What is best for the environment - an automated car wash or hand car wash?

What is best for the environment - an automated car wash or hand car wash?
While we can't give you a conclusive answer on this, simply because we've never conducted any sort of study into it ourselves, we can outline some of the main issues. Car wash wastewater can contain phosphates, detergents, surfactants, oils, silts/
sediments, traffic film remover, rubber, copper and other metals. These pollutants can have a range of direct and indirect impacts, depending on the volume and frequency, the level of dilution and whether it flows directly into a watercourse. For example, the phosphates in detergents can ‘overfertilise’ the water with nutrients leading to excessive algae growth, consuming oxygen and killing animals and plants in large numbers. The number and severity of recorded water pollution incidents linked to vehicle washing is minor compared to agricultural pollution or water company incidents, but the detergents and vehicle dirt in wash water can impair water quality and have toxic effects on animal and plant life if disposed of incorrectly and not treated at a sewage works. Commercial vehicle washing businesses are legally obliged to follow specific guidelines on how to dispose of this water properly. Hand car wash operators are subject to the trade effluent provisions in the Water Industry Act 1991. Section 118 of the Act makes it an offence to discharge trade effluent to a sewer without the written consent of the local water company.

A House of Commons Environmental Audit Committee report covers these facts, and more, as well as includes this useful bit of info. Anglian Water told us that, in its experience, ‘very few hand car washes obtain a discharge consent prior to conducting business, this includes many hand car wash businesses which set up in supermarket car parks.’ Therefore hand car washes probably have a bigger environmental impact because they're less regulated.
Answered by Georgia Petrie on

Ask Honest John