Rangitīkei District Council has been granted resource consent to divert part of the Rangitikei River away from the old Putorino landfill, which has been leaking rubbish into the water.
Residents raised the alarm with council late last year after finding rubbish in the river.
Chief executive Ross McNeil said the Rangitikei River had changed its course and subsequently eroded the bank on one side of the landfill site during a period of high flow.
The Putorino landfill was established under the former Rangitīkei County Council and is believed to date back to the 1970s.
At that time the river bank would have been well back from the edge of the landfill.