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
Monitoring results from the 2017/18 summer period at freshwater sites show that of the 15 sites in the three territorial authorities, only six were rated as Fair or above and 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 three sites out of four rated Fair or above, with a further two sites left ungraded because of insufficient data (i.e. only 2 years of data when at least 3 years is required to grade a site).
No freshwater sites had improved since the previous year. One site on the Selwyn River was downgraded from Good to Fair.
Of the coastal sites, the eight Christchurch beaches were all graded Fair or above, while the Avon-Heathcote Estuary had three Poor sites and four Fair or Good. Lyttelton Harbour and Banks Peninsula each contained eight sites that were all rated Good or Very Good, apart from Diamond Harbour which contained a Fair grading. Waimakariri had five coastal sites, which were all graded Good or above except for the Ashley Estuary with a rating of Poor.
No coastal sites had improved since the previous year. Three sites were downgraded, Scarborough Beach and Diamond Harbour Beach from Good to Fair, and Paradise Beach from Very Good to Good.
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 exist.
All coastal beach, bay and harbour recreation sites have a suitability for recreation grade (SFRG) of ‘fair’ to ‘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, and the Ashley River/Rakahuri – Saltwater Creek Estuary.
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 source
Environment Canterbury’s annual report on Canterbury water quality monitoring for primary contact recreation.
Data access
Report available from Environment Canterbury in PDF format
Date updated
Latest report dated August 2018, produced annually
Territorial Authorities - Christchurch City Council, Waimakariri District Council, Selwyn District Council
Other variables
The individual sites and their ratings
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.
