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

• 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.