With the summer holiday season coming up, Waikato Regional Council and Biosecurity New Zealand are reminding everyone in
the Waikato region of the importance of cleaning their equipment between waterways to avoid the spread of unwanted
freshwater pests.
“Unwanted freshwater pests such as didymo, lake snow, and hornwort pose a serious threat to our rivers, streams and
lakes. Once in a waterway they can disperse rapidly and destroy the environmental, recreational and aesthetic values of
our waterways,” says Waikato Regional Council biosecurity officer Andrew McConnell.
“We are asking people moving between waterways to check, clean and dry any equipment that has come into contact with
river or lake water. Some freshwater pests, like didymo, are microscopic and can be spread by a single drop of water.
Even if you can’t see the danger you could be spreading it.”
Mr McConnell says before leaving a waterway, people should check items and leave any weed or debris they find at the
waterway.
All items should then be cleaned for at least one minute with a 5 per cent solution of biodegradable dishwashing
solution. That’s about one tablespoon of detergent per 250mL.
Water absorbent materials such as lifejackets, wetsuits and boots require longer soaking times to allow thorough
saturation.
Drying will kill didymo, but even slightly moist items can harbour didymo and other microscopic pests for months. To
ensure didymo cells are dead, the item must be completely dry to the touch, inside and out and then left dry for at
least another 48 hours before use.
Following these simple procedures will help slow freshwater pests like didymo from spreading throughout New Zealand
waterways.
“It’s everyone’s responsibility to try to preserve the environmental integrity of our waterways for future generations,”
says Mr McConnell.
“Just remember to Check, Clean and Dry when moving from one waterway to another, anywhere in New Zealand.”
For more information about didymo and freshwater pests go to mpi.govt.nz/check-clean-dry.