Augering- An auger is a corkscrew like device with extended horizontal plates that collects excavated material. The auger is screwed into the ground, collects material, and is then raised out of the hole. The auger is rotated in the opposite direction at the surface, allowing the soil to fall off the auger.

BDS – Bureau of Development Services – serves customers by providing over-the-counter permits, building permit application and review, and locate permit and case history on property located in the City of Portland.  Staff from BDS includes plan reviewers, land use planners, structural engineers and technicians available to answer your questions and review your plans.

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BES – Bureau of Environmental Services - The Commissioner of Public Utilities oversees the Bureau of Environmental Services, a branch of Portland’s city government. Environmental Services maintains and operates the sewer system—pipes and pump stations that collect and move the city’s sewage and stormwater—and two wastewater treatment plants. The Combined Sewer Overflow Program (CSO) is a division of Environmental Services.

Bio-swale - A landscape swale is a long, gently sloping, landscaped depression that collects and cleans stormwater. When it rains, water runs over pavement and other hard surfaces, picking up pollutants along the way. Much of this polluted stormwater runoff goes to storm drains and into our rivers and streams. Landscape swales collect and slow down stormwater.  The soil and plants in these swales can filter and clean water before it drains into sewers, groundwater, rivers, and streams.

BPS – Bureau of Planning and Sustainability –  promotes integrated land use planning and development based on sustainability principles and practices. BPS also develops and implements policies and programs that provide environmental, economic and social benefits to residents, businesses and government, which strengthen Portland's position as an international model of sustainable practices and commerce.

CBO – The Community Benefit Opportunity Program provides funding for community projects in neighborhoods and business districts affected by the CSO construction program. 

CBWTP – Columbia Boulevard Wastewater Treatment Plant – Located at 5001 N Columbia Blvd, the plant operates every day, around the clock. The staff is specially trained to manage, monitor and adjust the treatment process. Dozens of pump stations and hundreds of miles of sewer lines are part of the system that brings wastewater to the facility 24 hours a day.

The Tryon Creek Wastewater Treatment Plant, a second wastewater treatment plant south of Portland, is also monitored at the Columbia Boulevard facility.

CDF - Controlled Density Fill (CDF) is a self-compacting, cementitious (having the properties of a cement) material used primarily as a backfill in lieu of compacted backfill (backfill:  to refill an excavation)

Clamshell - A bucket-like device attached to the crane and lowered into the trench. The bucket (clamshell) is lowered open, the bucket closes to grab the soil, and the bucket is lifted to the surface, opened, and the excavated materials dropped into the waiting truck.

CSO - Combined Sewer Overflows occur nearly every time it rains in Portland. During a CSO, stormwater quickly fills the combined sewers, which carry both sanitary sewage and runoff from streets, parking lots, and rooftops. The overflows carry bacteria from the untreated sewage as well as other pollutants in the stormwater into the Willamette River.

CWA - The Clean Water Act (CWA, 1972) is an amendment on the Federal Water Pollution Control Act (1948) which contains the basic rules for pollution discharge into water. The CWA was established to repair and preserve the chemical, biological and physical quality of all water (including oceans, lakes, rivers, streams, groundwater and wetlands) in the United States of America. Through the CWA, EPA has gained the authority to establish standards for water pollutions.

DEQ - The Oregon Department of Environment Quality is responsible for protecting water quality and manages the Federal permit system for sewage treatment plants. The City of Portland’s CSO Program works with DEQ to meet the schedule and requirements of the Amended Stipulation and Final Order (ASFO), a legal agreement for reducing the pollution caused by overflows.

Downspout Disconnection - In conventional construction, roof runoff flows through gutters and downspouts to a drywell, storm sewer or combined sewer. Disconnecting downspouts helps keep clean roof runoff from overloading the sewer system when it rains. Roof runoff can be redirected to a yard, garden, swale, or stormwater planter, or to a rain barrel or cistern for storage.

Downspouts can be disconnected on residential, commercial and industrial properties. The system you choose can be as simple or complex as your goals and site requirements allow.

An ecoroof (extensive roof or green roof) - is a lightweight vegetated roof system used in place of a conventional roof. Ecoroofs are typically made of a synthetic waterproof membrane, a drainage layer, a maximum 6-inch layer of soil, and a cover of plants. Choose species appropriate for a rooftop environment - dry and hot in summer, wet in winter. Ecoroofs are not intended to be accessed except for maintenance, unless walkways or plazas are incorporated into the design.

Empeller Dredge - An Empeller Dredge is a device with two big fans (short augers) attached to the bottom of a suction hose. The fans rotate and mix the soil with water and the soil/water mix is vacuumed up the suction hose to the surface.  It is used to excavate the rest of the shaft after a certain depth and it is filled with water.

EPA – Environmental Protection Agency .  The mission of the Environmental Protection Agency is to protect human health and the environment. Since 1970, EPA has been working for a cleaner, healthier environment for the American people.  The President of the United States appoints the Administrator of the EPA.  EPA leads the nation's environmental science, research, education and assessment efforts.

Force Main – A sewer line fed by a lift station (a type of pump that brings the wastewater up to a certain level), which carries pumped wastewater to a point where other pumps or gravity can take over.

Green Streets - Landscaped Stormwater Curb Extensions -Historically Portland has built curb extensions to improve pedestrian safety. A new variation called a stormwater curb extension is landscaped with plants that help filter pollutants from stormwater runoff. They have similar benefits to the conventional curb extension but they also improve water quality, reduce stormwater flow, and enhance the aesthetic look of a neighborhood. 

Ground improvement involves drilling several holes under each bridge and injecting concrete into the ground below the bridge foundations. The result will be an underground block of hardened soil and concrete. The tunnel will pass through or next to the concrete block.

Guide walls are temporary concrete walls at the ground surface that define the inside and outside face of the wall excavation. The guide walls define the slot/trench for the slurry walls or secant piles. The guide walls prevent the trench from eroding at the surface when the excavation tools are entering and leaving the trench

A Hydromill is a crane-mounted excavator with rotating wheels used to excavate a slot/trench for the slurry wall panels. The wheels mix the soil with slurry and the mixture is pumped to the surface.

Infiltration planters are structures or containers with open bottoms to allow stormwater to slowly infiltrate into the ground. They contain a layer of gravel, soil, and vegetation. Stormwater runoff temporarily pools on top of the soil, and then slowly infiltrates through the planter into the ground. Infiltration planters come in many sizes and shapes, and are made of stone, concrete, brick, plastic lumber, or wood. Infiltration planters are not recommended for soils that don’t drain well. Use flow-through planters instead.

Interceptor sewers catch or ‘intercept’ CSOs before they can reach the river. An interceptor built alongside an existing interceptor in order to provide more capacity is called a ‘parallel interceptor.’

Jet Grouting - With the jet grouting process, a drill hole is placed in the ground. A drill rod equipped with jet nozzles injects high-pressure water, air, and cement into the ground as the drill rod is rotated and raised. The high-pressure materials cut/loosen a circular column of soil, which mixes with the cement and forms a column of soil/cement material with increased strength and lower permeability.

Microtunneling - is used to construct small tunnels. These small diameter tunnels make it impossible to have an operator in the machine itself. Instead, the microtunnel boring machine or MTBM must be operated remotely. Usually the operator controls the machine from a control room on the surface of the ground.

Microtunnel Boring Machine (MTBM) - They are very similar to tunnel boring machines but on a smaller scale. These machines generally vary from 24” to 60” but smaller and larger machines have existed. The main differences between MTBM and TBM operations are: MTBM is operated by remote control, and MTBM usually has the tunnel liner pushed behind the machine instead of built as the machine advances.

ONI – Office of Neighborhood Involvement - The Office of Neighborhood Involvement, (ONI), was established in 1974.  The office serves as a communication link between residents, neighborhoods, and City of Portland bureaus. 

Open Cut or Open Trench - an excavation, usually a long deep trench, made on the surface for the purposes of mining or tunneling.

OTF – Overflow Treatment Facilities are wastewater treatment plants designed to operate only during rainy weather when CSOs would otherwise occur. Portland’s OTFs will provide primary treatment and disinfections of overflows before discharge into the Willamette and Columbia Rivers.

Outfalls - CSO outfalls are the pipes that spill overflows into the Willamette River or Columbia Slough. Not every pipe that empties into the river or slough is a CSO outfall. Some carry stormwater runoff or cooling water from industries. All outfalls must have a permit from DEQ before they can discharge anything into the river or slough.  Some older pipes, usually from private property and not part of the sewer system, continue to operate without permits. City staff are working to determine who is responsible for unpermitted discharges in order to stop any pollution they cause.

PDC – Portland Development Commission - Created by Portland voters in 1958. During the past 40+ years, PDC has taken forward 20 urban renewal plans that have helped change the face of the city.

PDC does waterfront redevelopment, small business loans, affordable housing, new retail opportunities, transit-oriented development, business recruitment and retention.All graphics below this are for use in modern, standards compliant visual browsers. Please ignore them.

Portland Parks & Recreation is responsible for: 

1) Establishing and safeguarding the parks, natural resources, and urban forest that are the soul of the city, ensuring that green spaces are accessible to all;
2) Developing and maintaining excellent facilities and places for public recreation, building community through play and relaxation, gathering, and solitude; and
3) Providing and coordinating recreation services and programs that contribute to the health and well being of residents of all ages and abilities.

PDOT – Portland Office of Transportation - The Portland Office of Transportation is responsible for planning building, managing, maintaining Portland’s transportation system.

Pervious asphalt consists of coarse stone aggregate and asphalt binder, with very little fine aggregate (a cluster of soil granules not larger than a small crumb). Water percolates through the small voids left in the finished asphalt. A thick layer of gravel underneath allows water to drain through quickly. Pervious asphalt looks similar to conventional asphalt, although with a rougher surface, which accounts for its common name “popcorn mix.”

Pervious concrete consists of specially formulated mixtures of Portland cement, open-graded coarse aggregate, and water. It has enough void space to allow rapid percolation of water and resembles exposed aggregate (a cluster of soil granules not larger than a small crumb) concrete.

Pervious pavers - are typically made of pre-cast concrete, brick, stone, or cobbles.  Pavers usually form interlocking patterns, and are placed within a rigid frame on top of a sand bed or an under drain system. Sand or gravel fills the gaps between pavers, allowing water to pass to the underlying subgrade then infiltrate into the ground. Some pavers also have small voids in the pavement surface to increase permeability. Pervious pavers are available in many colors, shapes, sizes, and textures, and can support heavy traffic loads and weights.  They can replace conventional asphalt or concrete paving in parking lots, roads, and sidewalks.

River Alert is Portland’s system to notify the public when an overflow has occurred. Between May and October, large yellow signs are opened when a CSO has been reported to the computerized detection system. The signs remain open until 48 hours after the overflow event ends. During the winter months, the signs remain open to remind river users that overflows may occur anytime it rains. A River Alert information line (503-823-2479) offers additional information, allows a caller to leave a message or add their name to a mailing list, or find out if an overflow has occurred.

A roof garden (intensive roof) - is a heavyweight vegetated roof system used in place of a conventional roof. Roof gardens typically consist of a waterproof membrane, drainage layer, and a thick layer of soil (typically 12 inches or more), vegetation, and hardscaping to allow access to the garden (e.g., planters, stepping stones, benches).

Because a roof garden can support pedestrian traffic, it can be designed as a building amenity, with walkways, terraces, plazas or seating areas. It differs from an ecoroof by its greater soil depth and weight, accessibility, and the greater range of plants it can accommodate.

Secant Piles - Secant piles are two piles (vertical holes filled with concrete) placed side by side. One pile cuts into the second pile (overlapping), so the two are in direct contact with each other. The overlapping section is the "secant." Secant piles can be placed in a series, each cut into the adjacent pile, forming a wall. The walls can be made in a circular or rectangular pattern and hold back the soil when the inside is excavated.

SFO - In August 1991, Portland officials signed the Stipulation and Final Order, a legal agreement between the City and the Oregon State Department of Environmental Quality that details the steps necessary to eliminate the water pollution caused by CSOs. The agreement was changed in 1993, and is now referred to as the Amended SFO or ASFO. Under the agreement, Portland will eliminate nearly 94% of the CSOs that now affect the Willamette River and more than 99% of the overflows into the Columbia Slough.

Slurry - A dense mixture made up of bentonite clay and water.  It is used to fill holes (shafts, building slurry walls, tunnels, etc.) to prevent collapse.

Click here for Slurry Wall Graphic

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Stone Column - Water is jetted into the ground forming a large vertical hole. The hole is filled with gravel (stone) from the surface. The hole ends up as a column filled with stone. Stone columns are used to create greater density or hardness to the ground and provide drainage paths in the event of an earthquake, releasing water pressure during an earthquake.

TBM – Tunnel Boring Machines are used to excavate tunnels with a circular cross section through a variety of geologies. They can be used to bore through hard rock orsandand almost anything in between.  TBMs are used as an alternative to drilling and blasting.

Tremie Plug or Tremie Mat - An excavation is created and held open with a slurry (clay/water mix). A "tremie" pipe (open pipe) is lowered to the bottom of the excavation. Concrete is placed into the pipe and allowed to drop through the pipe to the bottom of the excavation. The concrete begins to form a pile at the bottom, displacing the slurry out of the excavation. The pipe (tremie pipe) is raised slowly allowing the excavation to be filled with concrete. This process is used for the slurry wall panels, for secant piles, and for the bottom slab ("plug") at each shaft. The bottom slab is a "plug" designed to prevent water from entering into the shaft from the bottom.

Turf block (grass grid, open-cell unit paver, geoblock)- consists of interlocking concrete or plastic cells filled with soil and planted with turf grass or a low-maintenance groundcover. Water passes through the turf block into a reservoir base of crushed aggregate, then infiltrates into the subgrade. Turf block accepts precipitation only, not stormwater runoff. It is available in a variety of colors, shapes, sizes, and textures. Turf block is best suited for areas of low traffic and infrequent parking, such as patios, walkways, and terraces, residential driveways; overflow parking areas, emergency access roads, and street shoulders.

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WB - The Portland Water Bureau operates the water supply system that delivers drinking water to more than 787,000 people who live in the Portland metropolitan area. The primary water source is the Bull Run Watershed located 26 miles east of downtown Portland, Oregon in the Mt. Hood National Forest. Portland also uses groundwater as a supplemental water supply.

The Water Bureau is a rate-financed, City-owned utility.