The quality of water for swimming is determined by measuring ‘faecal indicator bacteria’ which indicate the levels of disease-causing organisms in the water. Enterococci, measured in coastal waters, are types of faecal bacteria that naturally occur in the gut of humans and animals. Enterococci are the biological indicator for faecal contamination of coastal swimming sites.
In coastal waters, low counts of enterococci are acceptable, but too much faecal contamination can cause gastroenteritis or infections of the ear, eye, nasal cavity, skin, and the upper respiratory tract. Monitoring the levels of enterococci in the water helps us determine the immediate risk of swimming at monitored sites, as well as how suitable each site is for recreation in the long-term.
While many of Canterbury’s coastal bathing sites have reasonably good microbial water quality during periods of dry, stable weather, increased runoff from land after moderate to heavy rainfall events often increases faecal bacteria concentrations for short periods (up to 48 hours). When enterococci are detected above 280 per 100ml in two consecutive samples within 24 hours, swimming or other water-based recreational activities are not recommended. Exceedances trigger public health warnings and increase the frequency of sampling.
Regional councils are responsible for implementing a monitoring programme for recreational water quality (as outlined in the 2003 Microbiological Water Quality Guidelines for Marine and Freshwater Recreational Areas). This includes:
Reporting on monitored coastal sites graded suitable for contact recreation lets communities know where it’s safe to swim and undertake other water-based recreational activities. It also helps identify areas where further actions are needed to improve coastal water quality.
We collect water samples from over 40 popular coastal recreation sites (estuaries, beaches, and harbours) across the region between November and March in accordance with the 2003 Microbiological Water Quality Guidelines for Marine and Freshwater Recreational Areas, and the National Environment Monitoring Standard for coastal water quality sampling and data processing (NEMS, 2020).
After each summer sampling period, a water quality for contact recreation report is published. Each site is given a Suitability for Recreation Grade (SFRG) which describes the general condition of the site and any associated health risk. Sites graded suitable for recreational contact must have an SFRG of fair or better. The long-term grade is calculated from sample results from the last five seasons. Sites graded excellent, good, or fair have water quality suitable for swimming more often than the sites graded poor or very poor over the past five summers.
For more information on how the SFRG is determined, refer to the guidelines.
Canterbury’s Regional Coastal Environment Plan outlines areas that are classified as being managed for contact recreation and shellfish gathering. These areas have minimum standards of water quality (see Schedule 4) that must be met.
Our recreational water quality monitoring programme includes monitoring sites that are commonly used for swimming, boating, and paddling. Our monitoring helps ensure we know which popular bathing sites are safe for primary contact recreation activities, such as swimming, surfing, and diving.
We also work with territorial authorities to identify and mitigate contamination sources (i.e. leaky wastewater infrastructure).
Central government sets national policy through resource management laws and the New Zealand Coastal Policy Statement.
Resource users (e.g. industries, manufacturers and private consent holders) are required to adhere to the rules and standards set out in regional plans that address faecal bacteria contamination of coastal water.
National Public Health Service – Te Mana Ora is notified of high-risk monitoring results and issues public health warnings for unsuitable swimming sites. The responsibility for follow-up action to health warnings falls to the different agencies involved.
In Waitaha Canterbury, warnings are displayed for the public on the Land, Air, Water Aotearoa (LAWA) website and Can I Swim Here?, as well as the Environment Canterbury website.
Download the Water quality for contact recreation: Annual summary report 2023-24 season (PDF, 6.6MB)
See Can I Swim Here? on the LAWA website, as well as factsheets on faecal indicator bacteria and coastal and freshwater recreation monitoring.
View Ministry for the Environment/Manatū Mō Te Taiao and Statistics NZ/Taauranga Aotearoa publications that use our data for legislated national environmental reporting (i.e. 3-yearly Our marine environment reporting series and national environmental indicators).
Planning a trip to one of Canterbury's rivers, lakes or coastal areas? Find out where the public access points are and what you can expect when you get there. Our interactive recreational access map can help you explore our beautiful region and decide which publicly accessible site best suits your chosen activity. We have information available on more than 1,000 sites, stretching the entire length of the region.