New Zealand’s coastal waters are widely used for a range of recreational activities, such as bathing, sailing, boating, various forms of surfing, water skiing, underwater diving and shellfish gathering. Maintaining and protecting the quality of this recreational water is therefore an important environmental health and resource management issue.
In the past, guidelines for assessing the public health risk of using recreational waters have been largely based on microbiological faecal indicator counts. The previous (1999) marine bathing guidelines (Recreational Water Quality Guidelines) were developed using the results of international and New Zealand studies, and after consultation with regional and local environmental and health agencies.
The guidelines presented here move away from the sole use of guideline values of faecal indicator bacteria, and instead use a combination of a qualitative risk grading of the catchment, supported by the direct measurement of appropriate faecal indicators to assess the suitability of a site for recreation. In addition, alert and action guideline levels are used for surveillance throughout the bathing season.
The two components to providing a grading for an individual beach are:
- the Sanitary Inspection Category (SIC), which generates a measure of the susceptibility of a water body to faecal contamination
- historical microbiological results, which generate a Microbiological Assessment Category (MAC), which provides a measurement of the actual water quality over time.
These two combined give an overall Suitability for Recreation Grade (SFRG), which describes the general condition of a site at any given time, based on both risk and indicator bacteria counts. This grade helps to determine whether ongoing monitoring is required, and provides the basis for telling people whether or not the water is suitable for recreational use, from a public health perspective.
Throughout this document the term ‘beach’ refers to both marine and freshwater recreational water sites.
The aim of these guidelines is to help water managers control the public health risk from microbiological contamination in recreational waters, and to provide for monitoring and reporting on the general health of beaches. The guidelines were designed to provide guidance to water managers in implementing the Resource Management Act 1991 (RMA), and the Health Act 1956 for shellfish – gathering or contact recreation. A crucial part of this is ensuring that the public are informed of the health risks in time for them to make informed decisions about whether to enter the water. The guidelines replace the previous Ministry for the Environment / Ministry of Health Recreational Water Quality Guidelines published in November 1999.
Guidance is provided for three categories of water use:
- marine bathing and other contact recreation activities
- freshwater bathing and other contact recreation activities
- recreational shellfish gathering in marine waters (but not commercial shellfish harvesting).
The Ministry for the Environment is specifically concerned with ensuring that the public has ready access to regional or local authority water quality information on the potential health risks from faecal contamination of recreational waters. The guidelines should provide this.
The guidelines also provide the monitoring protocol for the state of the environment indicators “the percentage of monitored beaches in each beach grade”, and “the percentage of the season beaches or coastal areas were suitable for contact recreation or shellfish gathering”.
The guidelines have been developed over an extensive period of consultation with regional and local councils and health authorities, and present a preferred approach to monitoring recreational waters. They are not legislated standards that must be adhered to at all times.
The guidelines cover the monitoring and interpretation of results from surveys for bacteriological indicators of faecal contamination in recreational waters. They do not cover other impacts on the above water uses, such as water clarity, chemical pollution, or marine biotoxins from algal blooms. The guidelines should not be used as the basis for establishing conditions for discharge consents, although they may be used as a component for decision making.
Documents that may be of interest to anyone managing water for contact recreation include two produced by the Ministry for the Environment:
- Water Quality Guidelines No 1, which covers the management of biological growths in rivers used for swimming
- Water Quality Guidelines No 2, which covers the management of water clarity for bathing in freshwaters.
These guidelines take precedence over the ANZECC Water Quality Guidelines for Fresh and Marine Water for microbiological water quality.
Finally, visit the Ministry for the Environment’s website for further information on water-quality publications.
© Ministry for the Environment