Is it OK to wash our cars in the street or in our driveways? I thought I read somewhere that it’s not good if soap runs into the storm drains, yet I still see people out there scrubbing away every weekend. One of my neighbors even blows his grass clippings down the drain. What gives?

— Tanya, Medford

A Medford city ordinance forbids pouring, draining or allowing runoff of anything beyond water into a storm drain because the drains lead to Bear Creek and its feeder creeks, with no treatment in between.

That includes grass clippings, with can add to a nutrient load in Bear Creek that already exceeds healthful levels for juvenile wild salmon and steelhead that rear in the creek and its tributaries year-round.

The detergent from washing a car can cause algae to bloom and rob oxygen from fish in the creek. Violating the ordinance can carry a fine of up to $1,000.

That doesn’t mean it’s illegal to wash your car on a driveway, parking lot or street. It’s only a violation if the soapy water flows into a storm drain.

If the runoff water is collected and disposed of in a sewer system, absorbs into the soil or even evaporates on the street, it’s not a violation — although you should keep in mind that in the latter case, the chemicals that were in the water likely will wash down the storm drains eventually (in which case your police record may stay clean, but your conscience won’t).

Safe alternatives for washing your car at home include washing the vehicle on the lawn or other location where soil will absorb the runoff, or restricting the amount of water used by putting a spray nozzle on the end of your hose. Regardless of where you wash your car, you should use biodegradable soap.

And, of course, you can always go to a professional car wash, which is required to have a water reclamation system or send water through a treatment process.

Fundraising car washes are also a good choice as long as they are at locations such as Food4Less in Medford, which previously installed a reclamation system in its parking lot.

Avoiding runoff into the storm drains has taken on added importance in recent years, as cities along Bear Creek have intensified efforts to make the creek more hospitable for wild salmon and steelhead.

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