Recreational water quality

Why is this important?

Communities want water in recreational areas (rivers, lakes and coastal areas) to be safe for swimming, fishing and other activities. Physical properties (e.g., temperature and clarity) and the concentration of different contaminants (chemicals, nutrients and bacteria) are often used to describe water quality in those areas. Determining whether water quality is “good” or “bad” generally involves comparing measured physical properties and contaminants with natural, or baseline conditions, conditions at reference waterbody sites, and with guidelines established to protect human health or ecological communities. 

Environment Canterbury’s recreational water quality programme monitors Canterbury’s key bathing and recreation sites for bacteria (E. coli in freshwaters and enterococci in marine waters), which indicate the presence of pathogens in water. Pathogens can cause illness in humans and animals. 

Key points

  • Records taken during the 2016/17 summer period at freshwater sites show that of the 15 sites in the three territorial authorities, only six were rated as Fair or above, suitable for primary contact recreation.
  • Christchurch has  four freshwater sites, only one of which was rated as Good. Selwyn has two sites out of five rated Fair or above.  Waimakariri has two sites out of three rated Fair or above, with a further two sites left ungraded because of insufficient data.
  • Of the coastal sites, the eight Christchurch beaches were all graded Good or above, the Avon-Heathcote Estuary had three Poor sites and four Fair or Good, while Lyttelton Harbour’s eight sites and Banks Peninsula’s eight were all rated Good or Very Good. Waimakariri had four coastal sites, which were all graded Good or above, and an estuary site with insufficient data to rate.

Note this is an interactive chart and you can click on the legend items to change what is shown on the graph.

Commentary

Most of the freshwater sites that are not recommended for primary contact recreation are found in the lower reaches of river catchments where  urban or agricultural land use intensity is high, and in some cases large bird populations or unrestricted stock access.

All coastal beach, bay and harbour recreation sites have a suitability for recreation grade (SFRG) of ‘good’ or ‘very good’. The only coastal sites that are considered unsuitable for swimming are in the Avon-Heathcote Estuary, which has a heavily developed urban catchment.

Commentary adapted with permission from Environment Canterbury’s annual Recreational Water Quality Report.

For information on individual sites, download our data tables or look at the original Environment Canterbury report.

Data notes

Sites graded very good, good and fair are considered suitable for contact recreation; however good and fair sites may not be suitable at times - for example, after heavy rainfall. Sites graded poor and very poor are generally considered unsuitable for contact recreation; there is typically notification of this via signage at the site and through the media.

Difference between LAWA and Environment Canterbury reporting

Prior to the beginning of the 2014/15 contact recreation season, the Land, Air, Water, Aotearoa (LAWA) website was launched to report the state of New Zealand’s environment. LAWA includes a recreational water quality component to its reporting, which details faecal indicator bacteria monitoring results collected each week by Environment Canterbury and other regional councils. Each bathing site has an overall risk classification for recreation. These are very low risk, low risk, moderate risk, and high risk/caution. Risk classes for each freshwater site are calculated using 95th percentile E. coli and enterococci values obtained over the last three years of monitoring (i.e. 2014/15 – 2016/17).

The method for calculating risk classifications on LAWA differs from that used by Environment Canterbury to calculate MACs and SFRGs. This is because Environment Canterbury follows the MfE & MoH (2003) guidelines, which stipulate using five years of microbiological monitoring data instead of three. Furthermore, LAWA risk categories do not take into consideration the influence of rainfall-affected data. Numerous sites are therefore considered as high risk on LAWA, when they may in fact be suitable for primary contact recreation under base flow conditions. In Canterbury, SFRG calculations are often adjusted for sites where high rainfall and flows are associated with elevated E. coli concentrations.

Source: Environment Canterbury Recreational Water Quality report, p30.

Data information and downloads

Data downloads available

Geographic  Area

Territorial Authorities - Christchurch City Council, Waimakariri District Council, Selwyn District Council

Other variables

The individual sites and their ratings

 

Information about the dataset

Data Source

Environment Canterbury’s annual Recreational Water Quality Report(external link).

Data Access

Report available online in PDF format

Date updated

Latest report dated November 2017, produced annually

Data Table Download

Download tables here [XLS, 36 KB]

Links to other information and reports

Additional Canterbury recreational water quality data can be found on the LAWA site(external link) – see data notes above about the differences in how LAWA and Environment Canterbury report the data.