It’s the suburban dream – driving to the car wash on a Saturday morning, sipping a coffee inside your vehicle while it’s sprayed, foamed, flannelled, rinsed, blow-dried and buffed like a prize poodle. You and your car emerge from the ablution and all’s right with the world.
Cleaning is good, right?
The thing with car washing, at a car wash or at home, is that it’s not just dead flies and muck that are coming off.
“Dirt, brake dust, oil and traffic film residue that are washed off vehicles are all pollutants,” says Uisce Éireann.
‘Traffic film residue’ is the term for the accumulation of oil, fuel, brake fluid and other motor vehicle fluids that get leaked onto roadways by cars and end up on everyone’s cars. When you wash your car, this is what’s flowing off.
What else?
Some car washes offer spectacularly elaborate cleansing rituals.
One 12-step programme comprises this dizzying sequence: ‘rainfall foam pre-soak’, ‘rim prep’, ‘under chassis wash’, ‘high pressure wheel wash’, ‘premium wash’, ‘full contouring high pressure wash’, ‘rainshield surface protect’, ‘VIP drying’, ‘premium foam polish’ and ‘brush polish buffing’. Add holy water and a blessing and you’ll have reached Nirvana.
It sounds like a whole lot of water and more besides. Next time your kid wants to stand and watch at the car wash, keep walking.
Where is ‘away’?
Washing stuff away can feel good, but where exactly is ‘away’? It’s not some magical place where things just get ‘disappeared’. ‘Away’ can mean into the air we breathe, the water supply and the soil.
Well-managed car washes will have special drainage systems. Where these aren’t in place, the polluted run-off from washing can end up in rivers, streams, the sea and in groundwater, damaging our water quality, habitats and wildlife.
High levels of pollutants discharged into the sewer in an uncontrolled way can hamper the sewer network and wastewater treatment plants.
What can I do?
The best way to minimise the effect of car washing is to keep washing to a minimum, says Uisce Éireann.
When you do wash your car, use a licensed car wash, but also ask them what they are doing to reduce and reuse water and stop pollutants entering the environment.
Car wash operators that discharge wastewater into a public sewer must have an Uisce Éireann effluent discharge licence. Car washing must be in a designated washing bay, so that the run-off is not flowing to surface water drains that lead to rivers, streams, and the sea.
The washing bays should have an impermeable surface to prevent effluent soaking through the soil and polluting groundwater.
Washing bays should have a gradient and drainage to direct run-off to silt traps or settlement tanks where oil can be removed.
Washing at home
If you’re washing your car at home, use the minimum amount of water, says Uisce Éireann. Hoses and high pressure washers use a lot. Minimise cleaning products and don’t use a traffic film remover. Dilute any chemicals according to the instructions to avoid high concentrations in wastewater.
Don’t wash your car where run-off could enter or be washed by rain into surface water drains.
When you’re finished, empty the bucket into the foul water sewer – those are the drains in your house carrying wastewater from toilets, sinks, showers and washing machines to sewage works for treatment. Waste water shouldn’t contain oil or hazardous chemicals.
Save money
Car washing can cost from €10 to €50, so you’ll save money and save the environment by doing it less. Avoid service station loyalty schemes promoting ‘buy six car washes, get the seventh free’ – they’re good for service station coffers, but not for the environment.
If you’ve got a dirty car, drive it with pride. It might be time to rethink shiny, regularly washed vehicles – being clean can actually be pretty dirty.