Gross Pollutant Traps (GPT)

Gross Pollutant Traps (GPTs) are filters that catch stormwater pollution before it has a chance to enter waterways. GPTs catch most of the litter and silt but don’t stop chemicals going into the environment. The contents of the GPTs are emptied on a regular basis and sent to landfill.

What are gross pollutants?

Items classed as gross pollutants are:

• Domestic plastics (plastic bags, clingwrap etc)
• Industrial packaging
• Metals (aluminium)
• Plastic bottles
• Paper (including) cigarette butts
• Sediments
• Organics (grass and garden clippings etc)

How this issue affects you

By trapping the majority of solid stormwater pollution, GPTs aid in enhancing the aesthetic qualities of the Hawkesbury environment. If areas are free of gross pollutants it is possible to enjoy recreational activities such as swimming, boating and waterskiing.

How this issue affects the environment

Stormwater pollution can kill plants and animals that live in the water. For example:

• Sediment in the water reduces light penetration and affects photosynthesis, the process that allows plants to use light as their source of energy
• When green waste decays in water it uses up oxygen, taking vital oxygen away from plants, fish and other aquatic animals
• Soil makes waterways cloudy and can suffocate fish by clogging their gills
• Litter clogs waterways and causes toxicity as it breaks down. It affects the health of birds, fish and other animals and plants that live in the waterways

What you can do to help

The most effective way to reduce this problem is to prevent pollution entering the stormwater system in the first place. This is better for the environment and cheaper for the community as traps have to be regularly cleaned, emptied and maintained, and this cost can be greatly reduced if there is less pollution entering the stormwater systems.

• Traps don't catch all the silt or litter, and they don't stop chemicals. Things you can do to help include:
• Never allowing chemicals or dirty water to enter street stormwater drains
• Keeping rubbish in covered bins at all times (including cigarette butts) and away from stormwater drains
• Washing and servicing vehicles on grassy areas or in car wash bays
• Keeping leaves and grass clippings out of stormwater drains
• Collecting dog droppings and placing them in the bin
• Sweeping workshop floors and paved areas instead of hosing

Council Responses

There are 21 underground inline GPTs located in the Hawkesbury City Council Local Government Area. The locations of the GPTs in operation are:

• Arkell Drive 
• Bensons Lane (x2)
• Castlereagh Road 
• Colbee Park
• Dight Street 
• Fairey Road
• King Road (x2) 
• King Street
• Macquarie Street 
• Mileham Street
• Mileham Street – opposite Brabyn Street 
• Mileham Street – opposite Day Street
• Mileham Street – opposite Forbes Street 
• North Richmond Community Centre
• Terrace Road 
• The terrace – opposite Baker Street
• The terrace – opposite Kable Street 
• The terrace – opposite Fitzgerald Street
• The terrace – opposite Johnston Street 

The table below shows the Gross Pollutant Trap results since January 2009.

For the years 2009 -2011 a total of 298.35 tonnes of gross pollutants have been collected.

For 2011– 91.2 tonnes of gross pollutants were collected.

Pollutants are defined as litter, sediment or organic. On average 65% of total waste removed is organic, 20% is sediment and 15% is litter.

For any further inquiries please contact the Waste Management Manager on 02 4560 4519

References: http://www.environment.nsw.gov.au/stormwater/whatis/index.htm