What is a brownfield?

What is a brownfield? Brownfields are properties that are either contaminated or that people think might be contaminated. Learn more about brownfields on this page.
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What is a brownfield?

According to the Environmental Protection Agency, a brownfield is a property on which the expansion, redevelopment, or reuse may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant. Many urban properties are brownfields because past uses may have left contamination.

Brownfields can be almost anywhere. They can be as small as a corner lot or can cover hundreds of acres. While some are easy to identify, they are often an invisible problem because contamination may be impossible to detect without a formal environmental site assessment.

Common examples of brownfields include former:

  • Gas stations
  • Auto repair shops
  • Dry cleaners
  • Industrial facilities
  • Warehouses
  • Vacant lots

The Agency for Toxic Substances and Disease Registry provides informational sheets about the common substances you might encounter on brownfields.

Two photos: At left, in black and white, an old photo of an auto repair shop. At right, in color, same location but of a restored floodplain on a rainy day.
A parcel of land that sits along Foster Road was once the home of several businesses including a service station, a mechanic’s shop, and a tire store. When the last active business closed, the property was considered a brownfield with petroleum in the soil. The City purchased the property and cleaned up the contamination. Today, the property is part of the Foster Floodplain Natural Area — a restored floodplain along Johnson Creek that holds extra water during heavy rains to reduce flooding to protect nearby properties.

What happens to brownfields?

Most brownfields can be reused for new businesses, housing, greenspace, or industry.  Many places we pass by every day in the urban landscape were once brownfields that have now been successfully redeveloped.  The Oregon Department of Environmental Quality (DEQ) provides guidance on how to assess brownfields and plan for reuse in a way that will protect people and the environment.

New use of a brownfield may involve any or all of:

  • Cleanup, like removal of contaminated soil.
  • Institutional controls: rules about site use to minimize exposure, like restricting use of groundwater.
  • Engineering controls: design decisions that minimize exposure, like physical barriers or venting systems.

Brownfields in Portland

There are many brownfields in every city, including Portland. Many of the vacant properties seen along Portland's busy commercial corridors may be brownfields. 

There is no definitive “map of Portland’s brownfields” because, for many properties, no one knows if contamination is present until an assessment is done on the individual site. However, there are several resources through Oregon Department of Environmental Quality that you can use to research a property in the state.

Two photos: At left, in black and white, a photo of empty warehouses. At right, in color, a multifamily building with a playground is in the same space..
This former manufacturing facility in Southeast Portland was once a brownfield. After an environmental assessment and cleanup, the site was redeveloped into affordable housing with support services for residents.

Why invest in brownfields?

Cleaning up brownfields:

  • Improves human and environmental health
  • Protects water quality
  • Increases the tax base
  • Makes land available for housing
  • Spurs economic development
  • Creates jobs
  • Saves on infrastructure expenses
  • Helps keep business in Portland.

Brownfields are often in efficient locations near other services and amenities, such as job centers, shopping, schools, health centers, transit, and housing. Environmental site assessment and cleanup can help turn brownfields into community assets.

According to the EPA, for every brownfield acre redeveloped approximately 1.3 to 4.6 acres of new impervious surface will not need to be built. This improves water quality associated with runoff from stormwater and nonpoint pollutant sources.

Redeveloping brownfields also reduces vehicle miles traveled. On average, residents living on or near redeveloped brownfields are likely to drive less, generating 7.3 to 9.7 fewer vehicle miles traveled per capita per day than if they lived in non-brownfield locations. This improves air quality associated with reduced greenhouse gas and other auto emissions.

Learn how the Portland Brownfield Program is helping revitalize brownfields in Portland.