COVID-19: Many City facilities and all playgrounds are closed. View our City Facilities and Parks Status Map to see what's open.
Get the latest coronavirus updates on our COVID-19 webpage. Para actualizaciones en español, visite nuestra página de Noticias.
PPE Grants Open: Apply for the Hillsboro Protective Equipment Grant for small businesses. Solicite una subvención para pequeñas empresas.

Building Flushing

Flushing Guidance and Checklist for Buildings

The City of Hillsboro Water Department delivers safe, high-quality water that is not impacted by the COVID-19 virus to our customers' service connections.

Building owners are then responsible for the water in the building plumbing systems. Water left sitting in pipes when buildings are closed, or in low use situations, will stagnate and may cause water quality problems and health risks, including:

  • The growth and spread of Legionella and other harmful bacteria.
  • Lower than usual levels of chlorine disinfectant, which keeps water safe from bacteria.
  • Leaching of lead and copper out of pipes and fixtures.

The Oregon Health Authority (OHA) advises building owners to take precautions before resuming regular building use to ensure safe water and protect public health.

Oregon Health Authority Tips

    1.  In general, flush one area and fixture at a time, starting in the basement and working upward to other floors.
    2. Remove aerators and flush cold water first, then hot water.
    3. Be sure the hot water heater is set to at least 120 degrees Fahrenheit.
    4. Consider collecting one or more coliform bacteria samples after flushing and having the samples analyzed by a local water testing lab.

Each building is different and will require different actions based on its plumbing system and use patterns. The Center for Disease Control has developed a Guidance for Building Water Systems website with eight steps to take before your business or building reopens

And remember—building water management isn’t just for after a long-term closure. Flushing is an ongoing best practice.

Once you have completed your water system refresh, notify employees and let customers and others using your building know the steps you are taking to ensure the water is safe. Post a sign or send an email—they will appreciate hearing from you.


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