Natural water cycle

The natural water cycle is the continuous movement of water around the world through the processes of evaporation, transpiration, condensation, precipitation, run-off, infiltration and percolation.

Natural water cycle process


What happens in the natural water cycle?

The natural water cycle uses physical processes to move water from the surface of the Earth to the atmosphere and back again.

  • Evaporation is when the sun shines on water and heats it, turning it into gas called water vapour which rises into the air.
  • Transpiration is when the sun warms people, plants and animals and they release water vapour into the air.
  • Condensation is when the water vapour in the air cools and turns back into a liquid, forming tiny water droplets in the sky.
  • Precipitation is when water droplets fall from the sky as rain, snow or hail.
  • Run-off is when water flows over the ground and into creeks, rivers and oceans.
  • Infiltration is when water falls on the ground and soaks into the soil.
  • Percolation is when water seeps deeper into tiny spaces in the soil and rock.
Natural water cycle diagram

The natural water cycle moves water from the Earth to the atmosphere - and back again.

Water is continually moving through the natural water cycle.

Earth has exactly the same amount of water as it had thousands of years ago. This cycle is also called the hydrological cycle.

We modify and manage part of the natural water cycle to provide humans with water. This is called the urban water cycle.
 

Have you ever wondered how water evaporates? Where clouds come from or where water goes after it rains? It’s all part of the water cycle.

We think the water cycle is amazing. It’s been recycling water from the Earth to the atmosphere and back again continuously for billions of years.

Check out our fun science experiments and create your own mini water cycles in a jar.

Make a cloud experiment

Have you ever looked in the sky and wondered how clouds are made? How did they get there? What are they made of? Try this experiment and Make a cloud to see a part of the water cycle in action.

Water evaporation experiment

Have you ever seen water disappear in front of your eyes? How does this happen? Where does it go? Try this experiment and explore how Water evaporation works and discover how water changes from liquid to gas.

Water cycle and terrarium experiment

Water doesn’t really disappear forever or magically appear as new water. How does it get in a cloud? Is rain new water? Create your own mini earth with our  Water cycle and terrarium experiment and discover how  water continuously recycles round and round.

Terrarium with molecules, outline and sun

Create a mini Earth and water cycle.


Need some Lesson Ideas. Check out our water cycle lesson plans.

Did you know?

  • Water is the most common substance found on Earth. It's the only substance found naturally in three forms – solid (as ice), liquid (as water) and gas (as water vapour).
  • Water is made up of tiny molecules. One water molecule, called H2O, is made up of three atoms - two hydrogen atoms and an oxygen atom. These atoms stick together due to electrical energy.
  • Water is a solvent, which means it dissolves things. Wherever it travels, water carries chemicals, minerals and nutrients with it. This means water is more than what we can see.
  • Water can be tested to see if it is acidic, basic or neutral. We like our water neutral. If water is too acidic or basic this is not good for our water pipes or your heating elements in appliances such as kettles and hot water systems.
Ph_scale_blue2

We use this test strip to tell us if our water is acidic, basic or neutral (pH 7).

Don't have a high-tech lab at school? Keen on science at home? Why don’t you try these fun experiments?

You don’t even need kids as an excuse, all you need is water and some household products!

Make a pH indicator experiment

Got a tired looking red cabbage in your fridge? Why not try this experiment using red cabbage as a natural pH indicator and test items around you home.

Find out what’s acidic, basic or neutral with our Make a pH indicator experiment.

Make a simple water filter experiment

Where did you get your water today? Was it clean and safe to use and drink? Sydney Water filters your drinking water every day, so you don’t have to!

Using random stuff around your home, try to Make a simple water filter and work out what makes a good filter.

Keep wipes out of pipes experiment

Urghh wipes! Did you know some people use the toilet like a rubbish bin?

Nearly one million people are flushing wet wipes and other items which don’t break down. That’s a problem for your pipes and ours.

Try our Keep wipes out of pipes experiment to see what breaks down, you may be surprised.

Wipes experiment 5 jars lined up with contents after being shaken

Do our keep wipes out of pipes experiment to see why only the three P's - pee, poo and (toilet) paper, can be flushed.  

  • The total amount of water on Earth is 1,386 million km3
  • Water covers about three quarters of the Earth’s surface.
  • 96% of the world’s water is saltwater. 
  • 3% is of the world’s water is freshwater, but most of it is frozen or not easy to get.
  • Less than one per cent of the world’s fresh water is useable.
Water on earth pie chart

Less than 1% of the water on Earth is useable for drinking.

Primary School

School students

We have a range of online water education resources for primary school teachers and educators.

See all our online primary school resources.

High school

Students drinking water

We have a range of online water education resources for high school teachers and educators.

See all our online high school resources.