Our Rivers, Lakes and Wetlands

Did you know all our waterways are connected? Let’s find out how healthy they are.

Click the links below to discover more!

Water is precious

Did you know that the water we have on Earth now is the same water that the dinosaurs drank?

We have a set amount of water on Earth: the amount of water doesn’t increase or decrease, it just moves through the atmosphere and the environment (this is known as the water cycle).

Water covers 70 per cent of the Earth’s surface, but most of this is saltwater in our oceans. Only about three per cent of the water on Earth is freshwater, and most of this is either frozen, in the air, or underground. Less than one per cent of the Earth’s water is freshwater that is available for people and animals to use – which is why it is so precious.

Because of differences in rainfall, some places have lots of freshwater, but in other places, such as deserts, there is almost none.

It is important that our water is clean and that there is enough of it for:

  • plants and animals
  • people (for drinking, growing food, washing, and having fun – like swimming or boating)
  • cultural reasons – the Murrumbidgee River (and other rivers in the ACT) represent Songlines and Dreamings for the Ngunnawal people.

ACT’S RIVERS, LAKES AND WETLANDS

The ACT’s largest river is the Murrumbidgee, which means ‘big water’ in the language of the Ngunnawal people, the first inhabitants of the land on which Canberra is located. This river begins in the NSW mountains and runs through the ACT. The Murrumbidgee is the second longest river in Australia!

Some other rivers in the ACT are the:

  • Cotter River
  • Gudgenby River
  • Molonglo River
  • Paddys River

Image: Murrumbidgee River, Photo: Mark Jekabson

Canberra has 3 lakes – Lake Burley Griffin, Lake Ginninderra and Lake Tuggeranong. These are man-made or constructed lakes and did not exist before Canberra was developed. There are also many other constructed ponds and wetlands in the Canberra area. These were mainly created to capture pollution and stop it getting into our rivers.

The ACT has 12 nationally important wetlands and the Ramsar-listed Ginini Flats Wetland Complex in the Namadgi National Park. Ramsar wetlands are those that have been recognised across the world as being very important because they are rare, unique, or home to lots of species. All wetlands are important for conserving biodiversity.

Catchments and main rivers in the ACT. Source: Bureau of Meteorology.
Significant wetlands in the ACT. Source: Bureau of Meteorology.

Do you know this waterway?

Click to find out!

The Cotter River

Jerrabomberra Wetlands

Lake Burley Griffin

The Murrumbidgee River

Ginini Flats Wetland

The Molonglo River

Images: Jerrabomberra wetlands by Raw Shorty, Lake Burley Griffin by Jerry Skinner, Cotter and Murrumbidgee Rivers and Ginini Flats Wetland by Mark Jekabsons, Molonglo River by Ryan Colley


Image: Cotter River by Mark Jekabsons | Canberra Drain

Healthy rivers, lakes and wetlands

We need to keep our rivers, lakes and wetlands healthy so people and the animals that live there have clean water. Water can be contaminated by pollutants – when we measure the pollutants in a waterway, it is called measuring the water quality.

Rivers, lakes and wetlands also need plants, because plants help keep waterways clean. Riparian vegetation help keep waterways clean by acting like a filter for nutrients, sediment and other pollutants. These are carried in water running off urban areas such as concrete and roads, or off farm paddocks that have livestock (sheep and cows) or use chemicals to help crops grow. When pollutants are washed into rivers, wetlands and lakes they affect the species living there. A healthy river also needs enough water flowing along it. This not only provides the habitat that plants and animals need, but also helps to keep oxygen in the water for the animals that live in it.

Image: Monitoring for waterbugs

HOW HEALTHY ARE OUR RIVERS, LAKES AND WETLANDS?

How do we measure the health of rivers, lakes and wetlands?

There are different ways to measure the health of rivers, lakes and wetlands, including:

  • measuring biodiversity – the types of plants and animals that live in the water, even little things like water insects (these are called macroinvertebrates). Healthy rivers, lakes and wetlands will have lots of native species in the water, and along their banks and edges.
  • measuring river flow – how much water is flowing in the rivers. Rivers, lakes and wetlands need to have enough water to stay healthy and to support plants and animals.
  • measuring water quality – healthy water is free from pollution that can harm plants and animals. Where water is used for recreation (fun activities like swimming, canoeing and fishing), we can also test whether water contains bacteria, blue-green algae or chemicals that could make people sick.

By looking at all these measurements, we can assess the health of the ACT’s rivers, lakes and wetlands.


ARE ACT’S RIVERS, LAKES AND WETLANDS HEALTHY?

The overall health of the ACT’s rivers and creeks depends on where they are. Rivers in conservation areas (parks and reserves) are mostly in good health because there are lots of trees and other plants which keep the water clean.

But rivers near urban areas and farms are less heathy. This is because most of the plants in these areas have been removed.

River flow changes are also impacting on the ACT’s rivers and wetlands. Because of climate change, there is now less rainfall and less water available for our rivers and wetlands. When there is less water for long periods of time, plants and animals can suffer as their food and habitats are lost.

water quality is mostly good in the ACT, even in rural (farming areas) and urban areas! But our recreational water quality can be poor. In the summer, recreational areas in our lakes and rivers can be closed because there is too much blue-green algae and bacteria in the water. These can make people sick if they get the water on their skin or if they accidently swallow the water. Most of the recreational and other water quality problems are from the pollutants washed into rivers and lakes by rainfall. urban areas and rural areas are where most of the water pollutants come from in the ACT.

Non-native, or invasive fish species such as carp, rainbow trout, brown trout and redfin perch are also a problem in the ACT. In some rivers, there are far more invasive fish than native fish. For example, up to 70 per cent of the fish in the Murrumbidgee River are invasive species!

WHAT ARE THE MOST COMMON IMPACTS ON THE HEALTH OF THE ACT’S RIVERS, LAKES AND WETLANDS?

  • Bushfires – after Bushfires, ash, soil and dead plants can be washed into rivers and wetlands. This can lead to poor water quality and the loss of plant and animal species. It can also impact on our drinking water reservoirs.
  • climate change – the Earth is warming and there are longer, hotter, drier droughts. This means less water for the ACT’s rivers, lakes and wetlands and the biodiversity they support.
  • invasive species – high numbers of invasive plants and animals compete for food and habitat with native species, and some invasive species can kill and eat native animals.
  • Clearing land for urban areas – land clearing removes the trees and other vegetation that help to keep rivers, lakes and wetlands healthy. Development of urban areas also means more concrete surfaces which increase water pollution and soil erosion, and reduce habitat for plants and animals.

Image: Sedimentation from fires

WHAT CAN WE ALL DO TO HELP KEEP OUR RIVERS, LAKES AND WETLANDS HEALTHY?

  • Use environmentally friendly dishwashing, shower and laundry soaps – think about the chemicals you are putting down the sink!
  • Use less water. Have shorter showers, recycle water, do less washing, water the garden less, install a rainwater tank.
  • Make sure that rubbish and garden waste goes in the bin or the compost – any litter dropped in the street can be washed or blown into our waterways.
  • Plant more native vegetation to reduce the amount of pollution going into our waters.
  • Clean up fallen leaves and other debris from gardens and streets, so that this doesn’t wash into our waterways.

A hands-on way to help local waterways is to join a volunteer community group. You could join the community WaterWatch program where you help monitor water quality, water bugs and river plants. Collecting information about your local waterway helps scientists better understand water across the ACT and Australia.

Note that most volunteering opportunities in the ACT will require you to be accompanied by someone over the age of 18.

LET’S GET OUTSIDE

Visit Jerrabomberra Wetlands to discover Canberra’s wetland wildlife.

Image: Jerrabomberra wetlands, Photo: Raw Shorty

Activities


MATCH THE DOTS

This activity shows how the health of rivers are connected to land use. Look at the map – the different coloured dots show us the health of different areas of the river catchments. Healthy catchments mean healthy, clean rivers, lakes and wetlands.

Healthy catchments have plenty of native vegetation to support the soil and reduce the amount of pollutants by filtering the water that runs off the land.

Data sourced from: Upper Murrumbidgee WaterWatch, based on Catchment Health Indicator Program score for Catchment reaches.

Think about it!

What types of land are the ‘excellent’ and ‘good’ quality catchments on? What type of land are the ‘fair’ (less than good) catchments on? Why do you think this is? How can we help to make ‘fair’ quality catchments better?


COLOURFUL FLOWERS

This activity shows us how plants help to keep our rivers, lakes and wetlands clean. Adult assistance required.

WHAT DO I NEED?

  • red, blue, green food dye
  • 3 vases, filled almost to the top with warm water
  • 3 white flowers, cut with a long stem (white chrysanthemums, carnations and roses work well)

Watch how flowers absorb colours!

Add 30 drops of red food dye to a vase of warm water. Repeat this, adding blue dye to another vase of warm water and green dye to a third.

Cut a little bit off the bottom of each stem, cutting on an angle to increase the surface area of the stem. Then place one flower in each vase and leave for a few days.

Watch over the next few days to see what happens to the colour of the flower petals.

Making colourful flowers is fun, but it also shows us how plants absorb what is in the water. Just like the flowers absorbed the colour, they also absorb chemicals and pollution that is in the waterways.

This is why they are so important to keep our waterways clean!

How much do you know about water and rivers?

This activity improves our general knowledge about water and waterways in the ACT. See if you know the answer to the questions. Hint, the answers are on this website! Once you think you know the answer, click on the card to see if you are right.

What is H2O? What does it stand for?

H2O is the scientific name for water. The ‘H’ is for hydrogen (there’s two of these atoms, in every water molecule). The ‘O’ is for oxygen (there’s one of these atoms, in every water molecule).

Name two types of pollutants that can affect waterways.

Pollutants include chemicals, too many nutrients, too much sediment (soil washed into waterways after rain), and bacteria from animal or human waste

What is riparian vegetation?

Riparian vegetation is the plants that grow on riverbanks and around the edge of lakes and wetlands.

True or false: It is important that rivers are flowing?

True. When there is less water for long periods of time, plants and animals can suffer as their food and habitats are lost.

The ACT’s largest river, the Murrumbidgee, unfortunately has some invasive fish species that affect native fish. Can you name one of these invasive species?

Invasive fish species include the Common Carp, Redfin Perch, Eastern Gambusia, Oriental Weatherloach, and goldfish.

What are 4 things we can do to keep our rivers, lakes and wetlands healthy?

1, Use less water. 2, Use environmentally friendly products. 3, Put rubbish and garden waste in the bin or the compost. 4, Join the Waterwatch program.