Clean Water News & Stories

From Unthinkable to Almost Drinkable

See how we clean the water you send down your home’s drains with an in-person tour or by diving in virtually. 

Toilets, sinks, dishwashers, bathtubs, and laundry washers — there are plenty of ways you use water at home every day. Do you wonder what happens to that water after you send it down the drain? Eventually, Washington County’s water ends up back in the Tualatin River, but it goes through quite a process to get there.  

Clean Water Services operates four state-of-the-art treatment facilities serving our region—Durham, Rock Creek, Hillsboro, and Forest Grove. We clean more than 65 million gallons of wastewater every day to some of the highest standards in the nation. The resulting water is of such high quality, it improves the health of the river. 

A CWS employee shares information about Durham Water Resource Recovery Facility outside over pools of water being treated.

See the treatment process in action at our upcoming facility tours this spring and summer. Tours at Rock Creek will feature resource recovery and energy production. Tours at Durham will highlight our cogeneration system that converts wastewater and food grease into clean, renewable energy. Both facility tours will provide a detailed, behind-the-scenes look at the treatment process. Register for a Durham tour here, or a Rock Creek tour here.  

The water we clean goes through several treatment phases. This includes removing everything from wipes and other trash to bacteria and pathogens you can only see under a microscope. At the Durham and Rock Creek facilities, we add a small amount of chlorine to kill any pathogens — making it as clean as drinking water. Then, we remove the chlorine to make sure the water is safe for wildlife before returning to the river. At the Forest Grove and Hillsboro facilities, we disinfect with ultra-violet (UV) light.  

The solids removed during the cleaning process will decompose in our holding tanks, or “digesters,” where we can recover essential nutrients for fertilizer, for use by farms, industry, and home gardeners. This minimizes waste, maximizes resources, and saves ratepayer money. You can explore our process in depth virtually

Your ratepayer dollars make it possible for us to protect public health and the environment in a challenging and sensitive watershed. Learn about the budget process we go through every January to June to ensure we can cover operating costs, maintain vital infrastructure, and prepare for future needs here.

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When you flush your toilet, everything in the bowl should (hopefully) be sent away from your bathroom and your home. For many people in Washington County, those contents head to a water resource recovery facility operated by Clean Water Services. For others, it is held in a septic tank.
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