Use ........................................................................ 132 6.2.5 Water Human Health and Safety .......................................................... 132 6.3 Water Security Taura Grade ................................................................................. 134 6.4 Water Security Indicators Considered but Discarded ........................................... 135 6.5 Future Scoring ....................................................................................................... 136 2015 Pilot Waikato River Report Card: Methods and Technical Summary 7 Effort ..................................................................................................................... 138 7.1 Introduction .......................................................................................................... 138 7.2 Scoring Effort ........................................................................................................ 139 7.2.1 Major Point Discharges ......................................................................... 139 7.2.2 Dairy Shed Consents .............................................................................. 139 7.2.3 Soil Conservation and Farm Plans ........................................................