| 10 Jan 2023


Health Warning – Algal Bloom in Saltwater Creek (Timaru) near the SH1 bridge (Ōtipua)

Te Mana Ora | Community and Public Health has issued a health warning for Saltwater Creek, (Ōtipua), Timaru near the State Highway 1 bridge. The warning follows potentially toxic algae (planktonic cyanobacteria) scums observed in the Saltwater Creek (Ōtipua), Timaru near the State Highway 1 bridge. People should avoid the area and animals, particularly dogs, should not be allowed near the water until the health warning has been lifted.

There are also other access points along the Saltwater Creek (Ōtipua), Timaru near the State Highway 1 bridge that may have planktonic cyanobacteria present.

Dr Cheryl Brunton, Medical Officer of Health for Te Mana Ora, National Public Health Service Te Whatu Ora, says the algae can appear as a thick surface scum, sheens or can be present as green globules floating in the water column and can produce toxins harmful to people and animals.

“People should avoid contact with the water until further notice.”

“Exposure may cause skin rashes, nausea, stomach cramps, tingling and numbness around the mouth and fingertips. If you experience any of these symptoms visit your doctor immediately and please let your doctor know if you have had contact with the river water”, Dr Brunton says.

Pets that show signs of illness after coming into contact with potentially toxic algae should be taken to a vet immediately.

People and animals should remain out of the waterways until the warnings have been lifted.

Fish and shellfish can concentrate toxins and their consumption should be avoided. If fish are eaten, remove the gut and liver and wash in clean water.

Further information on gathering Mahinga Kai can be obtained below.

“People are advised to avoid contact with the downstream water bodies,” says Dr Brunton.

Environment Canterbury is monitoring the sites and the public will be advised of any changes in water quality.

Facts about cyanobacteria

  • Cyanobacteria occur naturally but can increase rapidly during warmer months.
  • Algal blooms are caused by a combination of nutrients in the water (such as nitrogen and phosphorus), and favourable weather conditions (e.g. increased temperature, calm days).
  • If the water is cloudy, discoloured, or has small globules suspended in it, avoid all contact.
  • Not all cyanobacterial blooms are visible to the naked eye and toxins can persist after the blooms disappear.
  • Cyanobacterial concentrations can change quickly with changing environmental conditions (e.g. wind). If a health warning is in place avoid contact with the water.
  • If a health warning is in place avoid contact with the water.
  • Although district or city councils may place warning signs, these may not be seen at the numerous river access points, hence the need for people/ dog-walkers to treat every low-flowing river cautiously.

For further details visit: https://www.lawa.org.nz/explore-data/canterbury-region/

Or contact Te Mana Ora on (03) 364 1777:


For more information about Mahinga Kai:


For further information, contact:

Karen Berry
Communications Manager
Te Whatu Ora South Canterbury  
021 139 7442