Wellington City Councillor Iona Pannett applauded Porirua's move but said there were no plans to introduce a similar bylaw in the capital.
"People don't understand that the water they wash down the street goes somewhere. I guess I would rather take an educational approach before we start thinking about any bylaws."
In Auckland a stormwater bylaw comes into force in November that doesn't ban washing cars on private properties but allows the council to make such a move if there was a specific area of concern or need to do so. There are no plans to make such a ruling.
Waikato Regional Council spokesman Stephen Ward said the council agreed that letting chemicals used in car washing go down the drain into the stormwater system risks the health of waterways and coastal areas.
"We strongly encourage people to wash their cars on the grass or do them in a car wash." Tauranga has a bylaw banning contaminants in its stormwater system and has education campaigns about car washing.
