For ordinary household use, only uncontaminated rainwater should enter stormwater unless the relevant authority has approved a specific discharge with conditions.
Keep cleaning water, paint or concrete washout, oils, fuels, chemicals, pool backwash, sewage, sediment, litter and garden waste out. Water that looks clear can still contain dissolved detergent, solvent, fertiliser, coolant or another pollutant.
Where does stormwater go?
Stormwater is rainfall runoff from roofs, roads, driveways, paths, gardens and other surfaces. It enters gutters, pits and pipes designed to carry that runoff away.
Queensland's environment department explains that most stormwater flows untreated to local creeks or rivers and eventually the ocean. Some networks include treatment devices, but householders should not assume an outdoor drain sends water to a treatment plant.
Sewerage is different. Wastewater from toilets, showers, baths, kitchen sinks and laundries travels through a sanitary system for treatment. Our guide to where household drains lead explains why the two systems must stay separate.
What counts as uncontaminated rainwater?
Rain falling onto a roof or paved surface and following the approved drainage path is ordinary stormwater. It can naturally pick up small amounts of ambient material, but that does not authorise anyone to add waste or contaminants.
Once water has been used to wash a vehicle, bin, floor, roof, tool, pet or equipment, treat it as wastewater. The same applies where runoff contains a product, visible sediment or waste from another activity.
Labels such as biodegradable, phosphate-free or non-toxic do not create permission to use a stormwater drain. The product may still affect waterways, and the correct disposal method depends on its ingredients and local requirements.
What must stay out of stormwater?
- Cleaning water: Keep detergent, disinfectant, degreaser and pressure-cleaning runoff away from gutters and outdoor drains.
- Paint and building washout: Contain paint water, plaster slurry, cement, concrete washout and sediment so none can wash into the drainage system.
- Vehicle fluids: Oil, fuel, grease, brake fluid and coolant need an accepted recycling or waste pathway.
- Garden chemicals: Do not tip fertiliser, pesticide, herbicide or concentrated garden products into drains or onto a place where rain can carry them away.
- Solid waste: Keep litter, leaves, grass clippings, animal droppings, food waste, soil and loose landscaping material out.
- Sewage and greywater: Toilet, bathroom, kitchen and laundry wastewater must not be connected or discharged to stormwater.
The Queensland Government's water-pollution guidance lists oils, chemicals, paint, thinners, coolant, pesticides, pool backwash, garden waste, animal droppings and litter as material that should not enter stormwater.
Do not assume the sewer is the alternative for every item. Paint, solvents, oils, pesticides and trade waste may require council approval, a product stewardship service or an appropriate waste facility. Check what should never be poured down a household drain before choosing a disposal path.
Can car-wash or pressure-cleaning water enter stormwater?
No deliberate wash water should run to the street gutter or a stormwater grate. Washing lifts oil, tyre residue, dirt, detergent and other material from the surface even when the water initially looks clean.
Plan the job so wastewater is contained and managed through a council-accepted method. Do not rely on dilution, a biodegradable detergent or a temporary screen as permission to release it.
What about paint, plaster or concrete water?
Keep these materials and their wash water completely contained. Brisbane City Council identifies soil, sand, silt, mud, concrete, paint, vegetation, green waste and cleaning products as building-site stormwater contaminants.
Use a designated contained wash area and an accepted waste pathway for the product and residue. Do not rinse tools over soil where runoff can reach a gutter, and do not hose settled material into a grate after the water looks clearer.
Can pool or spa water go down a stormwater drain?
Do not assume it can. Backwash and deliberate pool draining are subject to the property's connection, council rules and any approval conditions. The pathway for a property connected to council sewerage may differ from one using an onsite wastewater system.
For example, Logan City Council directs applicable pool and spa backwash to an approved wastewater connection and says it must not enter stormwater or a roadside gutter where that sewer connection is available. Emptying a pool is a separate approval decision.
Check the current council instructions for the exact property and equipment before releasing water. Do not copy a backwash routine from another council or assume a pool overflow authorises deliberate draining.
Can leaves or garden waste go into a downpipe?
No. Roof gutters and downpipes are part of the stormwater installation, not a waste chute. Leaves, grass clippings, mulch and animal waste can obstruct the system and carry organic material or microbes into waterways.
Remove loose material without pushing it into a grate or downpipe. If the issue is an actual obstruction, read how stormwater drains and downpipes become blocked. Do not test an unknown pipe by adding wastewater, dye or chemicals.
What should you do after a spill?
Stop the source and prevent more material reaching the drain only when this can be done safely. Keep clear of fumes, traffic, electrical hazards, floodwater and unknown chemicals. Do not mix, neutralise, dilute or hose the substance away.
Identify the product, keep its label or safety data available and contact the responsible authority for containment and disposal advice. Queensland's water-contamination reporting page directs most reports to the local council first. State authorities handle serious or material environmental harm within their remit.
Move away and call Triple Zero (000) if the release creates an immediate fire, explosion, toxic-fume, traffic or health danger. Avoid contact and restrict access if sewage or contaminated water has entered a gutter, waterway or public area.
What if you cannot identify the drain?
Do not use it until its destination is confirmed. An outdoor grate may connect to private stormwater, sanitary drainage, a surface channel or another system. Appearance alone is not enough.
Plans and visible pipe routes can help, but buried connections may need licensed investigation. The guide to finding stormwater drains on a property sets out safe ways to gather information without opening pits or introducing contaminants.
A licensed plumber or drainer can identify and correct a damaged connection or suspected cross-connection. Pollution cleanup and environmental incident response remain separate scopes and should go to the responsible council, authority or emergency service. If you need a private stormwater connection identified or a suspected cross-connection assessed, use our plumbing service to arrange a licensed plumbing and drainage inspection.