Whitebaiters in Christchurch are being warned against fishing in or around several popular waterways, on the eve of the whitebaiting season.
Canterbury Medical Officer of Health Alistair Humphrey says eating whitebait caught in Christchurch waterways is dangerous.
He advises whitebaiters to avoid the Avon River, Heathcote River or Avon-Heathcote Estuary this season.
Dr Humphrey said that before the earthquake, Christchurch's waterways were contaminated and rarely met recreational water standards.
Despite this, some people liked to collect whitebait from the Avon and Heathcote but ongoing repairs to wastewater infrastructure, means there is still the additional risk of contamination.