Why waterway preservation is important to us as New Zealanders is for a multitude of reasons. While compared on an international level, New Zealand could be considered generally good, however, according to the National Rivers Water Quality Network (NRWQN) our water quality is on a decline. Trends in NRWQN data between 1989 and 2007 show an overall decline in water quality across the monitoring network. In particular, there is a significant increasing trend in nitrogen (as nitrate and nitrite), dissolved reactive phosphorus and total phosphorus levels.
Pollutants are already putting a strain on our freshwater ecosystems. Pest fish and weeds are also a problem. To feed, fish such as koi carp sift through bottom sediments, making the water dirty and unsuitable for swimming. Others, such as catfish, prey on native species like kura. Oxygen weeds suffocate boats and swimmers in the ocean. What can you do to help halt the spread of pests in freshwater? Thoroughly inspect and clean your boat, boat trailer and gear before moving between waterways.