Poo, Plastics And Pesticides

By Nicola Saltman on October 21, 2014 in Other

We’ve all heard it before: plastic and pollution can screw up our environment. Did you know that in every square kilometre of ocean, there are more than 18,000 pieces of plastic, and that plastic bags and discarded litter can kill sea turtles and other unsuspecting marine life?

Then there are the nasties you cannot see, like the invisible threat of microplastics that lurk in our waters, as a study released by the Sydney Institute of Marine Science last month revealed. These tiny fragments of plastic – from broken down clothing fibres, bags and bottles – have been found for the first time among the smallest grains of sand in Sydney Harbour. It’s a potentially poisonous situation for fish and other sea creatures, and we don’t yet know what impact these nasties may have on us.

All sorts of pesky pollution winds up in our coastal waters through the drains on our streets – think dog poo, discarded paint, detergents and herbicides. It’s all collected by the rain that falls on our rooftops, roads, footpaths and parklands, which then drains into the stormwater system. This watery concoction flows through a series of underground pipes and open channels, and empties out at our beaches. Typically, stormwater is untreated, so what goes in comes out to pollute our coastline and threaten our wellbeing. A whopping 95% of litter on our beaches comes from this stormwater system. It’s scary to think what has ended up in our oceans after all the recent rain!

What are the main sources of stormwater pollution and why do they suck?

Rubbish – Cigarette butts, plastic, cans and paper can clog pipes. Depending on the type of litter, toxins can be released into the ocean as the products break down.

Chemicals – Detergents, fertilisers, pesticides, cooking oils and grease can be toxic to humans, animals and plants.

Natural pollution – Leaves and garden clippings can clog waterways and reduce the amount of oxygen available to animals, fish and plants for survival.

Animal droppings – Animal poo can increase the nutrients available in the sea, which affects marine animal and plant health.

Sediment – Soil erosion and runoff from building sites can block sunlight required for plants to grow and can also clog fish gills.

Bacteria – This poses a serious health risk to humans and may be present in polluted stormwater. That’s why it’s suggested you don’t take a swim at the beach immediately after it has been raining.

How can you help?

The most sure-fire way to reduce stormwater pollution is to stop it entering the drain in the first place. With National Water Week being celebrated this month (October 19 to 25), it’s the perfect time to do the right thing by our oceans (and our health).

1. Use less plastic, and dispose of it properly.
2. Sweep gutters and driveways rather than hosing them down.
3. Put leaves and grass clippings in a compost or green recycling bin.
4. Wash your car on the grass with a small amount of soap and pour the remaining soapy water down the sink or onto the grass.
5. Pick up your dog poo and dispose of it in a rubbish bin.
6. Bin your cigarette butts and other litter.
7. Follow fertiliser instructions so that you don’t over-fertilise.
8. Sweep up fertiliser bits on the footpath and pop them into a rubbish bin.
9. Dispose of oil-based paint and other chemicals at Chemical Cleanout Days.
10. Rinse water-based paint in a sink or on the grass.

Locally, Waverley Council has set up stormwater harvesting systems at Bondi and Bronte beaches to capture, treat and reuse some of the stormwater to irrigate our parks and for public toilets.

Council has also just completed three rain-garden projects in Bondi Junction to help clean stormwater that drains to Centennial Park’s ponds. Rain-gardens look like regular gardens, but they’re actually natural stormwater treatment systems. They’re designed to capture and filter run-off from driveways, roofs and roads, and are also self-watering, thus requiring very little maintenance. Check them out at the corner of Gray Street and Bronte Road, and another along Hollywood Ave.

For more information, visit www.waverley.nsw.gov.au/environment/water_and_coast or check out www.awa.asn.au/nationalwaterweek.