Nelson City Council are investigating an oil spill that has affected the city's marina.
Believed to have come from a vessel's bilge between 7pm and 2am on Sunday night, the spill was cleaned up by the council's environmental response team, with between two and three tonnes of vegetation removed from the foreshore.
"Due to the large amount of pollutant, we believe this spill has come from a larger vessel," says Clare Barton, Group Manager Environmental Management.
"We were lucky that the northerly wind direction blew the oil into the marina where it could be more easily removed, if the wind had been blowing the other direction and had it been swept along the Boulder Bank there could have been serious impacts for our wildlife.
Costs of clean-up are estimated to be considerable, with material needed to be trucked from Christchurch for appropriate disposal.