The Hawke's Bay Regional Council and Napier City Council are again warning about pollution after the discovery of what is regarded as a "small" discharge of diesel or oil into the Napier inner harbour on Monday.
The councils said the leak, via stormwater pipes, was a reminder to local industries to check their operations to try to avoid such problems.
A discharge of diesel/oil (hydrocarbons) was reported at the western end of the inner harbour, part of what is otherwise known as Te Whanganui a Orotu or the Ahuriri Estuary.
The small slick was noticed by Cam Hopkirk, an employee of Now Broadband in Ahuriri, who was walking past about 3.30pm on Monday.