Urban Stormwater Management
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Clean stormwater helps keep our creeks, rivers and lakes healthy. When rain falls on your home, garden or business, it runs into your downpipe or the nearest stormwater drain. The stormwater system then drains to the nearest creek, river, or lake, and is separate from the sewage system, which carries water from our sinks, bathrooms and toilets and sends it to a sewage treatment plant.
Stormwater is not treated to remove pollution before it reaches our waterways. This pollution can make our local water bodies unsafe to swim in and seriously damage our environment if we are careless about how we use and dispose of many substances.
Most stormwater pollution is caused by everyday activities, not by major spills or industrial accidents. That's why it is important for all of us to do our bit, especially in urban areas. What seems like a little bit of waste from your home or business is a very serious problem when multiplied by every house in town.
Stormwater pollution includes many human produced wastes such as litter, grease and oil, paint, garden pesticides, detergents, concrete and many products we use in our homes and at work.
Even seemingly ‘natural' waste, such as soil, sand, pet droppings, grass clippings and fallen leaves, can create major problems in our waterways because they become much more concentrated in our urban areas than they would be in nature.
Litter from our streets is washed into local waterways and typically includes plastic wrappers and cigarette butts, all of which take years to decompose and can choke or entangle aquatic animals. Litter also spoils the visual appeal of our rivers and lakes.
Leaves and grass clippings use up oxygen in the water as they decompose, suffocating fish and water animals.
Animal faeces often contains pathogens, including micro organisms such as viruses and bacteria, which can cause disease when washed into the waterway.
Nutrients from garden fertiliser, detergents and pet droppings can cause toxic algal blooms (blue-green algae), which release toxins that can harm wildlife, stock, pets and humans. Excess nutrients can also cause excessive plant growth - which can choke the waterway.
Toxins and heavy metals such as garden pesticides, herbicides, paint, motor oil and detergent all contain heavy metals and other poisons that harm aquatic life or cause disease. Pesticides and herbicides attack aquatic plants and animals in the same way that they attack your garden pests. Heavy metals can accumulate in shellfish and fish and can make them unsafe for humans to eat.
Soil and sand from gardens, building sites and roads can make water so turbid (muddy) that water plants don't get enough sunlight and die. It can reduce the oxygen dissolved in water, smothering aquatic animals. Sediment can also erode riverbanks and destroy habitat. Building sites often release plasterboard and concrete cuttings as sediment. Sediment soaks up heavy metals (such as lead) and other poisons as it travels.
Concrete can change the pH (acidity) of water, making it dangerous for fish and other water animals.
Oil and grease can leave a film on the water that sticks to plants and animals and makes it hard for them to breathe and swim. Even small amounts can do serious damage - one litre of motor oil will make one million litres (or an Olympic swimming pool) of water unsafe for plants and animals.
How can stormwater pollution be reduced?
We can all take action to reduce stormwater pollution from our homes and businesses and from public places such as parks. Contact Ararat Rural City Council on 5355 0200 for more information about what you can do around your home or business. If you see someone contributing towards stormwater pollution, you can report their action to the EPA’s Pollution Watch line on 1800 444 004.
For further information on stormwater go to the EPA's Stormwater website.