Warnings and Alerts

Active warnings and alerts for Canterbury region

• Rahui - Toxic algal bloom

  14 MAR 2026 By ENVIRONMENT CANTERBURY (MB)

  Te Rūnaka o Ngāti Wheke advises that, due to the presence of a toxin producing algal bloom currently affecting the Koukourarata / Port Levy Harbour, and the associated risk to public health, a rāhui has been placed on the taking of shellfish from Sumner Beach, Scarborough Beach, Taylors Mistake and...
• Health Warning - Toxin-producing algal bloom

  13 MAR 2026 By ENVIRONMENT CANTERBURY (MB)

  14 March 2025 Health Warning - Toxin-producing algal bloom in Port Levy | Koukourarata  Health New Zealand | Te Whatu Ora has issued a health warning after extremely high levels of paralytic shellfish toxins were found in routine samples taken from ...
• Advisory Note - Shellfish biotoxin warning

  13 MAR 2026 By ENVIRONMENT CANTERBURY (MB)

  13 March 2026 Advisory Note - Shellfish biotoxin warning New Zealand Food Safety (NZFS) has issued a public health warning advising the public not to collect or consume shellfish gathered from the northern side of Banks Peninsula. The warning extends from New Brighton to the northern side of Hickory...
• Advisory Note: Unsafe Recreational Water Quality Oil Spill

  8 MAR 2026 By ENVIRONMENT CANTERBURY (MB)

  Updated 13 March 2026 Advisory Note - Unsafe Recreational Water Quality at Duvauchelle Bay Due to an oil spill, water quality at Duvauchelle Bay is considered unsuitable for swimming, other water-based activities and shellfish gathering.
• Health Warning – Unsafe Water Quality (1)

  6 MAR 2026 By ENVIRONMENT CANTERBURY (KD)

  Media Release 6 March 2026 Health Warning – Unsafe Recreational Water Quality at Ashley River | Rakahuri at SH1  Health New Zealand | Te Whatu Ora has issued a health warning after high levels of faecal bacteria were found in Ashley River | Rak...
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  Toxic algae warnings for cyanobacteria in rivers

  23 FEB 2026 By ENVIRONMENT CANTERBURY (KD)

  HEALTH WARNING UPDATE ISSUED BY THE NATIONAL PUBLIC HEALTH SERVICE The National Public Health Service have issued a health warnings for toxic algae. The warnings follow detection of moderate to high cover of toxic algae (benthic cyanobacteria) in the:  Waihao River at Gum Tree Flat Rd (Don'...
• Lake Benmore weed control notice

  18 FEB 2026

  Toitū Te Whenua LINZ is undertaking lakeweed control work on Lake Benmore to target Lagarosiphon major. The herbicide diquat is used to control weed. As per the label recommendation, the public are advised to stay out of the treatment areas and refrain from taking water from the lake for any pu...
• Lake Hood - Public health warning for potentially toxic algae (cyanobacteria)

  14 JAN 2026 By ENVIRONMENT CANTERBURY (KD)

  Health Warning – Harmful Algal Bloom in Lake Hood  Health New Zealand | Te Whatu Ora has issued a health warning after potentially toxic harmful blue-green algae (planktonic cyanobacteria) were found in Lake Hood.   People should avoid the Lake and animals, pa...
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  Lake Pegasus cyanobacteria warning

  10 DEC 2025 By ENVIRONMENT CANTERBURY (SK)

  Issued 10 December 2025: Health Warning – Algal Bloom in Lake Pegasus The National Public Health Service has issued a health warning after potentially toxic harmful blue-green algae (planktonic cyanobacteria) was found in Lake Pegasus   People should avoid the Lake and animals, particu...
• Lake Rotorua - permanent cyanobacteria health warning

  6 MAR 2023

  Long term water testing indicates that there is a regular bloom of the potentially toxic cyanobacteria Anabaena and/or Microcystis present. There is a permanent health warning advising people to avoid contact with water at this lake. Environment Canterbury continues to monitor the lake on a regular...
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  St Annes Lagoon/Mata Kopae cyanobacteria warning

  7 JUL 2022 By ENVIRONMENT CANTERBURY

  Permanent Health Warning for Algal Bloom at Mata Kopae/St Anne’s Lagoon. Issued: 7 July 2022 Long term water testing indicates that potentially toxic cyanobacteria bloom periodically in Mata Kopae/St Anne’s Lagoon. There is a permanent health warning advising people (and animals) to avoid contact wi...