More than $4 million will be spent to make Lake Hayes swimmable again.
The Department of Conservation has announced a raft of new projects in the South Island funded through the Jobs for Nature programme.
One of them is the rehabilitation of Te Wai Whakaata, the Lake Hayes catchment.
Over the past 70 years, the 280ha lake near Queenstown has suffered from a build-up of nutrients from human activity.
This includes historical fertiliser application, septic tank effluent and the removal of wetlands and riparian plantings. The catchment has been used for agriculture since the late 1800s.