The Real Scoop on Washington State’s Car Washing Rules

By Kevin Miller


Earlier this week, USA Today picked up on a story I’ve been hearing rumblings about for several weeks: a ban on personal car washing in Washington State. Any law that might prevent me from washing my own car in my own driveway is something I need to know about, since washing my cars on a sunny Seattle day is one of my favorite activities.

So here’s the deal. When you wash your car, the wash water contains whatever soap you use, plus the dirt that is washed off of your car, including metallic dust from your brakes, and any automotive fluids which may have precipitated on your vehicle. As the car is washed, suds are sprayed off of the car, and typically flow downhill toward the nearest storm drain.

The Washington State Department of Ecology (WSDOE) states that soapy, dirty car wash water, carrying with it oils, grease, and toxic metals is a serious pollution source when considered on a large scale, such as on a sunny afternoon when thousands of regional residents wash their cars. Since most storm drains run directly into local streams or marine waters – without treatment – storm drains can be considered direct extensions of those bodies of water.

The Department of Ecology is responsible for issuing stormwater permits to municipalities in the state, and those permits now require cities and counties to adopt regulations prohibiting liquids other than stormwater from being discharged into a storm sewer system. Those prohibited fluids include the suds washed off of a car in your driveway.

The Department of Ecology is requiring these ordinances be enacted as a condition for continuing to issue water runoff permits to cities and counties. The WSDOE actually publishes a guide for local governmental organizations to develop ordinances against illegal wastewater; both “soaps” and “detergents” are on the list of substances which are illegal to be discharged into stormwater drains.

As the media hype over this story has been reaching a crescendo, Jay Manning, Director of the Washington State Department of Ecology, issued a letter to leaders of local governmental organizations to clarify the state’s stance on car washing, stating “Some believe that our stormwater permits “prohibit” residential car washing and wonder what, if any, enforcement actions might be taken against those “violating” the prohibition. Let me be clear: the permits do not prohibit car washing. The permit only deals with discharges to storm drains. In this case, that means that wash water, which contains soap, oils, grease, metals and other chemicals – all of which pollute water and harm fish – is prohibited from being discharged to public storm drains.”

The Department of Ecology recommends washing cars on grass or any other surface where the wash water seeps into the ground. Alternately, something can be laid on the ground to divert the wash water away from the storm drain. And, of course, the state reminds residents that they can take their vehicles to a commercial car wash.

In his letter, Mr. Manning also states “I want to further clarify that while the permits do not allow soap and detergents to enter a storm drain, we recommend an educational rather than enforcement approach about car washing. We definitely don’t recommend enforcement against charity car washes.”

Officials in the Stormwater Services department in King County, which includes Seattle, are writing a proposed ordinance to ban home car washing if the runoff goes into storm drains. The rule is expected to pass this fall and is said to have local support.

All of this means that Washington residents can still wash our cars, we just need to wash them somewhere other than our paved driveways if those driveways drain to stormwater systems. As more cities and counties get these required ordinances on the books, it will be interesting to see how diligently they are enforced. It will also be interesting to see if other regions follow Washington State’s lead. As I’m not willing to give up my sunny afternoons of car washing, I’ll need to figure out a way to divert my car wash water away from my local storm drain.

COPYRIGHT Autosavant – All Rights Reserved

Author: Kevin Miller

As Autosavant’s resident Swedophile, Kevin has an acute affinity for Saabs, with a mild case of Volvo-itis as well. Aside from covering most Saab-related news for Autosavant, Kevin also reviews cars and covers industry news. His “Great Drive” series, with maps and directions included, is a reader favorite.

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  1. That is just unbelievable.

  2. Seriously, while I live in Arizona, not Washington, I always wash my car on the lawn. Why waste all that watter when the grass could se it?

  3. I’m glad you figured this one out. Sounds much more handle-able than the original stories that the Oregon media were putting out. I guess I’d never thought about washing a car on the grass…does the soap kill the grass? (It isn’t yet as diluted as it is when it joins large bodies of water, is all I’m saying, I’m not saying grass is more important than fish.)

  4. This has long been the recommendation/rule/law elsewhere, such as in Michigan, Germany and Sweden.
    Makes sense, even if it’s a bit inconvenient.

  5. There’s not much in detergent that’ll kill grass….in fact it’ll help it grow cause of the phosphates and surfactants. Much better on your grass than in your rivers and creeks.

    Feel fortunate that you can even wash your car. Water restrictions here in my part of Australia due to the neverending drought mean that the only way we can wash cars at home is via a bucket……no hoses. The alternative is the local car wash. Former is time consuming, latter is expensive, dirt roads are everywhere & dust storms are not infrequent…Upshot is that my car hasn’t been clean for a very long time.

  6. Puget Sound-area car owners without access to a yard might use commercial car washes where most of the water is reclaimed since that, too doesn’t go into the storm drains. Some (the chain with the bear-themed name and some car dealers’ washes for customers, e.g. Barrier) claim they recycle/clean almost all of their wash water. Seems like ALL commercial car washes should have to comply but haven’t heard of such policies.

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