Fonterra is spending $20 million to clean up five major waterways in dairying regions throughout New Zealand.
Working alongside the Department of Conservation, Fonterra will spend $2 million each year over the next decade to improve water life.
The areas are: Kaipara Harbour in Northland, the Firth of Thames and the Areare, Ruatuna and Rotomanuka peat lakes in Waikato, Lake Ellesmere in Canterbury and Waituna lagoon in Southland.
The dairy cooperative will work with farmers, iwi and communities planting trees and managing pests and weeds.
Fonterra said on Thursday the dairy industry still has work to do and hoped the waterways can be examples of dairy farms and the natural environment working together.
The areas were picked as significant waterways next to major dairying areas.
Conservation Minister Nick Smith welcomed investment by Fonterra, saying it is the biggest corporate contribution to conservation to date and hoped other major industries would get on board.
But the Green Party said cuts to the Department of Conservation's budget has forced it to rely on corporate hand-outs to clean up waterways - and it shouldn't have to beg for money.
Conservation spokesperson Eugenie Sage said the Government has cut DoC's funding by $54 million and more money would avoid it being forced into projects that corporates want.