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How to Stay Safe around Rivers

More people drown in rivers than in any other aquatic environment in New Zealand.

We have 180,000 kilometres of rivers in New Zealand.

Rivers change

Rivers are changeable and unpredictable and can contain hidden dangers.

Look before you leap. Check for hidden objects and swimming holes can change depth summer to summer and currents can move objects underwater.

Near dams water levels and flows can change significantly throughout the day and massive flows may be released at any time.

River banks can become unstable during flood and after heavy rain. Stay well clear of a river in flood.

Rivers are powerful

There are strong currents and suction effects, and deep water especially near dams.

If you’re wading, a wading staff will give extra support and you can feel ahead for obstructions or changes in flow. Have someone with you for extra support and safety

Rivers are not patrolled. Never enter a river alone. If in doubt stay out.

The pressure of moving water is constant and can be powerful even if the river looks slow moving and calm.

Rivers can be unpredictable

Check weather forecasts including rainfall in the hills above that could fill the streams and rivers where you are. Watch out for signage and do what it tells you to do.

Always enter feet first and establish an exit point before you enter. Check for hazards such as rapids downstream.

Heavy rain can cause river levels to change dramatically. Never cross a river in flood.

Swimmers often underestimate the power of a river and overestimate their abilities.

Swimming in Rivers

Swimming spots in rivers can be great places in summer. If you pick your spot carefully and check it out each time you swim there you can keep yourself and your friends safe.

Swimming in a river is different from swimming in a pool or in the sea. Swimmers often underestimate the power of the river or overestimate their own abilities.

The river bottom is irregular and can change from day to day. It is often difficult to tell how deep a certain part of the river is. Annually there are a number of serious injuries caused by people jumping into water that is too shallow.

Check out any jumping spot thoroughly before jumping. Do this by getting in the water and physically checking the depth and the whole landing area. Do this every time you visit a jumping spot to check that nothing has drifted into the landing zone since you were last there.

How to stay river safe:

  • Learn water safety skills, how to assess risk and how to swim.
  • Always swim as part of a group.
  • Check for hazards both where you are swimming and downstream.
  • Do not mix swimming with alcohol or drugs.
  • Read and obey any warning signage.

Safety and Hydrology

Water in rivers exerts a very powerful force against any fixed object. This force remains constant unlike the ocean where the force is released with each tidal surge.

The downstream flow of water is called laminar flow. Water flows in a straight line, changing direction at points of high resistance. The line of greatest depth and strongest laminar flow will be on the outside of the corners. The water on the inside of the bend is slower moving. 

Within New Zealand there is a recognised grading system for rivers. This classification is based upon difficulty, loss of height, amount and speed of water, and the number of hazards. Grade 1 is the easiest, Grade 6 is the hardest.

River Crossings

Most river crossings are conducted safely and successfully, however unfortunately not all crossings go so well. 

When attempting a river crossing, these three crucial decisions will help you to reduce the risk:

1. Should you cross?

Crossing alone is hazardous and it is not recommended that you get yourself into a river crossing situation if you are alone.

2. Where should you cross?

  • Never cross a river in flood – 80% of river crossing drownings have occurred when the river has been in flood.
  • Check the speed of the river, look downstream for run out hazards and see if there are good entry and exit points
  • Avoid crossing on a bend, above a place where another stream joins the river and where the water is dirty and cloudy.

3. How should you cross?

  • Check your clothing and equipment.
  • Avoid loose bulky clothes.
  • Wear your boots or shoes.
  • Try to keep the gear you are carrying in your pack/day pack dry. Make sure that it is all in plastic bags.

4. When crossing always:

  • keep your body side on to the current;
  • take small shuffling steps;
  • move diagonally downstream with the current to conserve your energy;
  • have a leader to control the crossing make sure that everyone can hear instructions before you get into the river;
  • have the strongest people at the upstream end to break the flow for the others;
  • have the upstream person just slightly ahead of the person next downstream and so on down the line. 

If the crossing does not go as planned:

Stay linked up and back up slowly out of the river. Do not break the link until everyone is into very shallow water.

Rivers in Flood

A significant danger is created when our rivers, creeks and streams flood. Debris and fast flowing currents can cause banks to become unstable and even a small rise in the water level can dramatically change the way a river flows.

When inland waterways are in flood it is important to keep out of the water wherever possible and keep well away from river and creek banks, they can become weak and subject to collapsing.

Fishing in Rivers

Do not enter the water if you are at all unsure. If in doubt, stay out! When wading rivers, take precautions and plan for the worst.

Wear a wading belt and a personal flotation device. Use caution when wading into deep water at river mouths, or making river or stream crossings.

Losing your footing when wading can be potentially hazardous and anglers can get into situations where injury or even death is a very real outcome.

All anglers should have a healthy respect for water and before heading out should tell someone where they intend to fish and how long they intend to be.

It is not always necessary to wade in order to fish successfully. If you are unsure about your wading ability, and you lack confidence in the water, don't wade!

Look for suitable pools to fish that can be reached from the riverbank or by using thigh waders to go into the water to knee-depth.

Linking arms with a fellow angler to cross a river will give you added stability, but you should proceed with caution.

For more on river fishing safety go to

Be River Safe 

How to Stay Safe around Rivers


River Water Safety Quick Facts

Rivers are changeable and unpredictable particularly after heavy rainfall.

Check for hazards

Upstream, downstream and where you’re swimming. Rivers contain hidden dangers such as submerged objects and snags.

Keep looking.

Can you see the bottom? Is it deep enough for jumping or diving? Does the riverbed drop away close to the edge? Could you handle the current if you got swept away?

Establish an exit point.

It’s easy to get in but can you get out?

Notes for Teachers

River Features
Crossing Rivers
Supervision at Rivers
Survival Swimming
Strainer Danger
The Force of Water
Swimming in a River
Planning a Trip
Peer Pressure
Watch Be River Safe Video

Fact Sheets

River Features
Crossing Rivers
Supervision at Rivers
Survival Swimming
Swimming in a River
Diving or Jumping in Rivers
Planning a Trip


River Features
Crossing Rivers
Survival Swimming
Strainer Danger
The Force of Water
Swimming in a River
Diving or Jumping in Rivers
Peer Pressure


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