Waimakariri River in Canterbury. Photo: 123rf.com
People are being told to avoid popular swimming spots along the Waimakariri River in Canterbury due to high levels of faecal bacteria.
Health New Zealand issued a health warning about unsafe recreational water quality upstream of the Old Highway Bridge North Bank.
National Public Health Service medical officer Dr Cheryl Brunton said rainfall in the area in the last few days had most likely caused the high levels of faecal bacteria.
Water contaminated by human or animal faecal matter could contain a range of disease-causing micro-organisms such as viruses, bacteria and protozoa, she said.
"In most cases the ill-health effects from exposure to contaminated water are minor and short-lived. However, there is the potential for more serious diseases, such as Hepatitis A or Salmonella infection."
Brunton said a number of other popular swimming sites in Canterbury might also have high levels of contamination after the recent rainfall.
"People should avoid all rivers and beaches for at least two days after heavy rain," she said.
"Water quality at affected sites is not considered suitable for recreational uses including swimming because of the risk to health from the bacteria and other pathogens."
Eating shellfish from these sites should also be avoided.
People can check out where it is safe to swim on Land Air Water Aotearoa's website.