Reports on social media alerted authorities to a Pandora industrial area spill in which thousands of litres of tallow and water flowed into Napier's Ahuriri Estuary.
Hawke's Bay Regional Council resource use manager Wayne Wright said it was the posting of images and comments on social media that alerted the staff about 1.30pm on Monday, not any calls to the council or pollution hotline 0800 108838.
"The discharge had been noticed several hours earlier by members of the public with photographs and comments posted on social media, however the regional council was not contacted directly," Mr Wright said yesterday.
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He said staff would attend immediately when incidents were reported, and added: "It is better to be safe than sorry and there's no such thing as a bad call.
"We would rather be told and have us make an assessment rather than not have it reported."
By the time the council was made aware of the spill from bulk storage operation Liqueo in Humber St, staff from Lowe Corp and Classic Sheepskins had already taken steps to close the Tyne St drain pollution prevention gates to minimise and stem the flow of tallow from the drain into the estuary, to minimise the impact on the environment.
Mr Wright said those staff and their companies "are to be applauded for taking decisive action to minimise the harm this spill may have caused."
"This is a positive indication of the commitment people have to protect our environment, and so pleasing that the people concerned were prepared to take time away from their own business operations to help regional and Napier City Council staff," he said.
Investigation is continuing into the cause of the spill and it appears it may have resulted from a faulty connection between the trade-waste and stormwater connections at the tallow plant.
Both HBRC and Napier City Council are working to confirm the cause and take appropriate action to prevent such a situation happening again.
Earlier this year, meat processor Fresh Meats NZ, of Mersey St, Pandora, admitted unlawfully discharging waste into a stormwater system and contaminating the estuary in September last year, while in January 2015 tallow escaped into the estuary after about 13 tonnes spilled into drains in the area when a valve on a truck ruptured.