A first of its kind study is casting concerns about the quality of our waterways.

Land, Air, Water Aotearoa has been monitoring waterways over the past decade, and the analysis shows two out of five sites were "likely or very likely, degrading".

This means the ability for our rivers and streams to support the lives of snails and insects is becoming more challenging, which plays a vital role in the health of our waterways.

Lake and freshwater science professor at Waikato University Troy Baisden told Larry Williams says the new and most concerning data is that the smaller organism that fish eat are eating.

“The question that now becomes is what we do with that. What does it tell us what we should do?”

Baisden says the report doesn’t make clear how New Zealanders can do more to help fix the rivers.

He says there are some upsides, as the quality is improving in some parts of the country.

LISTEN TO TROY BAISDEN TALK WITH LARRY WILLIAMS ABOVE