The lake of buttermilk at Atiamuri in Waikato has been drained and the product spread out over farmland, but the regional council's investigation into whether it was legal continues.
Fonterra has been unable to cope with milk volumes in the North Island and has been dumping low value milk by-products.
The butter milk, a by-product of butter making, had been trucked to an Atiamuri farm from Fonterra's processing plants in Waikato and Bay of Plenty.
Waikato Regional Council's compliance division manager, Rob Dragten, says the lake's gone now, but the council's investigation is ongoing.
He says it could be a good time for councils and dairy companies around the country to reassess their contingency plans in the light of the high volumes of milk currently being produced.
Mr Dragten says the Waikato Regional Council has just granted consent to Fonterra for it to dispose of surplus milk products at another site in the region.
