A typical kiwi summer holiday consists of camping, barbecues and swimming in our lakes, rivers and seas. As a kid I remember spending hours jumping into waterholes and building dams in rocky rivers, and swimming out to pontoons in lakes. But our freshwater systems have become subject to pollution and degradation. A big pollutant to New Zealand’s waterways are fertilizer and faecal runoff from paddocks. However this can easily be managed by fencing waterways off from stock and planting a riparian zone between the waterway and paddocks. The plants in the riparian zone act as a filter, taking up the nutrients from runoff before it reaches the waterway. Also storm-water runoff in cities contains chemical pollutants.

Another threat to the quality of New Zealand waterways are aquatic weeds and algae. Didymo, also known as rock snot is a particularly notorious algae. Didymo forms large blankets that smothers everything, (rocks, native aquatic plants, fish, invertebrates) in the waterway. It is particularly nasty since it can spread easily and multiplies like crazy. Didymo is a single celled organism and so can simply be spread in one drop of water. Didymo can also cause huge problems as their large dense mats can clog drains and hydro-electro dams. This can lead to flooding and erosion. This algae and other fresh water weeds can have such a big impact on freshwater ecosystems as they can out compete native aquatic plants and reduce the habitat for native fish and invertebrates.

However we can all help in preventing the spread of didymo and other freshwater weeds and still enjoy our rivers and lakes on our holidays. Just remember the motto: check, clean, dry. Check everything that has been in contact with the water and remove any obvious clumps of plant matter. Clean everything that has been in contact with water with a solution of dishwashing detergent, salt or hot water that is at least 60°C. Then make sure everything dries completely, and ideally leave for 48hours before using again in a different waterway.

So get out and enjoy New Zealand’s waterways just as I did when I was a kid (and still do), and actively help protect them by simple three step Check, Clean, Dry, so our future generations can also know the enjoyment of a typical kiwi summer holiday.