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New Zealand Guidelines for Cyanobacteria in Recreational Fresh Waters:
Interim Guidelines

These guidelines provide advice on how public health risk associated with cyanobacteria in recreational waters can be managed. They have been developed in response to:

  • help councils and health agencies develop monitoring protocols appropriate for local conditions and circumstances
  • encourage the adoption of a nationally unified approach to managing cyanobacterial risk in water used for recreational purposes.

The guidelines set out a monitoring framework for lakes (mainly planktonic cyanobacteria) and rivers (mainly benthic cyanobacteria).

These guidelines are a companion to the Microbiological Water Quality Guidelines for Marine and Freshwater Recreational Areas.

Status and use of the Guidelines

These guidelines are interim.  This version has been released for trial use by monitoring and health agencies until the end of the 2011/12 summer, at which point it will be revised, based on feedback from practitioners.  The guidelines will subsequently be released as a final version.

Feedback on any aspect of guideline implementation is welcomed.  Please send comments to Environmental.Reporting@mfe.govt.nz

The guidelines are not mandatory. They provide a recommended approach that is considered best practice for many management circumstances, given current understanding of cyanobacterial risks in New Zealand fresh waters. Local decisions about whether to follow the guidelines’ approach should ultimately result from consideration of site-specific factors (such as resource availability, historical understanding of local algal bloom conditions), as well as the guidance offered in this document.

Acknowledgements

Prepared for the Ministry for the Environment and the Ministry of Health by:

Susanna A Wood: Cawthron Institute
David P Hamilton, Wendy J Paul: University of Waikato
Karl A Safi: National Institute of Water and Atmospheric Research
Wendy M Williamson: Environmental Science and Research Ltd

These authors make the following acknowledgements:
We thank members of the 2008 Cyanobacterial Working Group for their valuable suggestions during the preparation of these guidelines. Members were: Michael Taylor (Ministry of Health), Matthew Bloxham (Environment Bay of Plenty), Phil Shoemack (Bay of Plenty District Health Board), Karen Thompson (National Institute of Water and Atmospheric Research), Graham Sevicke-Jones and Anna Madarasz-Smith (Hawke’s Bay Regional Council), Joanne Lynch (Hawke’s Bay District Health Board), Juliet Milne (Greater Wellington Regional Council), Annette Nesdale and Scott Rostron (Hutt Valley District Health Board), Shirley Hayward (Environment Canterbury) and Rachel Ozanne (Otago Regional Council). We thank Laura Watts (Greater Wellington Regional Council) and Mark Heath (Victoria University) for the use of their data on benthic cyanobacteria in the Wellington region. We are indebted to Cathy Kilroy (National Institute of Water and Atmospheric Research) for her advice and assistance during the development of benthic cyanobacterial sections. Mike Thompson (Ministry for the Environment) is thanked for his guidance throughout this project.

The Australian National Health and Medical Research Council is thanked for permission to include modified sections of their recreational guidelines (NHMRC, 2008) in this document.

Professor Daniel Dietrich (University of Konstanz) and Keith Hamill (OPUS International Consultants) are thanked for their thorough and constructive reviews.

How to use this document

This document is divided into four main sections, plus 14 appendices.

Section 1. Introduction provides an overview of the purpose and status of the document as well as advice on who should use it.

Section 2. Framework provides a background to the overall guidelines approach, recommendations on agency roles and responsibilities, and information on the condition of use of this document.

Section 3. Guidelines describes the recommended three-tier monitoring and action sequence for planktonic and benthic cyanobacteria.

Section 4. Sampling provides advice on sampling planktonic and benthic cyanobacteria.

The appendices give further background information and include templates for data collection and reporting, including:

  • background information on known cyanotoxins and their distribution in New Zealand
  • information on the derivation of guideline values
  • photographs of typical bloom events
  • a list of biovolumes for common New Zealand cyanobacteria
  • templates for field assessments
  • suggested media releases and warning sign templates.

A glossary provides definitions for abbreviations and terms used in these guidelines.

Further information

  • See the fresh water page for other guidelines, tools, reports, policies, projects and partnerships related to fresh water.
  • For a full list publications relating to water refer to the water publications page.