Looking after a river you use

Everyone who uses a river changes it a little: boots on the bed, a boat in the water, a tent on the terrace, a fire on the gravel. One visit makes little difference. Thousands of visits, spread over years, add up. The good news is that the habits that protect a river are simple, and most of them cost nothing.

Check, Clean, Dry

The most important habit is the one that stops freshwater pests moving between rivers. DOC explains in its guidance for whitebaiters that moving wet gear between waterways can spread pests such as didymo, invasive freshwater clams and weeds, which can reduce water quality, clog nets and choke waterways. The same applies to boots, waders, kayaks, packrafts, fishing gear, swimming gear and anything else that has been in the water.

The methods are updated as new pests turn up, so it is worth checking the current advice before each season rather than relying on memory. Whitewater NZ’s Check, Clean, Dry page explains one recent reason: the invasive gold clam was found in the Waikato River in 2023 and has since spread along it. Gold clam is an Unwanted Organism under the Biosecurity Act, there is a Controlled Area on part of the Waikato, and there is a specific, updated cleaning method for the North Island. If your gear has been in affected water, the rules on moving it are strict.

A few practical points:

• Felt-soled boots and anything absorbent hold water for a long time and are hard to clean properly. Many river users now avoid them.
• Drying means completely dry, inside and out, including the folds of an inflatable boat and the inside of boots.
• If you can’t clean or dry it, use that gear on one river only.

Toileting near water

Human waste near rivers is a health problem for everyone downstream and an unpleasant one for the next visitor. Use the hut or campsite toilet wherever there is one. Where there isn’t:

• go well away from water, tracks and campsites
• dig a small hole and cover it afterwards
• pack out toilet paper and anything sanitary
• never use the riverbed, gravel bars or flood channels, which the next flood will wash straight into the water

DOC’s care codes for visitors go into more detail, and many popular areas have their own rules.

Campsites and fires

River terraces make lovely campsites, which is why the good ones get worn out. Use established sites where they exist rather than clearing new ones. Wash dishes and yourself away from the water, and tip waste water onto the ground, not into the river. Soap, even the “biodegradable” kind, doesn’t belong in a stream.

Check fire rules before you go; many areas restrict or ban open fires, and the rules change with the season. Where fires are allowed, keep them small and use an existing fireplace.

Take all rubbish and food scraps out. Food waste attracts rats, stoats and other predators that prey on birds like whio, which nest along the same rivers. Our note on whio explains why that matters.

Weeds on the banks

Many river margins in New Zealand are lined with introduced plants, especially willows and gorse. Some willows were planted deliberately to hold banks, and they can still do that job. But weedy willows spread along rivers easily from broken stems, form dense stands that crowd out native plants, and can block channels. Gorse and other weeds take over gravel and banks in similar ways.

For most river users, the practical steps are small:

• don’t carry plant material between rivers; that is part of Check, Clean, Dry
• clean seeds off clothing, boots and dogs before you leave
• if you have land beside a river, talk to your regional council about what to plant and what to remove, and how

Riverside planting with natives, and fencing stock out of streams, are among the most effective things landowners can do for a river.

Helping keep track of river health

Regional councils monitor water quality at sites across the country, and you can look at their results on LAWA’s river quality pages, which show the state and trend of rivers in each region. It is a good way to learn about a river before you swim or paddle in it, and to see whether things are getting better or worse.

Many communities also run their own monitoring. Catchment groups, schools and clubs survey stream insects, water clarity and fish, and count birds. If you use a river often, joining one of these efforts is one of the best ways to give something back. Ask your regional council or local catchment group what is happening near you.

Before you swim

Water quality can drop sharply after heavy rain, when run-off carries contaminants from land into rivers. Check the latest swimming-spot information before you swim, especially after rain, and stay out of water that looks discoloured or smells bad. If you get sick after swimming, tell your doctor where you were.

The short version

• Check, Clean, Dry every time you move between waterways.
• Toilet well away from water, and pack out what you can’t bury.
• Camp on established sites; keep soap and waste out of the river.
• Take all food and rubbish home.
• Don’t spread weeds, and support native planting where you can.
• Learn your river’s health, and help monitor it if you can.

A river looked after by its users stays worth visiting. Most of the work is simply not leaving a mark.