Northland Health is warning the public not to swim in Whangarei Harbour or collect shellfish until further notice due to a big sewage spill.
Raw sewage poured into the harbour on Thursday after repairs to a pipe were delayed overnight.
Contractors fixing a pipe on Wednesday found a joint they expected to be bolted on had instead been welded in place.
Whangarei District Council says the contractor called in sucker trucks when they realised the repairs would not be finished in time to handle peak sewage flows on Thursday morning.
The council says about 6,000 cubic metres of sewage went straight into the harbour between 6am and 1pm on Thursday, when repairs were completed.
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