Where to wash the car

What most people do not realize is that the really responsible way to wash cars is at car washing facilities. Most people want to be environmentally responsible.

However, sometimes we find out that what we thought was green can be detrimental to the environment in ways that we have not imagined.

Most of us know that washing cars on the street or concrete driveways allows soapy water to run directly into storm drains and then into the rivers and streams to Puget Sound, thus hurting fish and wildlife.

What most people do not realize is that the really responsible way to wash cars is at car washing facilities.

Washing on the lawn is not the solution.

When we drive our car onto grass, hoping that the heavy metals and other harmful chemicals will be filtered out in the soil, we are actually harming the environment.

Driving vehicles on the lawn compacts the soil almost like concrete.

This contributes to more storm water runoff and extreme flow levels in our streams.

Compacted lawns do not filter storm water well, so the soapy water will eventually reach the storm drains anyway, carrying all the lawn treatments with it as well, while making the lawn look worn-out.

Additionally, “green” or biodegradable soap does not mean “non-toxic” for aquatic life. Biodegradable soaps can be toxic to fish and reduce stream oxygen levels, especially in the summer when people more often choose to wash their cars at home.

Adding soap to runoff from lawns, which is already contaminated with fertilizers and pesticides equals the worst toxic brew for any inhabitant of water, especially during the summer months when stream flows are low.

Warm stream water is already oxygen deficient without additional loads of wastewater.

A much better alternative is to pay a little extra and use a commercial car wash that recycles its wash water.

Or install a pervious wash area that is designed to filtrate wash water safely.

A pervious wash pad, such as TurfgridTM, consists of three inches of top soil/lawn in pavers and four inches of sand bedding to filter the soapy water.

The sand filters detain the wash water with soap, petroleum products, and other pollutants from the car, to be broken down by bacteria.

Another benefit of pervious pavements is the overwinter recharge of the shallow sub-surface aquifers that help maintain summer stream base flows.

Rain that falls in winter and is infiltrated into the ground is slowed and reaching the streams in the summer when the water is needed most.

Currently, most runoff from lawns and other impervious surfaces is discharged to Puget Sound; and therefore, not available to help the streams in the summer.

Pervious pavement surfaces can help.

To learn more about sustainable lifestyles in Snohomish County, see sustainablesnohomishcounty. net

The Sustainable Development Task Force of Snohomish County is a non-profit organization of professionals who provide free advice to homeowners, developers and contractors who want to live green and protect streams and salmon runs.

SDTF will present its annual Sustainability Fair in Maltby at the Snoqualmie Gourmet Ice Cream Factory on Sept. 10, 12:30-4 p.m.