Reducing
Water
Pollution
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REDUCING WATER POLLUTION
The possible strategies to reduce water pollution can be a personal initiative or
controlled by government legislation. Understanding and early identification of
pollution problems can avoid future water pollution problems and its impact on
terrestrial environments. Reduction in water use will also reduce the likelihood of
waste run-off polluting problems.
Possible Strategies That Households Can Use To Reduce Water Pollution
Every time you wash your hands, flush the toilet or wash your clothes, you are
creating wastewater. Wastewater is simply water that you and everybody else throw
away – down the drain. It includes water from street drains, factory and farm drains
– drains everywhere.
As populations increase, the amount of wastewater to be treated grows. Water
authorities are struggling to keep up with the amount of water running through the
systems.
Question:
Make a list of all the possible ways of reducing wastewater from your
household.
Practical Activity: Perform a first hand activity to determine the amount of water
used per household for one activity: such as water used per toilet flush, water used
per shower, water used per washing machine cycle and identify ways in which this
could be reduced.
Write up this activity in your Prac. Book and hand it in for marking. Your text book
has an example of this activity. You have one week to complete this activity for
homework.
Conditions Under Which Algal Blooms May Occur In The Rivers Of NSW And
Impacts Of Algal Blooms in Rivers
Blue green algae, or Cyanobacteria, are the most ancient of all photosynthetic
organisms. Some produce poisons harmful to humans and possibly fatal to domestic
animals and fish, producing neurotoxins, liver toxins and skin allergens. A BlueGreen algal bloom is a rapid increase in the number of algae. It is noticed as it
discolours the water so the surface looks like green acrylic paint and has an
unpleasant odour.
An excessive level of nutrient phosphorus promotes rapid growth and multiplication
of the algae. This finds its way into our river systems from run-off from farms,
households and industry. Phosphorus can be found in our fertilisers, stock manure,
detergents and other household products. Warm water temperature also encourages
the algae to flourish, especially under calm summer conditions when water
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temperature is over 18 degrees. This causes warm lighter water over a layer of colder
water. The algae flourish in the warm surface water, and reduce oxygen levels at the
bottom assist in the release of phosphates from sediment, feeding the algae. Another
possible trigger can be a low level of zooplankton. These are microscopic animals
that live in the water and feed on the algae. When conditions are normal,
zooplankton keeps the level of algae under control.
http://www2.mdbc.gov.au/nrm/water_issues/water_quality/bluegreen_algae_in_the_river_murray.html
Alternative Strategies to the Use of Chemicals in Agriculture to Reduce
Water Pollution
Poisonous compounds to kill pests are called Pesticides. These can then be subdivided according to their target species – insecticides kill insects, herbicides kill
plants, fungicides kill fungi etc. Ideally, a pesticide would only be toxic to the target
pest species. In practice the degree of selectivity is very rarely achieved, which
means that ‘useful’ organisms are usually killed at the same time as the pest. For
example, a pest insect species may be preyed upon by another insect species, acting
as a natural control. If the whole area is sprayed with an insecticide, all the insects
will die and the predator ‘good’ insects won’t be around to eat the pests in the future.
Question:
Describe some alternative strategies that could be used rather than
chemicals such as pesticides, herbicides, fertilisers in Agriculture?
State Legislation Relating To Large Industry Sewage Treatment
Check out the Environmental Protection Authority - EPA. It is their job to monitor,
control and protect our environment, particularly water pollution control.
The Waste Minimisation and Management Act 1995 introduced a statewide scheme
for licensing waste activities. According to this scheme, the wastes that pose greatest
threat to the environment need a licence. The purpose of the licence is to ensure the
appropriate controls apply to the handling, storage, treatment and disposal of the
waste. These guidelines define which waste activities need a licence; outline the
obligation of those who need a licence; and set out the general environmental
obligations of those who do not need a licence.
There are cases in NSW where farmers are severely restricted in the amount and
times they can spray. This has occurred with cotton growers spraying the pesticide
Endosulfan. It has been found to enter the food chain and contaminate meat that
would make it unfit for human consumption.
References:
http://www.environment.nsw.gov.au/soe/soe2003/chapter5/
http://www.environment.nsw.gov.au/water/index.htm
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http://www.environment.gov.au/index.html
Question: Find 2 examples of technology being used and developed to reduce
water pollution.
Long Term Effects of Technology To Reduce Water Pollution
Long term methods of reducing water pollution will need to aim to prevent pollution,
reduce the use of energy, water and material resources and minimise waste, without
reducing production capacity and profitability.
The impact of technology on our understanding of pollution and its control has
increased as our understanding of the potential problems and improved technology
has been developed. The limits and methods of detection of water contamination are
improving to the point where even minute amounts of pollutants will be able to be
detected. Greater emphasis will be put back on preventing water contamination,
treating wastes and recycling.
The impact of technology on our understanding of pollution and its control are now at
a point where the limits and methods of detection of water contamination are
improving to the point where even minute amounts of pollutants will be able to be
detected. Greater emphasis will be put back on preventing water contamination,
treating wastes and recycling.
Question: Find an example of a technology that has had long term effects on the
reduction of water pollution and explain it effectiveness.
You may like to try some of these:
http://www.csiro.au/org/ps2i.html
http://www.unep.org/themes/freshwater/
http://www.water.org.au/index.htm
Water Pollution At The Local Level Impacts on Global Water
Example: Introduced Marine Pests from ships entering Australian waters.
The Australian Ballast Water Management Advisory Committee has identified seven
marine species as pests in Australian waters. Among these pests, the Northern Pacific
Seastar, Asterias amurensis, and the European green crab, Cancer maenas, occur
around the coast of Tasmania in numbers that cannot be controlled by physical
removal: there are an estimated 28 million Northern Pacific Seastars in the Derwent
estuary.
Read attached Marine Pest Information Sheet from the research done by the CSIRO.
http://www.marine.csiro.au/crimp/Reports/Infosht2_Ballastwater_A3S.pdf
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What Impact Does Pollution Have On the Water Cycle?
Water evaporated and carried into the atmosphere as vapour has an impact globally as
pollution can be carried great distances. What pollution is carried up to the
atmosphere it usually ends up as precipitation back on the earth, running off into our
streams, rivers etc. and eventually back to us. This can be found in the form of acid
rain.
Reference: http://www.sydneywater.com.au/
Question: Name one example where acid rain has occurred and the impact it had
on the environment.
Question: Name 1 policy from State and 1 from Federal government to minimise
water pollution.
Murray Catchment Area
Catchments are natural physical boundaries where surface water is directed into
rivers and streams by hills and ridges. Water from infiltration and run off is collected
in catchment areas. Infiltration is when water falls on the ground and soaks into the
ground. The water that does not soak in is called run off. Catchment areas are
the lowest point in an area. Water falling anywhere on the ground ends up in the
natural catchment area.
Natural Resource Issues:
 Reduced water quality
 Limited riparian management
 Soil erosion
 Decline in soil health
 Reduced biodiversity
 Degraded wetlands
 Poor floodplain management
 Hydrologic (water) imbalance
 Pest plants and animals
 Inefficient water use and water sharing - irrigation and urban.
 Managing cultural heritage
 Insufficient communication, information and education
 Limited long term natural resource management planning
 Insufficient support for community action
 Cross border interaction
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Possible areas where sources of contamination may enter the catchment
The "River Murray system" is:
 the main course of the River Murray and all its effluents and anabranches;
 tributaries entering the River Murray upstream of Albury;
 the Darling River downstream of the Menindee Lake storage;
 Commission works - Dartmouth Dam, Hume Dam, Yarrawonga Weir. Lake
Victoria storage, weirs and locks along the River Murray and lower
Murrumbidgee, and the barrages near the mouth of the River Murray; and
 the Menindee Lakes storage, which the NSW Government has leased to the
Commission in perpetuity.
Reference: http://www.mdbc.gov.au
Testing Water Quality
Safe and clean water is vital for healthy living practises as well as for consumption
and is one of the primary requisites for healthy human life.
Take a look at Streamwatch, a water monitoring organisation that monitors water
quality. http://www.streamwatch.org.au/cms/resources/
Practical Activity: Complete the activity of testing water quality at Finley Lake.
Get hand out worksheet from your teacher.
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