Where does your car-wash water go?

Before you wash your car, look at where the water will go. Detergent, oil and road grime washed into a stormwater drain can reach streams and the sea without treatment.

Biodegradable does not mean drain-safe

A biodegradable detergent can still pollute waterways. Wash water also carries contamination from the car, so the label on the shampoo does not make that runoff suitable for a drain.

Choose a suitable place to wash

Where local guidance permits, grass or other unsealed ground can absorb runoff. Concrete, asphalt and paving cannot. Check the slope and nearby drains before starting.

Auckland Council suggests washing over unsealed ground or diverting runoff towards it with sandbags. If your driveway or apartment parking area cannot accommodate that, consider a car-wash site with suitable wastewater handling. Read Auckland Council’s home car-washing guidance.

If you wash cars for work

Plan containment and disposal for your site. Wash mats, collection tanks and approved disposal arrangements may be part of that setup. Do not assume that redirecting water onto land or into a sewer is automatically permitted.

Check stormwater and trade-waste requirements with your local council or wastewater provider before choosing a system. Auckland’s guidance describes covered, contained wash bays and permission for commercial discharge to the sewer. Read the vehicle and equipment washing guidance.

Check the requirements where you are

Rules and suitable disposal options depend on the location and activity. Look up your council’s current vehicle-washing, stormwater or trade-waste guidance. Contain or divert runoff only where permitted, and keep detergents and contamination out of waterways.