Skip to main content.

Water quality at freshwater swimming spots

New Zealand’s coastal beaches, rivers and lakes are widely used for a range of recreational activities such as swimming, sailing, surfing, water skiing and underwater diving. Maintaining and protecting recreational water quality is therefore an important public health and resource management issue.

Latest freshwater quality compliance with E. coli guidelines

Regional and district councils in New Zealand monitor water quality for contact recreation at about 200 sites on rivers and lakes every summer (and about 350 coastal sites).

Water samples are typically taken once a week over the summer and tested for the concentration of Escherichia coli (E. coli) bacteria. E. coli bacteria, while generally not harmful themselves, indicate the presence of faecal material and disease-causing micro-organisms in fresh water.

The E. coli results are compared to the ‘action’ threshold of 550 E. coli per 100 millilitres of water from the Microbiological Water Quality Guidelines for Marine and Freshwater Recreational Areas (also known as the 'guidelines for contact recreation').

Did you know?

  • Recreational water quality can be affected by effluent run-off from farmland, human wastewater discharges and stormwater outfalls. Bacteria levels are often highest after rainfall.
  • Water that has been contaminated with human or animal effluent can carry a variety of disease-causing organisms.
  • Disease-causing organisms can pose health risks to people using the water for activities such as swimming. Very young children, the elderly or people with impaired immune systems are particularly vulnerable.

Information on the limitations of the water quality at freshwater swimming spots indicator.

The above information has come from the snapshot report on recreational water quality and Environment New Zealand 2007.

Return to the main freshwater page.

Last updated: 29 June 2009