The designers of a new online map hope it will aid farmers in their attempts to ease pressure on New Zealand's waterways.
The interactive map allows users to see how nitrogen levels have changed in recent years, as well as projections of what might happen in the future.
And while many waterways are badly polluted, the map does show that without efforts by farmers to mitigate runoff, the problem would be much worse.
Agresearch's chief Land and Water scientist, Professor Richard McDowell, spoke to Māni Dunlop.
