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Permit and Resource Management Department Banner 750

Amended August 2, 2016

Unless the context clearly implies a contrary meaning or unless a rigid application of the definition would be contrary to the law, the following words, when utilized in this plan shall be construed as follows:

AASHTO Road Classification: A system of road classification based on the intended function of roads within the context of the overall road network. Arterial roads are intended to provide high capacity and mobility between cities, and other major population and job centers. Collectors connect local homes, job, and retail centers to the arterial network. Local roads serve individual homes, farms and businesses, and feed into the collector network. The road network functional hierarchy can be further refined by subdividing collectors and arterials into major and minor subclassifications.

There are slight differences in road geometry between rural and urban road classifications. The principal difference is the proportion of each class in the road network: Urban areas contain a relatively high number of arterials, whereas rural road networks have a fewer arterial and a relatively large number of collectors. In all classifications road width is flexible, and can be modified to suit local conditions, where necessary.

The following are road width standards for two lane roads unless otherwise noted: Rural Local Road: For roads with design speeds of less than 40 mph and volumes under 400 vehicles per day, the standard road width is 22 feet, with the exception of steep or hilly terrain, where the width may be reduced. Road width for maximum speed (60 mph) and volume (over 2000 vehicles per day) is 40 feet.

Rural Collector (Major or Minor):

For roads with design speeds of less than 40 mph and volumes under 250 vehicles per day, the standard road width is 22 feet. Road width for maximum speed (60 mph) and volume (over 2000 vehicles per day) is 40 feet.

Urban Collector (Major or Minor):

Standard width is the same as Rural Collectors, with additional allowances for bicycles, sidewalks, curbs, drainage, setbacks for public utilities, street lighting, and parking.

Rural Arterial (Major or Minor):

For roads with design speeds of less than 55 mph and volumes under 400 vehicles per day, the standard road width is 30 feet. Road width for maximum speed (75 mph) and volume (over 2000 vehicles per day) is 40 feet. Additional width is suggested if significant truck traffic is anticipated. Arterials are often multi-lane, and may be divided. Parking and individual driveways are discouraged.

Urban Arterial (Major or Minor):

For roads with design speeds of less than 45 mph, the standard road width is 30 feet. Standard road width for maximum speed (75 mph) and volume (over 2000 vehicles per day) is 40 feet. Additional width is suggested if significant truck traffic is anticipated Arterials are often multi-lane, and may be divided. On street parking and individual driveways are discouraged. Allowances should be made for sidewalks, curbs, drainage, setbacks for public utilities, and street lighting.  Where urban arterials intersect collectors or local roads, grade separations should be used when feasible.


Design speed is in excess of 55 mph. Access is limited and the road is grade separated at all intersections. Travel and breakdown lanes are 12 feet wide. Maximum grade is 6%, with less than 3% preferred. Design of bridges, culverts, walls, tunnels, other structures should be in accordance with current Caftans standards and AASHTO Standard Specification for Highway Bridges.

The following are horizontal road clearance standards: Rural Local Road: 7 feet clearance from the edge of the traveled way to unyielding objects such as trees, buildings, or other fixed objects that might severely damage an out of control vehicle. The benefits of removing obstructions should be weighed against environmental or aesthetic impacts.

Collectors (Rural and Urban):

10 feet clearance from the edge of the traveled way to unyielding objects such as trees, buildings, or other fixed objects that might severely damage an out of control vehicle. The benefits of removing obstructions should be weighed against environmental or aesthetic impacts.

Arterial (Rural and Urban):

Roadside should be clear and unobstructed as described in the AASHTO Roadside Design Guide. This standard involves detailed road specific calculations, but as a general rule, a clear zone of 20 feet is standard for roads with a 55 mph design speed.

Abut: To touch along a border or with a projecting part; to border on.

Accessory Building: A subordinate building, the use of which is incidental to that of the main building on the same lot or building site.

Accessory Renewable Energy System: An on-site renewable energy system, including but not limited to wind, bioenergy, solar, low-temperature geothermal heating systems, geothermal heat pump systems, and fuel cells and combinations thereof, where the energy generated is used primarily to meet the energy demands of the lawful use on the property where the system is located.

Adjacent: Having a common border.

Adjoin: Lie next to or in contact with.

Affordable Housing: Housing which costs no more than 30 percent of a low or very low income household's gross monthly income. For rental housing, the residents pay up to 30 percent of gross income on full-service rent (including utilities) or the combination of rent and separate utility costs. For home ownership, residents pay up to 30 percent on the combination of mortgage payments, taxes, insurance, and utility costs.

Agricultural Area: See agricultural production area.

Agricultural Employee Housing: See Farmworker Housing

Agricultural Land: Land designated within an agricultural land use category.

Agricultural Operation: A specific agricultural use or business.

Agricultural Production Activities: Those activities directly associated with agriculture, but not including agricultural support services, processing, and visitor serving uses. Activities include growing, harvesting, crop storage, milking, etc.

Agricultural Production Area: Land used to produce food, fiber, or plant materials and its immediate surrounding area.

Agricultural Support Services: Processing services, maintenance and repair of farm machinery and equipment, veterinary clinics, custom farming services, agricultural waste handling and disposal services, and other similar services.

Agriculture: The production of food, fiber, plant materials, and the raising and maintaining of horses, donkeys, mules, and similar livestock and farm animals.

Air Taxi: Aircraft operated by a company or individual that performs air transportation on a non-scheduled basis over unspecified routes usually with light aircraft.

Air Taxi Operator:    An operator certificated in accordance with FAR Part 135 and authorized to provide, on demand, public transportation of persons and property by aircraft. Generally operates small aircraft "for hire" for specific trips.

Alternative Septic System: Engineered septic and leach field systems that Sonoma County has been authorized to permit on a routine basis. Currently these include Filled Land, Shallow Sloping, Pressure Distribution and Mound septic systems. The Filled Land and Shallow Sloping systems are similar to Standard Septic System servicing requirements, while Mound and Pressure Distribution Systems require quarterly monitoring, an easement allowing the County to conduct annual monitoring of these systems, and an annual operating permit.

Alternative Sewage Disposal System: A non-standard sewage disposal system that has demonstrated satisfactory operation, maintenance, and monitoring under Phase I and Phase II of the Non-standard Sewage disposal Program and approved by the County.

Alternative Transportation Mode: Low impact, non polluting vehicles intended for personal mobility.  Electric scooters are an example of an alternative transportation mode.

Ancillary Use: A use related to and subordinate to the primary use of the land.

Animal Husbandry: The raising, breeding, and maintaining of horses, donkeys, mules, and similar livestock and farm animals.

Annual Operations: Annual operations are the number of aircraft takeoffs plus the number of aircraft landings occurring during a twelve month period.

Annual Passengers: Annual passengers are the total number of scheduled and commuter air passengers enplaning (boarding a departing aircraft) and deplaning (exiting an arriving aircraft) at an airport during a twelve month period.

Aquaculture: The raising of fish or produce in water.

Aquifer: A geologic formation that stores, transmits, and yields significant quantities of water into wells and springs.

Area of Interest: An area of land surrounding a city but outside of its sphere of influence, within which the city has expressed a desire to review land use.

Area Plan: A planning document which sets forth policies and programs which regulate development in a local area at a greater level of detail than the general plan.

Arterial: Medium to high capacity roadway serving primarily through traffic.

Assessment District: A district formed through special procedures for the purpose of taxing itself for certain benefits or improvements.

Avigation Easement: An interest in real property frequently obtained by airport owners as a means of safeguarding airport activities. Such an easement may create a right for free and unobstructed passage of aircraft over the property above a specified altitude and a right to subject the property to noise, vibration, fumes, and other effects associated with normal airport activity.

Base Zone: As used in the Sonoma County General Plan, a zoning district which describes and regulates the predominant use of the land.

Bay Area Traffic Operations System: An integrated information and dispatch system operated by Caftans and the CHP. The system includes roadway embedded traffic detectors, closed-circuit video, tow truck dispatch and message signs and broadcasts that alert drivers and transit riders to conditions.

Bikeway: Any facility that explicitly provides for bicycle travel.  Bikeways are classified into three types denoting a degree of separation from the highway, as follows: Class 1 (completely separated right-of-way designated for the exclusive use of bicycles), Class II ( a restricted right- of-way designated for the exclusive or semi exclusive use of bicycles), and Class III ( a shared right-of-way designated by signing or stenciling on pavement).

Biosolids: Sewage sludge that has been treated, tested and shown to be capable of being used beneficially as a soil amendment for agricultural, silvicultural, horticultural, and land reclamation activities.

Biotic: Relating to plant and animal life.

Biotic Resource Area: Unique or significant plant or animal communities, including estuaries, fresh and salt water marshes, tideland resources, riparian corridors and certain terrestrial communities.

Building Envelope: A defined location or locations on a parcel.

Build out: A theoretical level of development which assumes that every parcel of land will develop to the maximum allowed by a plan or zoning.

Channelization: The straightening and/or deepening of a water course for purposes of stream runoff control or ease of navigation. Channelization often includes the lining of stream banks with retaining material such as concrete.

Circulation: The movement of goods and people within a region.

Clearcutting: A method of timber harvest as defined by the California Department of Forestry and Fire Protection.

Clustered Development: Development in which a number of dwelling units are placed in closer proximity than usual, or are attached, with the purpose of retaining an expanse of undeveloped or less developed land.

Collector: A relatively low speed, low volume roadway which provides circulation within and between neighborhoods which is intended to collect trips from local streets and distribute them to the arterial network.

Combining District: A zoning designation which is superimposed over a base zoning district to modify the regulations in the base zoning district.

Commercial Renewable Energy Facility: An energy generation facility using renewable fuel sources, including but not limited to wind, bioenergy, solar, geothermal, and fuel cells and combinations thereof, where the energy generated is used to meet off-site energy needs.

Community Noise Exposure Level (CNEL): CNEL is a measure of the cumulative effect of individual noise events averaged over a 24 hour period and weighted by the time of occurrence.

Community Opportunity Areas:  Areas or communities in the County which are relatively low income and that are or may be underserved by public services and infrastructure. They include “disadvantaged unincorporated communities” under Senate Bill 244, which was passed in 2011 and amended California Government Code Section 56430 (Cortese-Knox-Hertzberg Act) and California Government Code Section 65302.10 (Updating Elements of the General Plan).

Community Separator: Rural open space and agricultural and resource lands around cities and unincorporated communities that maintain community identities, prevent sprawl, protect natural resources, and provide visual separation between cities and unincorporated communities. Community Separators are designated on the maps in the Open Space and Resource Conservation Element.

Commuter Carrier: An air taxi operator which provides service to the general public and performs at least five round trips per week between two or more points and publishes flight schedules which specify the times, days of the week and places between which such flights are performed. Commuter carriers engaging in regularly scheduled passenger service to the public with aircraft with seating between 10 and 60 seats are treated as regional carriers for purposes

of applying the scheduled air carrier service departure allocations established in the ATE.

Compatible, Congenial, Harmonious with: As used in the land use and other elements, referring to land uses and types of development that can exist together without creating a conflict.

Conservation: The management of natural resources to prevent waste, depletion, destruction, or neglect.

Constraints: Impediments to development, such as slope instability, lack of adequate water.

Conventional Wastewater Treatment Plant: A wastewater treatment facility producing secondary or tertiary-treated effluent that is constructed on the site where it is located. Typically it receives and treats wastewater either from an agricultural processing facility on the same parcel or from multiple parcels or land uses. In the latter case, the facility is typically owned and operated by a public agency, including sanitation districts and zones, and is built to service large to very large wastewater flows. Due to their size, treated effluent is typically discharged to the surface. Maintenance is required on a daily basis, each plant must have an operating permit approved by the Regional Water Quality Control Boards and operators must be licensed by the State of California.

Countywide: Sonoma County in its entirety; both the unincorporated areas and the Cities.

Cultivation: The act of preparing the soil for the raising of crops.

Density: As generally used in the land use element, the term refers to the number of dwelling units per acre or the number of acres per residential dwelling unit.

Discretionary Project or Permit: A project or permit which the decision making body may approve, approve with conditions or deny.

Dwelling Unit: A residence containing cooking, sleeping and sanitation facilities used to house the members of a household. Within the meaning of the General Plan, dwelling unit does not include a second dwelling as defined in the Sonoma County Code Section 26-10, nor to Farmworker and Farm Family Housing.

Dynamic Analysis. An elastic (as opposed to static) analysis of the response of a structure to earthquake forces, wherein the maximum movement in all dimensions of all components of the structure are used to calculate an approximate total response of the structure.

Easement: Usually the right to use property owned by another for specific purposes.

Easement; Conservation, Scenic, or Open Space: An interest in real property whereby open space is secured.

Economically Practical: That which is capable of being accomplished in relation to a proposed program, land use or development such that the costs associated therewith do not make the proposed land use or development infeasible.

Economically Viable: That which is capable of making a reasonable return on investment.

Emergency Service: Emergency services conducted by public agencies or private firms including the following:

  1. fire services including wildland fire suppression
  2. police services
  3. medical services

Environment: The circumstances, objects, or conditions by which one is surrounded. The physical conditions including both natural and man made, which exist within an area including land, air, water, minerals, flora, fauna, noise, and objects of historic or aesthetic significance.

Environmentally Suitable: Having minimal or insignificant adverse impact on the environment.

Environmental Review: The identification and analysis of the potential adverse impacts of a proposed development on the environment conducted pursuant to the California Environmental Quality Act (Public Resources Code 21000 et seq); the California Environmental Quality Act Guidelines (Title 14, California Administrative Code Section 15000 et seq); and Sonoma County Code Section 23A-1 et seq.

Erosion: The loosening and transportation of rock and soil debris by wind, rain, or other running water or the gradual wearing away of the upper layers of the earth.

Estuary: The lower course of a river or stream where tidal influence is noticeable; the mixing zone of fresh and salt waters near the mouth of a river or stream.

Exaction: A contribution or payment required as an authorized precondition for receiving a development permit or offered as mitigation.

Experimental Septic System: New technology septic systems that Sonoma County has been authorized to permit in limited numbers and under conditions specified by the Regional Water Quality Control Boards.

Experimental Sewage Disposal System: Any on site sewage disposal system, other than standard leachline or Alternative Sewage Disposal Systems, which has been developed,

researched and monitored by a major research land grant university or equivalent and approved by the County.

Farmworker Housing: A dwelling unit or dwelling units occupied by persons employed by agricultural operations, and their dependents.

Feasible: See Practical.

Federal Aviation Regulation: Regulations published by the Federal Aviation Administration denoting specific Federal requirements in the certification and operation of aircraft, airmen and airports.

Fill: A deposit or earth material placed by artificial means; any act by which earth, sand, gravel, rock, or any other material is placed, pushed, dumped, pulled, transported, or moved to a new location above the natural surface of the ground or on top of the stripped surface.

Flight: Refers to an aircraft operation - either a departure or an arrival.

Flood, 100 year: The magnitude of a flood expected to occur on the average every 100 years, based on historical data.  The 100 year flood has a 1/100, or one percent, chance of occurring in any given year.

Flood Control: Measures that are taken to increase the hydrologic capacity of a natural water course or to create new man-made channels or reservoirs to drain and contain precipitation that otherwise exceeds the capacity of the water course, in an effort to reduce flood damage, usually to man made improvements.

Flood Plain: The land area adjacent to a watercourse, drainage way, or creek which has been or may be covered by floodwaters. The boundaries of a flood plain are typically described in terms of the magnitude of a flood event such as the "100 year flood plain".

Floodway: The portion of a stream channel and the adjacent flood plain that must be reserved in order to discharge the 100 year flood without cumulatively increasing the water surface more than one foot. The Flood Insurance Rate Maps show floodway boundaries for those streams studied as part of that program.

Freeway Service Patrol: A joint program provided by Caftans, the California Highway Patrol and the local transportation agency. The FSP program is a free service of privately owned tow trucks that patrol designated routes on congested urban California freeways. FSP operates Monday through Friday during peak commute hours, and all day in pre-designated freeway construction zones.

Freight Hub: A facility for consolidation and transfer of freight from one mode to another, and/or distribution of bulk freight to local carriers.

General Aviation: General aviation includes all aviation activity except activity by airlines and the military. The privately owned aircraft is the most common type of general aviation aircraft and activities include:

  1. personal and business travel
  2. flight instruction and training
  3. recreational flying
  4. commercial uses (eg. aerial application fire fighting, photography, mapping, air taxi, and emergency services)

General aviation aircraft includes airplanes, helicopters, ultralights and specialty craft (eg. blimps, balloons, and hang-gliders)

Goal: A general statement of a desired end toward which an effort will be directed.

Habitat Connectivity Corridors: Linkages needed to allow movement of wildlife across the landscape that are designated on Figures OSRC-5a through OSRC-5i.

Headway: The time interval between transit vehicles, such as trains busses or ferries, moving in the same direction on a particular route.

Heritage Road: A public road with unique scenic, historic, recreational, cultural, archeological and/or natural qualities that may be compromised if the road is fully improved to meet current road standards.

High Public Occupancy. A building or structure with an occupant load of 300 or more persons, as determined by the occupant load calculation in the current adopted California Building Code.

Highest Feasible Safety Standard. Standards in the current adopted California Building Code, including local amendments.

Holding Capacity (also, Residential Holding Capacity): See "Build Out".

Household: The year round occupants of a dwelling unit.

Implementation: Actions, procedures, programs, or techniques that carry out policies.

Incidental: See "Ancillary"

Incidental Sales: Sales of goods and products that are accessory and subordinate to the primary use of a property and conducted so as not to significantly change the character, appearance, or operation of the primary use.

Indicators: Quantifiable parameters and representative measurements of demographic, economic, social, environmental, and other conditions related to the quality of life and the effectiveness of General Plan goals, objectives, and policies.

Infill Development: Development of vacant or under used land (usually individual lots or left- over properties) within areas which are already largely developed.

Infrastructure: Public services and facilities, such as sewage disposal systems, other utility systems, and roads.  Generally refers to physical improvements as opposed to social services.

Known Geothermal Resource Area (KGRA): Federal designation of boundaries describing an area with known geothermal potential.

Land Use: The occupation or utilization of land or water area for any human activity or purpose.

Lead Agency: Means the public agency which has the principal responsibility for carrying out or approving a project.

Local Agency Formation Commission (LAFCO): A County commission that reviews and evaluates all proposals for the formation of special districts, incorporation of cities, annexation to special districts or cities, consolidation of districts, merger of districts with cities, and setting of spheres of influence. Each county's LAFCO is empowered to approve, disapprove, or conditionally approve these proposals.

Local Area: Any of the unincorporated communities within the County or a geographic area, such as a valley, that is lesser in area than the planning area in which it is located.

Local Area Development Policies: Policies that apply to a local area, as a sub unit of a planning area, and which provide a greater level of detail or relate special circumstances for specific use or development in a local area.

Lot: See parcel.

Lot Size, Minimum: The smallest size parcel which is permitted to be created if a lot can be subdivided.

Lower-income Housing: Housing affordable to lower income households as defined in Section 50079.5 of the Health and Safety Code, as that section may be amended from time to time.

Mainline Carrier: Mainline carriers engage in regularly scheduled air carrier passenger service using jet aircraft with approximately 100 to 150 seats.

Major Employment Center: An area that is exclusively industrial and/or commercial with a total employment of 500 persons or more.

Major Subdivision: The division of any parcel or parcels of improved or unimproved land into five (5) or more parcels, pursuant to the provisions of the Subdivision Map Act (Government Code 66410 et seq) and the Subdivision Ordinance (Sonoma County Code, Chapter 25).

Maximum Single-event Noise Level (Lmax): Lmax is a measure that indicates the maximum noise level reached during a single aircraft overflight, expressed in dBA, at a specified point of measurement.

Minor Subdivision: The division of any parcel or parcels of improved or unimproved land into four (4) or fewer parcels, pursuant to the provisions of the Subdivision Map Act (Government Code 66410 et seq) and the Subdivision Ordinance (Sonoma County Code, Chapter 25).

Mitigate: To ameliorate, alleviate, or avoid to the extent  reasonably feasible.

Mitigation Measure: An action or series of actions designed to avoid or lessen the extent of an adverse impact of a project, pursuant to the provisions of the California Environmental Quality Act Guidelines (14 Cal. Adm. Code Sec 15370).

Natural Resource: Something (as a mineral, waterpower source, forest, or kind of animal) that occurs in nature.

Navigable Stream: A stream of sufficient capacity to be used for commercial or recreational purposes and/or capable of being navigated by oar or motor propelled small craft.

Non Conforming Use: A lawful use existing on the effective date of a zoning ordinance restriction and continuing since that date in nonconformance to the restriction.

Objective: A specific detailed statement of a desired future condition toward which the County is committed and progress is measurable.

Open Space: Any parcel or area of land or water which is essentially unimproved and devoted to an open space use as defined in Section 65560(b) of the Government Code.

Package Wastewater Treatment Plant: A wastewater treatment facility producing secondary or tertiary treated effluent that is manufactured off site in modular fashion and delivered in “packages” (truckloads) to be installed at a particular location. They may be ordered in different sizes and may be connected together to achieve treatment of fairly large

wastewater flows. They may dispose of treated effluent using either subsurface or above ground discharge, and must have an operating permit approved by the Regional Water Quality Control Boards and the applicable license for treatment plant operation acceptable to PRMD.

Parcel: A legally defined lot, or contiguous group of lots, in single ownership or under single control, usually considered a unit for purposes of development.  (See "lot").

Peak Hour: For any given roadway, the daily 60 minute period during which traffic volume is highest.

Performance Standards: Standards or criteria for regulating or determining the acceptability of certain land uses based upon the performance of the use.

Permitted Use: A typical land use that is allowed within a particular General Plan Land Use category. A permitted use is considered to be consistent with and to further the objectives of the General Plan. Such a use may also be subject to performance or other development standards and either ministerial or discretionary approval in the zoning ordinance.

Places of Public Assembly: Meeting halls, schools, hospitals, and other associated medical facilities, mosques, temples, or other places of religious worship.

Planning Areas: Nine (9) geographic subunits of the County.

Policy: Specific statement that guides decision making in order to achieve a goal or objective.

Practical: That which is capable of being accomplished in a successful manner within a reasonable period of time, taking into account economic, environmental, social, legal and technological factors.

Preservation: Restoration or protection from deterioration of features having environmental, cultural, historic, or other resource value.

Primary or Predominant Use: The prevailing use of the land.

Prime Soils: Soils classified by the United States Department of Agriculture Soil Conservation Service as Class I or Class II.

Productive Agricultural Land: Land currently used or capable of being used for the production of food, fiber or plant materials.

Prominent Hills: Highly visible hills or steep terrain that are a conspicuous component of the landscape.

Public Services: Infrastructure, including roads, sanitary sewers, storm drains and water mains and social services, including police, fire, health, schools, transit, recreation and libraries. Public Utility Facility: A facility for the provision of water, light, heat, communications, power, or for sewage collection, treatment, or disposal.

Public Use Airport: A publicly or privately owned airport where public use is invited or allowed without restriction, as defined by the State Division of Aeronautics; such airports must have a California Airport Permit issued by the Division.

Public Water Supplier: One of the following types of entities:

  1. Sonoma County Water Agency.
  2. Incorporated Cities.
  3. The following suppliers for Urban Service Areas: Bodega Bay Public Utility District

Sea Ranch Water System Occidental Community Services District Geyserville Water Works Forestville County Water District Sweetwater Springs County Water District California American Water Company Penngrove Water Company Valley of the Moon Water District

  1. The following County-operated community systems:

Sonoma County Service Area 41 - Fitch Mountain Sonoma County Service Area 41 - Freestone Sonoma County Service Area 41 - Jenner Sonoma County Service Area 41 - Salmon Creek Sonoma Mountain County Water District Timber Cove County Water District

  1. The following other community systems serving more than 500 year-round residents: Camp Meeker Recreation and Park District

Kenwood Village Water Company Russian River County Water System

  1. Any new public water suppliers which meet any of the following criteria:

Incorporated cities. Suppliers for urban service areas. County-operated community systems. Community systems serving more than 500 year-round residents.

Public Water System: A connected system of pipelines, pumps, valves, treatment plants, storage tanks, reservoirs and related facilities providing water to multiple users.

Recycled Water: Water which, as a result of treatment of waste, is suitable for a direct beneficial use or a controlled use that would not otherwise occur and is therefore considered a valuable resource.

Redevelopment Project: An activity undertaken by a Redevelopment Agency set up under State law to revitalize blighted areas as defined by the Health and Safety Code.

Regional Carrier: Regional carriers engage in regularly scheduled air carrier passenger service between mainly small and medium sized communities and the nation’s large airports, using turbo-prop aircraft with seating between 10 to 78 seats and small jets with 99 or fewer seats. Commuter carriers engaging in regularly scheduled passenger air carrier service to the public are treated as regional carriers for purposes of applying the scheduled air carrier service departure allocations established in the ATE.

Responsible Agency: As defined by the State CEQA guidelines, the term Responsible Agency includes all public agencies other than the lead agency which have discretionary approval power over a project.

Ridgeline: A line connecting the highest points along a ridge, and separating drainage basins or small scale drainage systems from one another.

Right of Way: The strip of land required to build certain transportation and public use facilities, such as roadways, railways, and public utility lines.

Riparian: Associated with or dependent upon a river, stream or other water body.

Riparian Corridor: In general, the area occupied by rivers or streams and related plant and animal communities. As used in the Open Space and Resource Conservation Element, the areas occupied by rivers or streams designated on Figures OSRC-5a through OSRC-5i and related plant and animal communities.

Riparian Functions: The beneficial uses of areas in and along streams, including: providing food, water, and breeding, egg deposition and nesting areas for fish, amphibians, reptiles, birds, insects, and mammals; providing protective cover, shade and woody debris to stream channels as habitat for coho salmon, steelhead, freshwater shrimp, and other protected and common aquatic-dependent species; providing movement opportunities, protective cover, and breeding, roosting, and resting habitat for terrestrial wildlife; filtering sediment and pollutants in runoff into streams; providing erosion protection for stream banks; and facilitating groundwater recharge.

Rural: A comprehensive term contrasting to urban. Those areas not intended for urban development.

Scenic Corridor: As designated on Figure OSRC-1 and Figures OSRC-5a through OSRC-5i of the Open Space and Resource Conservation Element, a strip of land of high visual quality along a certain roadway.

Scenic Highway: Those roadways in Sonoma County that have been so designated by the State of California.

Scenic Landscape Unit: A landscape of special scenic importance in Sonoma County which provides important visual relief from urban densities.

Scheduled Air Carrier Services: Scheduled air carrier services are defined to consist of two components, regional carriers and mainline carriers.

Secondary Use: As used in the General Plan land use categories, a use permitted within a special land use category based on its compatibility with the primary or predominant use therein.

Septic System: A sewage treatment system that includes a settling tank through which liquid sewage flows and in which solid sewage settles and is decomposed by bacteria in the presence of oxygen. Septic systems are often used for individual home waste disposal where an urban sewer system is not available.

Setbacks: The distance a building or use must be withdrawn from a road right-of-way, watercourse, parcel boundary or other designated feature .

Side Friction: The movement of vehicles outside of the main flow of traffic which may interrupt the efficient flow of traffic such as parking and entering or leaving driveways.

Significant and/or Substantial: Important, weighty, distinctive.

Silviculture: A branch of forestry dealing with the development and care of forests.

Single-Event Noise Exposure Level (SENEL): SENEL is a measure of the noise generated by a single aircraft overflight. It includes the loudness of the event during the time interval that the event is above the threshold level.

Single Room Occupancy Units: A cluster of residential units, each unit being substantially smaller in size than a typical apartment unit, within a residential hotel, motel, or similar facility providing sleeping or living facilities in which sanitary and kitchen facilities may be either shared within the project or provided in each unit.  Single Room Occupancy Units are for the purpose of providing affordable housing, and not for the purpose of serving recreational or travel needs.

Smart Growth: Development that is environmentally sensitive, economically viable, community-oriented, and sustainable. These goals are reached through planning that incorporates the following principles:

  1. Encourage infill development of urbanized communities
  2. Create range of housing opportunities and choices
  3. Encourage compact building design
  4. Protect agriculture and open space
  5. Create walkable neighborhoods
  6. Enable choice in transportation modes that are integrated and consistent with land use objectives
  7. Create fair and equitable rules for development

Sound Mitigating Structure: A barrier, berm, structure, or other physical feature installed to reduce noise from transportation facilities, development projects, and/or other noise sources, particularly as it affects residences and other noise sensitive uses.

Special Districts: Districts established under State law and through LAFCO in order to provide special services, such as water and sewer, street lighting and other services, to the residents within the boundaries of the district.

Specific Plan: Consistent with the State of California Government Code Section 65450 et. seq, a specific plan is a tool for detailed design and implementation of a defined portion of the area covered by a general plan. A specific plan may include all detailed regulations, conditions, design standards, programs, financing mechanisms and/or proposed legislation which may be necessary or convenient for the systematic implementation of any general plan element(s).

Specimen Tree: Means a tree which has departed in some respect from the standard characteristic of the species and has developed a character of shape, size, or branch structure that gives it special interest.

Sphere of Influence: The probable ultimate physical limits and service area of a local government jurisdiction as determined by LAFCO.

Standard Septic System: A wastewater treatment system consisting of a properly sized septic tank that discharges to a properly sized subsurface leach field that meets all required setbacks to groundwater, water wells, road cuts, surface waters and structures. These systems typically require that the septic tank be serviced every second or third year.

Super Williamson Act: Similar to the Williamson Act, 1998 State legislation (as it may be amended from time to time) that created “Farmland Security Zones” where the commitment to agricultural use is for a longer period and the property tax benefits are greater than under Williamson Act.

Sustainability: That which meets our current needs without compromising the ability of future generations to meet their needs.

Sustainable yield: The amount of water that can be used over the long term without exceeding the replenishment rates over time or causing long term declines in available surface or groundwater resources.

Telecommunication Facility: Facility that sends and/or receives electromagnetic signals, including antennas and towers to support receiving and/or transmitting devices along with accessory structures, and the land on which they are all situated.

Traffic Analysis Zones: A statistical geographical unit for information related to traffic generation and transportation modeling.

Traffic Calming: A combination of alterations and improvements to the road network intended to reduce the negative effects of motor vehicle use, alter driver behavior and improve conditions for non-motorized street users. The purpose of traffic calming is to reduce the speed and volume of traffic to acceptable levels for the functional class of a street and the nature of existing uses along the street in order to improve traffic safety and preserve community character.

Transit: The conveyance of persons from one place to another on a public transportation system.

Transit Center: An area that is designed for several bus and/or rail routes. Transit centers will usually have multiple passenger facilities, such as shelters and benches, and also will usually have some form of information available for the passengers, this may include a staffed information center where passengers can buy passes and get printed schedules.

Transmission line: A conductor for transmitting electrical or optical signals or electric power such as a cable or power line.

Transportation: The conveyance of goods and people from one place to another.

Transportation Demand Management (Federal Highway Administration) or Traffic Demand Management (Caftans): Programs and strategies that reduce congestion through reduction of demand, rather than increasing capacity or supply.  The goal of TDM is to reduce the number of vehicles using highway facilities while providing a wide variety of mobility options for those who wish to travel.  Examples of TDM are:

  1. High occupancy vehicle lane
  2. Alternative work hours
  3. Ride sharing programs
  4. Telecommuting
  5. Land use policies that reduce distance between jobs and housing.

Transportation Stores: Facilities located in major job and retail centers that provide information and services such as transit passes, rideshare matching, vanpool subscriptions, etc.

Transportation Noise: Sound due to traffic on public roadways, waterways, railroads, and airports.”

Unincorporated Community: Areas within the County's jurisdiction that have some or all urban services that support urban level densities.

Urban: Contrasting with rural, pertaining to uses of land typically occurring within cities, such as high density residential, commercial, and industrial uses.

Urban Development: Development occurring within urban land use categories (urban residential, commercial, industrial and public/quasi public categories within Urban Service Areas).

Urban Expansion Area: The land located between the existing city limits and the urban service boundary.

Urban Fringe: An area adjacent to or in proximity to and outside of an urban service boundary.

Urban Growth Boundary: A voter designated limit to the urban development of a city.

Urban Service Area: The geographical area within the Urban Service Boundary that is designated for urban development on Figures LU-2a through LU-2i of the Land Use Element.

Urban Services: The full range of public services and infrastructures including sewer, water, police and fire protection, roads and transit etc.

Urban Service Boundary: A designated limit to the urban development of the cities and unincorporated communities of the County.

Vegetation Removal: The cutting, breaking, burning or uprooting of vegetation or the application of herbicide to vegetation, or the covering over of vegetation with earth or the compacting of the soil under, around or over said vegetation. For the purposes of this definition, vegetation means all natural, non cultivated growth of plant life including the root system, the stem, trunk, crown or branches or leaves or blades.

Vehicle Miles of Travel (VMT): A unit to measure vehicle travel made by a private vehicle, such as an automobile, van, pickup truck, or motorcycle. Each mile traveled is counted as one vehicle mile regardless of the number of persons in the vehicle.

Viable: Capable of success or continued effectiveness. For land uses, having the apparent physical characteristics necessary to accomplish the use.

Viewshed: The area visible from a defined observation point.

Water User: A person or entity whose diversion, appropriation, extraction, acquisition, storage or usage of water meets all applicable legal requirements.

Williamson Act: The California Land Conservation Act of 1965 (as it may be amended from time to time) that allows Counties to establish agricultural preserves through agreements with property owners to maintain agricultural uses in exchange for property tax benefits.

Zoning District: A designated section of the County for which prescribed land use requirements and building and development standards are uniform.