Car Washing
Car Washing Impacts Water Quality
When a car is washed in a driveway or street, this water flows untreated directly into the storm drain, and then into the local waterways. Essentially, it’s like washing the car in the San Joaquin River .
A study of the wastewater generated from fundraising car wash events identified pollutants in the wastewater, including:
- Petroleum hydrocarbons (i.e. gasoline, diesel fuel, motor oil, fluids, and lubricants) from automobile engines, leaks, and fuel combustion processes
- Heavy metals from normal wear of auto brake linings (copper), tires, exhaust, and fluid leaks
- Phosphorous‐ and nitrogen‐containing detergents from cleaning vehicles, which cause nutrient loading
- Surfactants from detergents and cleaning formulas (synthetic and organic), which are used to help loosen dirt or grease
- Solids from vehicle exteriors and surfaces
Wash Your Car on the Grass or at a Carwash
While it isn’t illegal for individual residential car washing to occur in your driveway, there are ways to protect water ways.
- Washing the car on the lawn allows the water to be absorbed by grass.
- A Commercial carwash directs the used water to treatment systems, and in many cases, they recycle it.
Biodegradable Soap
Unfortunately, using biodegradable soap doesn’t solve the problem:
Most pollutants found in the study did not come from the soap.
Biodegradable helps the treatment of wastewater, but it requires oxygen to break down in a river ‐ restricting availability to aquatic life.
You Can Make a Difference
Encourage your friends, family, and neighbors to wash their cars on the lawn or at a commercial carwash.
Find alternatives to fundraising carwashes. Some options on how to conduct an environmentally-friendly car wash are listed below. In all cases use a flow-control device such as a hand spray with an on/off hose trigger to conserve water.
OPTION #1 HOLD YOUR CAR WASH IN A GRASSY FIELD INSTEAD OF A PAVED PARKING LOT
Wash all vehicles on a permeable surface such as a grassy or gravel lot, using biodegradable, phosphate- free soap. Soil and plants help to filter out toxins before they seep into groundwater. Never allow wash water to enter the storm drain system.
OPTION #2 FIND A SPONSOR FOR YOUR CAR WASH THAT USES A CLOSED LOOP WASHING SYSTEM
Preferably you want one that recycles its water. These are generally industrial and commercial sites designated with an equipment/vehicle wash area. Wash pads must be directly connected to the sanitary sewer system. The property owner is responsible for all necessary discharge permits. Do not hold your car wash at a facility that is not properly equipped. Popular sites such as service stations and parking lots usually do not have the necessary connections to the sanitary sewer.
Remember! – Discharges on to the ground or into the City of Lathrop’s storm drain system from organized car washes (i.e. fundraising car washes) is prohibited.
Tips on Environmentally Friendly Car Washes
Links:
Be Fresh Water Friendly
