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The City of Portland, Oregon

Environmental Services

working for clean rivers

Phone: 503-823-7740

Fax: 503-823-6995

1120 SW 5th Ave, Suite 613, Portland, OR 97204

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Clean Rivers Vocabulary

Clean Rivers Education Vocabulary

  • Aquatic - Organisms (plant or animal) living in the water all or part of their lifetime
  • Bioswale - A long, gently sloping depression or ditch planted with vegetation that slows stormwater runoff and allows water to drain into the ground or be absorbed by plants. This process breaks down, filters, and removes many stormwater pollutants
  • Combined Sewer Overflow (CSO) - Stormwater and sewage that mix in combined sewer pipes and overflow to the Willamette River when it rains
  • Downspout Disconnection - Redirecting roof runoff from the combined sewer system to lawns and gardens
  • Ecoroof -  A lightweight, low-maintenance vegetated roof that absorbs rain and reduces stormwater runoff. Ecoroofs also reduce the heat island effect that warms the air over cities and naturally insulate buildings to reduce energy use
  • Erosion - The wearing down or washing away of the soil and land surface by the action of water, wind, or ice
  • Fertilizer - Animal waste or chemicals that help plants grow. Fertilizers that wash into rivers and streams can cause overgrowth of aquatic vegetation and reduce oxygen levels
  • Green Street - Landscaped curb extensions in streets or landscaped areas next to streets that slow stormwater runoff and allow water to soak into the ground and be absorbed by plants
  • Groundwater -  The water stored in pores, cracks, and openings of subsurface rock. An aquifer is an underground formation that stores and conveys groundwater
  • Herbicide -  A substance used to kill plants, especially weeds
  • Impervious - A surface that water can’t penetrate, such as streets, buildings, and parking lots
  • Naturescaping - Landscaping with native plants that require less water and little or no fertilizers or pesticides. Native plants are low maintenance because they are adapted to our environment
  • Pervious -  Pervious surfaces allow water to soak easily into the ground allowing more groundwater recharge, reducing pollutants and cooling streams
  • Pesticide -  A substance used to destroy insects, slugs, rodents, weeds and other pests. Pesticides include both insecticides and herbicides
  • Stewardship -  Taking care of the earth for ourselves, for others, and for future generations; sharing knowledge and enthusiasm about that care with others
  • Stormwater -  Rainwater after it reaches the earth
  • Stormwater runoff - Water from rain or melted snow that runs over land surfaces. Stormwater runoff picks up soil, pesticides, cigarette butts, litter, oil, dissolved metals and other pollutants and washes them into storm drains, rivers and streams
  • Sewage -  Liquid and solid waste from residential and commercial drains and toilets
  • Wastewater -  The used waters of the community (see Sewage)
  • Watershed -  An area that drains to a specific waterbody. All activities within a watershed affect river and stream health
  • Wetlands -  Areas where the soil is saturated long enough during the growing season to impact the nature of soil development and the types of plant and animal communities