Table of Contents Previous Next


Accessory Housing/Accessory Dwelling

Dwelling units constructed within an existing single-family home, usually for use as a rental unit. An “accessory dwelling” is another separate dwelling, including kitchen, sleeping, and bathroom facilities. Also known as an “in-law apartment.”

Affordable Housing

Affordable housing is generally defined as housing where the occupant in paying no more than 30 percent of gross income for housing costs, including utilities, and meets the needs of moderate- or low-income households.

Allowed Use

Means a permitted use or conditionally approved use.


Giving non-conforming land uses a period of time to recoup their investment before the use must be discontinued.


The act of adding an area into legal jurisdiction of a city.


An area of water-bearing soil or rock.

Arterial, Collector

An arterial street which collects and distributes traffic from higher use arterials (principal and minor) to local streets or directly to traffic destinations. Collector arterials also serve trips which both start and end within a neighborhood.

Arterial, Minor

An arterial street which serves as a distributor of traffic from a principal arterial to collector arterials and local streets, directly to secondary traffic generators such as community shopping areas and high schools, and serves trips between neighborhoods within a community. Minor streets are more intensive than collectors, but less intensive than principal arterials.

Arterial, Principal

An arterial street which connects regional arterials to major activity areas and directly to traffic destinations. Principal arterials are the most intensive arterial classification, serving major traffic generators such as the Central Business district, major shopping and commercial districts, and move traffic from community to community.

Assisted Housing

Owner-occupied or rental housing units which are subject to restrictions on rents or sales prices as a result of one or more project-based government subsidies. Assisted housing does not include holders of non-project-based Section 8 Certificates.

Attached Single-Family Housing

Two adjacent single-family houses on separate lots with one attached common wall.

Bicycle Facility

An improvement designed to facilitate accessibility by bicycle, including bicycle trails, bicycle lanes, storage facilities, etc.


A ditch with plants that is designed for a specific storm to filter sediment out of stormwater runoff.

Capital Facilities

As a general definition, structures, improvements, pieces of equipment or other major assets, including land, that have a useful life of at least 10 years. Capital facilities are provided by and for public purposes and services. For the purposes of the Capital Facilities Element, capital facilities are water facilities, sewer facilities, stormwater facilities, fire and rescue facilities, government offices, law enforcement facilities, parks, open space, recreational facilities, libraries, public health facilities, public housing and public schools.

Capital Facilities Plan

A general plan that identifies and balances capital expenditures and revenues for 10 to 15 years and demonstrates the viability of the Land Use Plan. The Capital Facilities Plan is part of the Capital Facilities Element of the Comprehensive Plan.

Capital Improvement Program (CIP)

A six-year plan for future capital expenditures which identifies each capital project, including anticipated start and completion dates, and allocates existing funds and known revenue sources. The CIP is updated and adopted annually as part of the City budget.

Capital Improvements

Projects to create, expand or modify a capital facility. The project may include design, permitting, environmental analysis, land acquisition, construction, landscaping, site improvements, initial furnishings and equipment.


Two or more people sharing the use of a vehicle between fixed points on a regular basis.

Characterized by Urban Development

Residential uses with an average gross density of more than one unit per acre, commercial uses, office uses, manufacturing uses, and similar uses of an urban nature or intensity.

Clean Air Act

Federal legislation requiring air quality goals for urbanized areas and State Implementation Plans to ensure that urbanized areas are working toward achieving those goals.

Clustering/Cluster Development

A development design technique that concentrates buildings in specific areas on a site to allow the remaining land to be used for recreation, common open space or preservation of environmentally sensitive areas.


A system of pipes which collect wastewater via downhill flow from on-site plumbing to the public sewer.

Commercial Use

The use of a building, land or other structure for non-residential and non-personal use involving retail sales, wholesale sales, office uses, entertainment uses or similar uses.

Community Development Guide

The City of Redmond document that includes the City’s adopted Comprehensive Plan, development regulations and building regulations. Also know as the Development Guide.

Commute Trip

A trip made from an employee’s residence to a worksite for a regularly scheduled work day.

Commute Trip Reduction (CTR)

A requirement of the Washington State Clean Air Act that requires major employers to develop and implement programs that will reduce the number of times their employees drive alone to work. The goals of commute trip vehicle miles traveled per employee and proportion of single-occupant automobile are a 15 percent reduction by January 1, 1995, a 25 percent reduction by January 1, 1997, and a 35 percent reduction by January 1, 1999.

Comprehensive Plan

A generalized, coordinated land use policy statement of the City Council adopted under the Growth Management Act (GMA) to guide future City decision-making. Redmond’s Comprehensive Plan is in Chapter 20B.20 RCDG.


A GMA requirement that the transportation facilities needed to maintain adopted level-of-service standards for arterials and transit routes are available within six years of development. The procedural guidelines recommend that concurrency requirements be considered for other public facilities and services in addition to transportation.

Conditional Use/Conditionally Reviewed Use/Conditionally Approved Use

A use that requires approval through the general development permit process or the special development permit process.


A condition under which the number of vehicles using a facility is great enough to cause reduced speeds and increased travel times.


A measure of whether any feature of the Comprehensive Plan or a regulation is incompatible with any other feature or a plan or a regulation. The GMA requires that the Comprehensive Plan be both internally and externally consistent.

Countywide Planning Policies

As required for GMA, the King County Council adopted, and the cities ratified, a series of policies which embody a vision of the future of King County. These policies are intended to guide the development of City and County Comprehensive Plans.

Critical Wildlife Habitats

Those habitats which meet any of the following criteria:

(a) The documented presence of an endangered, threatened, sensitive, candidate or other Priority Species as designated by Washington State or federal agencies;

(b) Type I wetlands as defined by Redmond’s sensitive areas regulations; or

(c) Class I streams as defined by Redmond’s sensitive areas regulations.


See Commute Trip Reduction (CTR).


A drain, ditch or conduit, not incorporated in a closed system, that carries drainage water under a driveway, roadway, railroad, pedestrian walk or public way.

Debt Capacity

The amount of debt that a city can incur. The State has set legal debt limitations for cities. However, a city also has practical limitations on its ability to issue debts that result from the need to obtain approval of the city’s voters, the cost of capital (interest rates), the desire to maintain a good credit rating and other factors.

Debt Financing

A method of raising revenue for capital projects which involves a city selling tax-exempt municipal bonds and incurring debt. The principal and interest in the bonds are repaid over time with property taxes or other revenues.

Decibel (dB)

A unit of sound pressure level. Decibels are used to express noise level.

Demand-Response Service

Transportation service designed to carry passengers from their origins to specific destinations (such as curb-to-curb or door-to-door) on an immediate demand or advance (e.g., 24-hour) reservation basis.


The number of families, persons, housing units, jobs or buildings per unit of land usually expressed as “per acre.”

Density Bonuses – Housing

Incentives provided to a developer in order to encourage the construction of affordable housing units. The developer is allowed to build more units on a site if a certain number of housing units affordable to low-income households are provided.

Detached Single-Family House

A residential building containing one dwelling unit entirely surrounded by open space on the same lot.


The process of collecting and holding back stormwater for delayed release to receiving waters.


The division of a parcel of land into two or more parcels; the construction, reconstruction, conversion, structural alteration, relocation or enlargement of any structure; any mining, excavation, grading, landfill, drainage, removal of vegetation, or disturbance of land or water; and use of land or water or the intensification or extension of the use of land or water.

Development Regulations

Any controls placed on the development or land use activities by a city including, but not limited to, zoning ordinances, official controls, planned unit development ordinances, subdivision ordinances and binding site plan ordinances. Redmond’s development regulations are in the Community Development Guide.

Development Right

The right to use or develop property for some economic purpose. Residential occupancy is a type of economic purpose.

Development Standards

In respect to any development, fixed requirements or standards imposed by regulation or ordinance. A setback is a development standard.

Discretionary Land Use Reviews

A land use review process, approval or permit where Redmond has the discretion to approve, approve with conditions or deny the request based on whether the proposal complies with the Comprehensive Plan or development regulations. Examples include Comprehensive Plan amendments, rezones, subdivisions, site plan reviews, SEPA reviews, special development permits, general development permits, conditional use permits and variances.


The act or process of delivering electric energy, water, natural gas, etc., from convenient points on the transmission system to the customers. Also, a functional classification describing that portion of the utility facilities or plan used for the purpose of delivery.

Drainage Basin

An area which is drained by a creek or river system.


A single structure containing two dwelling units, either side by side or above one another.

Dwelling Unit

One or more rooms located within a structure, designed, arranged, occupied or intended to be occupied by not more than one family and permitted roomers and boarders, as living accommodations, independent from any other family. A food preparation area within the room or rooms is evidence of the existence of a dwelling unit.

Environmental Impact Statement (EIS)

A document intended to provide impartial discussion of significant environmental impacts which may result from a proposed development project or problematic action. If the responsible official determines that a project or action may have a significant adverse effect upon the quality of the environment, the State Environmental Policy Act (SEPA) requires that an EIS be prepared. The purpose of the EIS document is to provide the government decision-makers with information to be considered prior to determining a project’s acceptability. The Draft EIS, which is circulated for review and comment, describes the action, analyzes the impacts of the action and proposes alternatives and mitigating measures. Comments on and revisions to the Draft EIS are included in the Final EIS, the findings of which are appealable.

Essential Public Facilities

A facility, conveyance or site that meets all of the following conditions: (1) the facility, conveyance, or site is used to provide services to the public; (2) these services are delivered by government agencies, private or non-profit organizations under contract to or with substantial funding from government agencies, or private firms or organizations subject to public service obligations; and (3) the facility, conveyance, or site is necessary to adequately provide a public service. Examples of essential public facilities include, but are not limited to, schools, water transmission lines, sewer collection lines, fire stations, hospitals, jails, prisons, highways and stormwater treatment plants.


See Floor Area Ratio (FAR).

Fixed-Route Service

Transportation service operated over a set route or network of routes, generally on a regular schedule.


The total area subject to inundation by the base flood. In Redmond, the base flood is the 100-year flood, the flood with a one percent chance of occurring in any given year.


Redmond administers two types of floodways. The zero-rise floodway is the channel of the stream and that portion of the adjoining floodplain which is necessary to contain and discharge the base flood flow without increasing the base flood elevation. The one-foot-rise floodway is the channel of the stream and that portion of the adjoining floodplain which is necessary to contain and discharge the base flood flow without increasing the base flood elevation more than one foot.

Floodway Fringe

The portion of the floodplain outside of the floodway which is generally covered by floodwaters during the base flood; it is generally associated with standing water rather than rapidly flowing water.

Floor Area Ratio (FAR)

A ratio which expresses the relationship between the amount of gross floor area permitted in a structure to the area of the lot on which the structure is located.

Forecasted Traffic Volume

Travel forecasting model output; the number of vehicles forecasted to travel on all or part of the future year street and highway network over a given period of time for a future year. Estimated volume also refers to modeled traffic, but for the current year or a previous year.

Functional Plan

A functional plan describes a City utility or department’s goals, mission, future projects and programs. City functional plans include: drainage, water, sewer and parks. These plans are developed with public input, consist of programs to implement City policies, and may be prepared for the entire City or portions of it. Functional plans help inform and support Citywide goals. Other local jurisdictions, such as the Lake Washington School District, also prepare functional plans.

General Fund

The general fund of the City or other government jurisdictions is used to account for all financial activities not reported in some other type of fund. It is used principally to account for the current operations of a jurisdiction’s general purpose department. Not included in the general fund are the activities included in capital projects funds, debt service funds, enterprise funds (i.e., funds for public utilities), internal service funds, and trust and agency funds.

General Obligation Debt

Local governments can raise revenue by selling tax-exempt municipal bonds and incurring debt. General obligation debt is secured by the full faith and credit of the City. There are two principal types of general obligation debt: (1) unlimited tax, which requires voter approval, and (2) limited tax or councilmanic debt, which can be issued without voter approval.


See Growth Management Act (GMA).

Gross Floor Area (GFA)

The number of square feet of total floor area bounded by the inside surface of the exterior wall of the structure as measured at the floor line.

Gross Site or Lot Area

The number of square feet of total property within a lot or other piece of property. Property not owned by the owner of the property or lot, such as public rights-of-way, are excluded.

Ground-Related Dwelling Unit

A dwelling unit with direct access to adjacent private ground-level open space.

Growth Management Act (GMA)

Refers to the 1990 State Growth Management Act (ESHB 2929) as amended, requiring urban counties and the cities within them to develop comprehensive plans to deal with growth in Washington State over the next 20 years. The GMA is codified at Chapter 36.70A RCW and other chapters.

Growth Management Planning Council (GMPC)

The body made-up of City and County representatives and created through an interlocal agreement by most of the cities in King County and the County to undertake interjurisdictional planning under the Growth Management Act or its successor.

High-Occupancy Vehicle (HOV)

Generally, a vehicle carrying more than one person, including a carpool, vanpool or bus.

High Resource Value

Type I, II or III wetlands; Class I, II and III streams; land or water that supports a Priority Species or habitat; land or water that is needed to maintain the functioning of an important environmental or ecological function, or land that is primarily made up of Class II and III agricultural soils.


A family, as defined by the Community Development Guide, living together in a single dwelling unit, with common access to and common use of all living and eating areas and all areas and facilities for the preparation and serving of food within the dwelling unit.

Housing Type

Classification of residences based on the number of dwelling units in a single structure. Examples are single-family detached; ground-related duplexes, triplexes and townhouses; and multi-family low-rise, mid-rise and high-rise apartments.

Housing Unit

A dwelling unit or group quarter.

Impact and Planning Area

The area for which the City of Redmond plans and in which development is likely to impact the City. The Impact and Planning Area is mapped in the Annexation and Intergovernmental Planning Element.

Impact Fees

A fee imposed on developers to help pay for the cost of providing public facilities needed to serve new development. Such charges reflect a desire to make new development pay for its impact on the community. The use of impact fees was authorized by the Growth Management Act.

Impervious Surface

A surface that cannot be easily penetrated. For instance, rain does not readily penetrate asphalt or concrete pavement.

Inclusionary Housing

Inclusionary housing is an affordable housing production mechanism which requires a specified number of affordable and/or low-income units within new housing developments. Inclusionary units are generally provided through density bonus incentives, requirements for cash contributions to a pool or minimum percentages of affordable units, or combinations of requirements and incentives.

Infill Development

Development consisting of either (1) construction on one or more lots in an area which is mostly developed, or (2) new construction between two existing structures.


The basic foundation of facilities and services, e.g., water, wastewater, power, streets and so on, which are necessary for urban development.

Intense Uses

Residential uses with a density of more than four units per acre, commercial uses, office uses and manufacturing uses.


More than one transportation mode or type of service.

Land Use

A term used to indicate the use of any piece of land. The way in which land is being used is the “land use.”

Level-of-Service (LOS)

A measure of a public facility or service’s operational characteristics used to gauge its performance.

Local Improvement District (LID)

A financing mechanism whereby specially benefited properties are assessed the costs of constructing public improvements.

Local Street

A street which provides for localized traffic circulation, access to nearby arterials and access to neighborhood land uses.

Low-Income Housing

Housing affordable to households with incomes between zero and 50 percent of area median income. See Moderate-Income Housing.

Manufactured Housing (also known as mobile homes)

Factory-built housing that meets standards established by the Federal Department of Housing and Urban Development and complies with the definition in WAC 296-150B-015(28) or its successor.


Means can and is used to express opportunity or permission. If a policy contains “may,” the decision-maker can undertake the action contemplated by the policy if, after reviewing the evidence, the decision-maker decides it is useful or desirable, and in keeping with this plan. “May” does not, however, confer any obligation on the decision-maker to undertake or allow the action. See also “Should” and “Shall.”

Minimum Density

A zoning method requiring that a certain percentage of the maximum density be provided on a subdivision or building site.


To reasonably reduce or eliminate the impact of development. See “Mitigation” for the definition of mitigation which applies to the sensitive areas regulations of the Community Development Guide.


The presence of more than one category of use in a structure; for example, a mixture of residential units and offices in the same building.

Mixed-Use Development

A project which combines more than one use, either in the same structure or in different structures located on the same site.

Mixed-Use Structure

A project which combines more than one use in the same structure; such as a building occupied by retail uses on the ground floor and housing on the floors above.


Types of transportation, such as walking, a bicycle, an automobile or a bus.


The statistical breakdown of travel by alternate modes, usually expressed as a percentage of travel by single-occupant automobile, carpool, transit, etc. Mode-choice goals are used to help people in the public and private sectors make appropriate land use and transportation decisions.

Moderate-Income Housing

Housing affordable to households with incomes between 50 and 80 percent of area median income.

Modular Housing

Factory-built housing conforming to the standards of the State of Washington building and energy codes (also known as “gold-seal” manufactured housing).

Multi-Family Use

A structure or portion of a structure containing two or more dwelling units.


Referring to accessibility by a variety of travel modes, typically pedestrian, bicycle, transit and automobile modes, but may also include water and air transport modes.

Neighborhood Plan

A land use policy statement applicable to a neighborhood adopted by the City Council and incorporated into the Neighborhoods Element of the Comprehensive Plan. Neighborhood plans are developed with extensive neighborhood involvement.

Non-Point Source Pollution

Pollution that enters water from dispersed and uncontrolled sources (such as surface runoff) rather than through pipes.

On-Site Retention

Permanent impounding of stormwater, or a large part of it, in man-made or man-modified lakes and ponds; often required for developments.

On-Street Parking

Parking spaces in the right-of-way.

Open Space

Any parcel or area of land or water essentially unimproved and set aside, dedicated, designated or reserved for public or private use.

Paratransit Service

Flexible transportation services which are operated publicly or privately, are distinct from conventional fixed-route, fixed-schedule transit, and can be operated on the existing highway and street system, generally with low capacity vehicles. Examples include vanpools, shared-ride taxis and demand-responsive services.

Park and Pool

A ridesharing arrangement in which individuals drive to a prearranged point to meet with others and travel together to their destinations in a carpool or vanpool.

Park and Ride Lot

A parking lot where transit or rideshare riders can leave their cars and ride a carpool, vanpool, bus or train to another location.

Peak Hour

One-hour interval within the peak period when travel demand is usually highest, e.g., 7:30 to 8:30 a.m. and 4:30 to 5:30 p.m.

Peak Period

Daily time periods when travel demand is usually highest, typically 6:00 to 9:00 a.m. and 3:30 to 6:30 p.m.

Pedestrian Amenities

Features of the built environment that improve the quality of foot or wheelchair travel, including ground floor retail uses in adjacent buildings, landscaped walkways, limited interference from automobiles, street furniture, etc.

Pedestrian Facility

An improvement designed to facilitate accessibility by foot or wheelchair, including sidewalks, curb ramps, crosswalks, overpasses and undercrossings, etc.


An area where the location and access to buildings, types of uses permitted on the street level, streetscape and storefront design are based on the needs of the customers on foot.

Permitted Use

A use that is allowed outright.

Planned Unit Developments (PUDs)

A planning technique which provides increased flexibility for the developer in exchange for a higher quality of development. Usually used for larger, multi-unit parcels, PUDs are characterized by a focus on overall project design rather than lot-by-lot zoning, setbacks and placement. Innovative housing types, open space and recreational facilities are often included. The process typically involves two-way communication between the developer and the community concerning design compatibility.

Point Source Pollution

A source of pollutants from a single point of conveyance such as a pipe. For example, the discharge pipe from a sewage treatment plant is a point source.


A contaminant that adversely alters the physical, chemical or biological properties of the environment. Pollutants can include solid waste, sewage, garbage, sewage sludge and municipal waste discharged into water.

Procedural Guidelines

Chapter 365-195 WAC. The Washington State Legislature charged the Department of Community Development with the task of adopting procedural criteria to assist counties and cities in adopting comprehensive plans and development regulations that meet the goals and requirements of the GMA. Along with listing requirements set forth in GMA, this document sets forth recommendations for meeting the requirements. It has been left up to each local jurisdiction to determine whether the recommendations are applicable.

Public and Semi-Public Uses

A use that is owned and operated by a public agency and characteristically operated by such an agency, or a use that is privately owned but has a character similar to a public use or which is traditionally considered to be a semi-public use. For example, a public school is a public use and a private school is a semi-public use.

Public Facility

Any use of land or physical structures, whether publicly or privately owned, for transportation, utilities, communication or for the benefit of the general public, including streets, schools, libraries, fire and police stations, municipal and County buildings, powerhouses, recreational centers, parks and cemeteries.

Public Service

A variety of services such as fire protection and suppression, law enforcement, public health, recreation, environmental protection, etc., available to the public and provided by government, substantially funded by government, contracted for or by government, or provided by private entities subject to public service obligation.

Puget Sound Air Pollution Control Agency (PSAPCA)

The lead agency for developing air quality standards for the Central Puget Sound Region in compliance with federal laws.

Puget Sound Regional Council (PSRC)

Formerly the Puget Sound Council of Governments, the PSRC is a regional planning and decision-making body for growth and transportation issues in King, Kitsap, Pierce and Snohomish Counties. Under federal transportation law, the Council is the Metropolitan Planning Organization (MPO), responsible for regional transportation planning and programming of federal transportation funds in the four counties. It is also the designated Regional Transportation Planning Organization (RTPO) for the four counties. PSRC manages the adopted regional growth strategy, VISION 2020.

Real Estate Excise Transfer (REET) Tax

A tax levied on the sale of real property. The amount of the tax is determined as a percentage of the sales price. The GMA authorized cities to impose a second 0.25 percent REET tax to be used to fund capital projects.

Residential Use

Any land use that provides for living space. Examples include artist studio/dwelling, boarding house, caretaker’s quarters, single-family, multi-family, special residence, floating home and mobile home park.

Response Time

The amount of time it takes fire and rescue officers or law enforcement officers to respond to calls for assistance.

Revenue Bond

A bond used to finance projects that produce revenue. The revenue from the project is used to make the principal and interest payments on the debt. Revenue bonds are used primarily by city utilities.


That portion of precipitation which flows over land surface and enters the stormwater system or streams or rivers during and following a storm.

Sensitive Areas

The following areas and ecosystems:

(a) Wetlands;

(b) Areas with a critical recharging effect on aquifers used for potable water;

(c) Fish and Wildlife Conservation Areas;

(d) Frequently Flooded Areas; and

(e) Geologically Hazardous Areas.

Critical areas are also known as sensitive areas.


See State Environmental Policy Act (SEPA).


Means obliged to. “Shall” is mandatory. If a policy contains “shall,” it is required that the decision-maker follow the policy where it applies. See also “May” and “Should.”


Means ought to. If a policy contains “should,” the decision-maker is to follow the policy where it applies unless the decision-maker finds a compelling reason against following the policy. See also “May” and “Shall.”

Significant Trees

A tree six inches or greater in diameter at breast height (dbh), in good health of a preferred species, of significant visual impact on the surrounding area or a landmark tree.

Single-Occupant Vehicle (SOV)

A vehicle carrying only one person.

Special Needs Housing

Housing that is provided for persons and their dependents who, by virtue of disability or other personal factors, face serious impediments to independent living and who require special assistance and services in their residence. Special needs housing may be on a permanent, long-term or transitional basis.

State Environmental Policy Act (SEPA)

Chapter 43.21C RCW. The State law passed in 1971 requiring State and local agencies to consider environmental impacts in the decision-making process. A determination of environmental significance must be made for all non-exempt projects or actions which require a permit, license or decision from a government agency. If the action does not have significant adverse environmental impacts, a Declaration of Non-Significance (DNS) is issued. If the action or project could have major impacts, an Environmental Impact Statement (EIS) is required.

Storm Drain

A system of gutters, pipes or ditches used to carry stormwater from surrounding lands to streams, lakes or rivers.


Water that is generated by rainfall and is often routed into drain systems in order to prevent flooding.


The visual character of a street as determined by elements such as structures, access, greenery, open space, view, etc.

Strip Commercial

Commercial or retail uses, usually one-story high and one-store deep, that front on a major street.

Structure, Detached

A structure which has no common or party wall with another structure.


The division of a parcel of land into two or more parcels. Subdivisions are classified into short subdivisions, also referred to as short plats, and long subdivisions, also referred to as long plats, based on the number of lots created. Redmond’s subdivision regulations are included the Community Development Guide.

Substantial Impacts

Effects or consequences of actions of such a nature or intensity that they will create an undesirable condition for uses or activities likely to take place in the area.

Substantial Improvements or Structures

Multi-family buildings, commercial buildings, office buildings, manufacturing buildings or structures, industrial buildings or structures, buildings and structures of a similar type and scale, and streets and utilities with a capacity to serve the listed types of uses. Substantial improvements or structures do not include single-family homes and accessory structures; agricultural buildings or improvements; buildings, structures or improvements typically associated with parks; or roads and facilities that typically serve the uses listed in this sentence.


The transportation of information using telecommunication technology such as teleconferencing, satellite television, facsimiles, cellular telephones and computer networking.


A form of ground-related housing where individual dwelling units are attached along at least one common wall to at least one other dwelling unit. Each dwelling unit occupies space from the ground to the roof and has direct access to private open space.

Traffic Counts

Number of vehicles observed as they pass by a manual count station or recorded as they cross an automatic counting device on a street or highway over a given time period. Intersection counts refer to the number of vehicles making each of the allowed movements through an intersection. Traffic counts taken on “typical” weekdays of “typical” months are part of the input data to which forecasted models are calibrated.

Transfer of Development Rights (TDRs)

A program in which the unused portion of a “sending” property’s zoned capacity – one of the separable rights of property – is sold to the developer of a “receiving” site, who is allowed to add the capacity to the zoned limit of that site. TDRs can be used to prevent the demolition of affordable housing units or to protect historically significant property or open space.


Public transportation; referring in this document to public bus, trolley and light rail, but not vanpools.

Transportation Demand Management (TDM)

Public and private programs to manage demand based on transportation supply. TDM measures are frequently directed toward increasing the use of public transportation, carpools and vanpools, and non-motorized travel modes.

Transportation Facility Plan (TFP)

A general plan that identifies and balances transportation capital expenditures and revenues for 10 to 15 years and demonstrates the viability of the Land Use Plan. The Transportation Facility Plan is part of the Transportation Element of the Comprehensive Plan.

Transportation Improvement Program (TIP)

A six-year funded program of transportation improvements. The TIP is updated and adopted annually.

Transportation Management Districts (TMD)

A TMD is an area for which transportation level-of-service standards and impact fees are set. A district is delineated by similar uses that generate similar trips.

Transportation Systems Management (TSM)

Making better use of the existing transportation system by using short-term, low-capital transportation improvements designed to improve the flow and/or safety of traffic operations.


The construction or relocation of electrical wires, telephone wires and similar facilities underground.

Urban Center

Defined in the Countywide Planning Policies as an area for focusing growth and aligning a high capacity transit system. To be designated an Urban Center, an area must have a land area between 0.5 and 1.5 square miles and must be able to support a minimum of 15,000 jobs at a minimum density of 50 jobs per gross acre and a minimum residential density of 15 households per acre.

Urban Growth Area

The area designated in the King County Comprehensive Plan for urban development and to be served with urban services, in addition to greenbelts, open space and other appropriate areas.

Urban Services/Urban Governmental Services

Includes those governmental services historically and typically delivered by cities and include storm and sanitary sewer systems, domestic water systems street cleaning services, fire and police protection services, public transit services and other public utilities associated with urban areas and normally not associated with rural areas.


An organized ridesharing arrangement in which a number of people (typically six to 15 people) travel together between fixed points on a regular basis in a van. Expenses are shared and there is usually a regular volunteer driver.

Vehicle Miles Traveled (VMT)

A measurement of forecasted travel demand; equivalent to one car, bus or truck traveling one mile.


The adopted regional growth strategy which describes linking high-density residential and employment centers throughout the region by high capacity transit, and promoting a multi-modal transportation system. VISION 2020 was adopted in 1990 by the predecessor to the PSRC.


The geographic region within which water drains into a particular river, stream or other body of water. A watershed includes hills, lowlands and the body of water into which the land drains.


Areas that are inundated or saturated by surface water or groundwater at a frequency and duration sufficient to support, and under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, bogs and similar areas. Wetlands do not include those artificial wetlands intentionally created from non-wetlands sites, including, but not limited to, irrigation and drainage ditches, grass-lined swales, canals, detention facilities, wastewater treatment facilities, farm ponds, landscape amenities or those wetlands created after July 1, 1990, that were unintentionally created as a result of the construction of a road, street or highway. Wetlands shall include those artificial wetlands intentionally created to mitigate the conversion of wetlands.

Wet Vault

A tank, usually underground, which has a designed volume of water storage. The vault allows sediment to settle out and oils to float to the surface, then the clean water from the middle flows out.

Work Trip

A trip that either starts or ends at the traveler’s place of employment.

Zero Lot Line Development

A development pattern of single-family houses constructed immediately adjacent to one side lot line (i.e., no side yard setback), coupled with an easement on the adjacent lot in order to maintain 10-foot separation between structures. This helps to preserve privacy and usable yard space, especially in small-lot areas.

Zone or Zoning District

A specifically delineated area or district in a municipality within which generally uniform regulations or requirements govern the use, size and development of land and buildings.


A type of development regulation that manages the use and development of land. Redmond’s zoning regulations are included the Community Development Guide.

Zoning Map

The official Zoning Map which classifies all land within the City with one of the zoning districts.

Ord. 1929; Ord. 1847