Waitara's sewerage system has failed for the second time in a week.
A power failure to the pump station system controls for the northern Taranaki town caused sewage to overflow from the marine outfall overnight.
The sewage was discharged 1.25km out to sea. None went into Waitara River.
Council staff said they did not yet know the cause of the latest failure.
On Saturday, the multimillion-dollar sewer pipeline between Waitara and New Plymouth sprung a leak because of a blown gasket, and people were warned to stay out of Waiongana Stream.
Signs warning against swimming and collecting shellfish for 20 days were put up on Waitara Beach.