Blue Mountains City Council

Student Information
Local Environment

Information for students about the unique environment that makes up the Blue Mountains.



Student Assignments: Information about the local environment

The Blue Mountains Local Government Area (LGA) lies within the internationally recognised Greater Blue Mountains World Heritage Area.

This page contains information for students about the unique environment that makes up the Blue Mountains LGA. Topics are listed below in alphabetical order.


What is biodiversity?

Biodiversity (or biological diversity) is the variety of all living things in all forms. This includes the plants, animals, microorganisms, their genetics and the ecosystems they are part of.

The different geology, soil types, climates and altitudes in the Blue Mountains have led to a high diversity of plants and animals. There are at least 946 species of native plants and 327 species of native animals within the Blue Mountains Local Government Area (excluding the National Park).

There are six main vegetation types in the Blue Mountains that occur in distinct locations linked to aspect, exposure to the elements (light, rain, and wind), soil types and how close they are to water. These are warm temperate rainforest, wet sclerophyll forest, dry sclerophyll forest, grassy woodland, heathlands and freshwater wetlands (Blue Mountains Swamps).

Why is biodiversity important?

We rely on biodiversity and healthy ecosystems to provide food, oxygen, clean water, fertile and balanced soils, and even new soil.

Click here for more information about biodiversity in the Blue Mountains.

For more information about Blue Mountains vegetation types visit the Blue Mountains National Park website.


Australian plants and animals have evolved to survive specific natural fire regimes. A fire regime is characterised by the intensity, frequency, season, size and type of fire.
Changing fire regimes due to human impacts and climate change can be harmful to the environment. In the worst case plants and animals may become extinct if fire regimes change faster than they can adapt.

Click here for information about Council's bushfire management program and for links to other useful websites.

Climate Change

Evidence shows that global average temperatures have increased significantly in the last 100 years due to increased greenhouse gases in the atmosphere. This phenomenon is known as global warming.
The four most common greenhouse gases are Carbon dioxide (CO2), Nitrous oxide (N2O), CFC-12 and methane. Our growing population, industry, agriculture, landfill, burning of fossil fuels and more cars on the road all contribute to increased greenhouse gas emissions and global warming.

Global warming can result in higher temperatures, less rainfall in some areas and more extreme weather patterns (including prolonged drought or severe storms and floods). Global warming can also lead to changed fire regimes and in some areas more frequent and intense bushfires and a hotter, longer fire season. Many native plants and animals are sensitive to temperature, rainfall and fire so changes can lead to loss of biodiversity and even extinction.

Australia's average temperature has increased by about 0.9C since 1950, coastal rainfall in southeast and southwest Australia has decreased significantly, and parts of Australia have experienced prolonged periods of drought.

Green Power

Household electricity consumption is a significant cause of greenhouse gases in Australia. This is because the majority of our electricity comes from unrenewable and depleted resources such as coal. Adopting the use of renewable energy sources, termed Green Power, reduces greenhouse gases in the atmosphere as clean, renewable sources do not produce greenhouse pollution.

See download to your right for more information:

  • Green Power: Frequently Asked Questions

If you are looking for more information about climate change try these websites:


The Blue Mountains is one of the world's great sandstone Mesa formations. The Blue Mountains is a plateau with deep incisions (or gaps), different to conventional mountains. It rises from less than 100 m above sea level to 1300 m at the highest point. The sandstone is more than 200 million years old and was shaped over time by the interaction of water with stone.
The older Hawkesbury sandstone geology dominates in the Lower Blue Mountains in the east and Narrabeen Sandstone dominates the west. Basalt outcrops occur on the higher ridges.

For more links to information and diagrams of the geology and landforms of the Blue Mountains visit:

Land Degradation

Urban development has resulted in land clearing, fragmentation of bushland and loss of habitat, high volumes of stormwater, erosion, and sedimentation.

Land Clearing

Clearing and fragmentation of bushland has resulted in isolated pockets of remnant vegetation in urban areas. These remnants often suffer from pest and weed invasion, and are vulnerable to disease, inappropriate fire regimes and further clearing.

When habitats decline, animal populations decline and lose their genetic diversity as they compete for remaining resources. This reduces their ability to compete, fight disease or adapt to changing conditions. Habitat loss and fragmentation is one of the major causes of species extinction.


The typically sandstone soils in the Blue Mountains are highly susceptible to erosion in heavy rainfall. This is even more significant where urban development has led to increased velocity of stormwater flows in creeks and streams. Erosion can lead to poor water quality, weed invasion and habitat degradation.

Land Contamination

Land contamination occurs when high levels of chemicals harmful to the environment or human health exist in the soil. This may occur where in the past there has been a service station, fuel depot, landfill or gasworks on a site or where chemical fertilisers, herbicides or pesticides have been used in agriculture.

See downloads to your right for more information about land degradation:

  • Being A Good Bush Neighbour
  • Fact Sheet: Drinking Water From Streams
  • Fact Sheet: Dumping Garden Waste
  • Fact Sheet: Sedimentation


Blue Mountains Swamps are an Endangered Ecological Community due to their limited distribution and their vulnerability to disturbance and degradation. Swamps are an important part of the Blue Mountains water cycle and act like huge biofilters, trapping sediments and pollutants and purifying the water that passes through them. Swamps soak up water and release it gradually to provide a continual supply of moisture to downstream ecosystems.

Blue Mountains Swamps also provide habitat for many animals including Blue Mountains threatened species such as the Giant Dragonfly and Blue Mountains Water Skink.

See downloads to your right for more about Blue Mountains Swamps:

  • Fact Sheet: Blue Mountains Swamps and Swampcare
  • Fact Sheet: Fauna of Blue Mountains Swamps
  • Fact Sheet: Threats to Blue Mountains Swamps
  • Fact Sheet: Water Cycle in Blue Mountains Swamps

Threatened Species

Approximately 10% of the listed threatened species of New South Wales can be found in the Blue Mountains Local Government Area (LGA). Five of these are endemic species only occurring in the Blue Mountains LGA and include the Blue Mountains Water Skink, Blue Mountains Dwarf Mountain Pine (or Microstrobos, Pherosphaera fitzgeraldii), Epacris hamiltonii, Leionema lachnaeoides and Eucalyptus copulans.

See downloads to your right for more about threatened species:

  • Endangered Species: Blue Mountains Water Skink
  • Endangered Species: Epacris hamiltonii
  • Endangered Species: Giant Dragonfly
  • Endangered Species: Leionema lachnaeoides
  • Endangered Species: Microstrobos fitzgeraldii
  • Threatened Species: Township Information

Click here for more about threatened species in the Blue Mountains.

Waste Management


Recycling is the collection, sorting and reprocessing of discarded goods to create the same or a different product. Recycling reduces waste and helps protect our environment. It is important to understand the entire process to help us make it more effective.

We may be able to increase the quality of recycled products by reducing any contamination of the materials. Contamination occurs when items that cannot be recycled are mixed with those that can. These contaminating items can cause problems in the recycling process and make the recyclables unacceptable for reprocessing at the Materials Recovery Facility.

Waste Reduction

Waste can be reduced at home by composting, worm farming, mulching and low waste gardening. Many food products and garden waste can be composted. This prevents waste from going to the landfill (or tip) where it produces harmful greenhouse gases and leachate (contaminated water) that can pollute the environment.

Waste Management Facilities

Council operates two Waste Management Facilities in the Blue Mountains that offer waste disposal services to the Blue Mountains community. These facilities are located at Katoomba and Blaxland.

See downloads to your right for more about waste management in the Blue Mountains:

  • Fact Sheet: About Your Recycling Service
  • Fact Sheet: Blaxland Waste Management Facility
  • Fact Sheet: Katoomba Waste Management Facility
  • Fact Sheet: Recycling Correctly
  • Recycling: Frequently Asked Questions
  • Reduce Your Organics

Click here for more about Council's waste management program.


What are our water resources?

A catchment is a geographical area that collects and drains water to a waterway. The Blue Mountains Local Government Area (LGA) lies within the nationally significant Hawkesbury-Nepean catchment which currently supplies 80% of Sydney's drinking water. The catchment is named after its major river, the Hawkesbury-Nepean River.

Surface water (rivers, creeks, dams and lakes) and groundwater (water stored beneath the ground) make up the catchment's water resources.

The major waterways within the Blue Mountains LGA are the Grose River, Cox's River, Glenbrook Creek, Erskine Creek and Kedumba River. The major lakes and dams are Glenbrook Lagoon, Wentworth Falls Lake, Cascade Dam, Woodford Dam, Lake Graves and Lake Medlow.

Why is water important?

Water is vital for supporting healthy ecosystems and all forms of life. Blue Mountains waterways support a diverse range of aquatic and terrestrial ecosystems and supply water for drinking and for agricultural, industrial, recreational and commercial activities.

What are the major impacts on water?

Urban development has led to changes in the way water drains and flows into the natural environment. Hard surfaces (like footpaths and roads) stop water from soaking into the ground and cause stormwater run-off. Stormwater run-off causes erosion and sedimentation of waterways as water flows faster and in larger volumes.

Water quality is reduced by stormwater if it is polluted (by high nutrient levels, chemicals, sediment, rubbish, etc), contaminated water from sewerage and landfill (tips), and by erosion and sedimentation.
Population growth means more water is consumed by humans and water supplies are limited, especially in drought.

See downloads to your right for more information about Blue Mountains waterways:

  • Fact Sheet: Drinking Water From Streams
  • Fact Sheet: Groundwater
  • Fact Sheet: Iron Bacteria
  • Fact Sheet: Macroinvertebrates
  • Fact Sheet: Sedimentation
  • Fact Sheet: Waterfowl in the Blue Mountains
  • Information Sheet: Glenbrook Lagoon
  • Information Sheet: Wentworth Falls Lake

For more information about Blue Mountains waterways and their unique biodiversity and Council's water quality monitoring programs visit Council's Living Catchments web page.
If you are looking for more detailed information try these websites:


Weeds are plants that do not occur naturally in the bush. They compete with native plants and often dominate or replace them. They degrade and destroy the habitat of our native animals.

See downloads to your right for more about weeds in the Blue Mountains:

  • Fact Sheet: Being a Good Bush Neighbour
  • Fact Sheet: Dumping Garden Waste

Click here for more about Council's Weed Management Program and for weeds fact sheets.

Visit the Weeds of the Blue Mountains website for more information about the impacts of weeds in the Blue Mountains, how to identify weeds and how weeds invade.

Need more information?

Download more information and fact sheets from right.

Navigate the topics at left if you want to find out more about the Blue Mountains environment.

Visit our School Assignments: Information about the local area and Council for a guide to additional resources such as interactive maps, local population profiles, statistics and library help available to students.