Rivers

Our rivers are famous – because they’re fast. We are the white-water capital of the world. The reason our rivers are so fast is because our mountains are so big.

Our white-water duck. Photo: A Reith

Rain and snow feed the little streams high on the mountains. The little streams join to make bigger streams. And the bigger streams join to become a wild river.

The snow-melt and rainwater travels through narrow gorges, and this creates white water. Rafters love them, so do filmmakers, daredevils, fishers, tubers and swimmers!

These rivers carry a precious cargo – such as our endangered duck (whio), dotterel and longfin eels.

These creatures call these rivers home, however many find that their rivers are being turned into hydro-dams, or toilets.

Not a cow toilet!

Once upon a time all of our rivers were lined with forests. This helped to keep our rivers healthy. The forests would shade our rivers, and stop soil washing into them.

Now, many of our rivers are surrounded by farmland and cows. The trees by the rivers were chopped down to make paddocks which means our river water is warmed by the sun. Sometimes cows walk into the rivers and use them as their toilet!

The warm water isn’t good for our native fish and stream insects because it is too hot for them to survive. The rivers also become polluted with bacteria from cow poo and nitrogen from cow wee.

To help clean up our rivers some farmers plant trees by the rivers on their farms to make the water shady and cool again. Plus the tree roots help to filter out any fertiliser that might wash into the river. They are also putting up fences to stop the cows getting into our rivers

Sometimes this isn’t enough though because there are hundreds of cows living nearby and their wees seeps into ground, and then into our rivers.

This makes weeds and bacteria grow, they use up the oxygen in the water choking the other stream animals.

Not another hydro-dam!
 

Damming a river is one way to make electricity. Many people think it is one of the best ways to make electricity because it is clean, and green.

• It does not release co2 into the air ,like our coal burning power stations, so it doesn’t cause air pollution, or climate change.
• It doesn’t waste water.

But wait, these rivers are the homes of our native creatures. Dams change our rivers forever. They flood the valleys, killing the surrounding forest and some of the creatures that live there. Without the forest to live in birds and other creatures become homeless

A place to call home

Our young longfin eels (called elvers) make a long journey from Tonga back to their home river in New Zealand. Some find their passage is stopped by hydro-dams.

They are so determined to go home that these finger-sized elvers will try to climb these hydro-dams. Millions of them die because they get caught in the pumps and turbines. Some also get baked in the hot sun while they go up the dam.

On the Rangitikei river however, eel-fanatic Bill Kerrison helps them on their way.