Bay of Plenty Regional Council is asking anyone who notices oil near Matapihi to report it to their pollution hotline.
The council received calls of an oil spill at Matapihi in Tauranga Harbour south of the rail bridge, at about 4pm.
The oil, which appears to be black oil, currently affects an area of shoreline of less than 50 metres and there is a light sheen on the water, says Bay of Plenty Regional Council compliance manager - urban, regulatory and response Stephen Mellor.
Stephen says staff were out over night attempting to clear as much of this oily debris as possible before it got dark.
"Staff be back out at first light assessing the scene and finishing any clean-up which was not possible last night."
If anyone notices any further areas of oil, people are encouraged to call the Regional Council’s Pollution Hotline on 0800 884 883 to report it."