Description: This layer represents the septic tanks mapped to date.Contact: Fairfax County Health Department, Adrian Joye.Data Accessibility: Internal use onlyUpdate Frequency: Not complete, as neededInitial Creation Date: 11/15/2018
Description: This layer represents all of the private drinking, irrigation, and geothermal wells that have been mapped. Contact: Fairfax County Health Department, Adrian Joye.Data Accessibility: PublicUpdate Frequency: Not complete, as neededInitial Creation Date: 11/15/2018
Description: This layer represents the septic system drainfields that have been mapped to date.Contact: Fairfax County Health Department, Adrian Joye.Data Accessibility: Internal use onlyUpdate Frequency: Not complete, as neededInitial Creation Date: 11/15/2018
Description: This layer represents the geographic work area for the staff members in the Consumer Protection Program. It is based on the estimated caseload of hotel, restaurant, swimming pool, daycare, and campground inspections. This layer is redefined approximately every 2 years.Contact: Fairfax County Health Department, Adrian Joye.Data Accessibility: PublicUpdate Frequency: Approximately every 2 yearsInitial Creation Date: 11/15/2018
Description: This layer represents the geographic work area for the staff members in the Onsite Sewage and Water Program. It is used to assign inspection caseload for wells and septic systems. The layer boundaries are rarely modified, but the staff are rotated every 12-24 months.Contact: Health Department, Adrian JoyeData Accessibility: Publicly availableUpdate frequency: As neededCreation date: 11/15/2018
Description: Floodplain delineations were first added to the County tax maps in the 1970's for creeks and streams with watersheds of 1 square mile or greater. In 1977 all the studies on these large streams had been completed and a "Floodplain Overlay District" was created. Within several years this floodplain overlay district was depicted on the zoning maps. Again, these delineations were only for those creeks with drainage areas of over 1 square mile. A note in a 1981 memo to the Mapping Division about these delineations said, "...the County delineation of a Flood Plain Overlay District line on the tax map is treated here as a flag or general indicator of approximate location of this District's line. Normal development provides 2 field run topography professionally certified on which the floodplain elevations can be more accurately determined..." In 1985 the Zoning Ordinance was amended, an entire section on floodplains was added to Chapter 2 and the definition of what constituted a floodplain was significantly revised. Where as the Floodplain Overlay District had principally contained only those overbank areas inundated by the 100-yr storm along streams with drainage areas of 1 square mile or greater (i.e. 640 acres), the new definition included the overbank areas inundated by the 100-year storm along creeks with drainage areas of 70 acres and greater. But this change in the definition of floodplain created a problem for those who had become dependant on the tax maps to show them whether or not there was floodplain on a given property. These newly-defined floodplains were not yet studied or mapped and would only be mapped one property at a time, as each parcel containing these smaller floodplains submitted plans for development. When such parcels were developed, floodplain studies were required, and floodplain easements (later titled "floodplain and storm drainage easements") were recorded around these smaller floodplains. And as those easements were recorded, they were added to the tax maps. For all the floodplains which have been studied since 1985, the limits of the floodplain and storm drainage easements have been added to the tax maps, when such easements were required by the County Code or the Zoning Ordinance. But if a parcel has not yet been developed or if it was developed prior to 1985, there is usually no easement around the floodplain. There are also numerous cases where, for some reason, floodplain easements were recorded along small creeks with drainage areas well below 70 acres. These recorded "floodplain" easements were then added to the tax maps. THE RESULT: The tax maps cannot be used to definitively determine whether floodplain exists on a given parcel .There are approximately 900 miles of streams which meet the 70 acre drainage area requirement for floodplains, but to date (6/2003) almost 400 of these 900 miles remain unstudied. And if a stream has never been studied, no easement would have been recorded and thus the fact that it was a floodplain would not be reflected in the tax maps. Only after a determination of the drainage area is made can one know whether the overbank areas along a given creek meet the Zoning Ordinance definition of floodplain. Further if the drainage area is over 70 acres, only a floodplain study can determine the limits of the floodplain that is, how much of the overbank areas are inundated by the peak flow of the 100-yr storm. The layer for floodplains with drainage areas of over 1 square mile is good, but above that, it's inconsistent, especially in those areas which are minor floodplains (i.e. less than 360 acres of drainage area) and which were developed prior to 1985. The entire 850 or so miles of floodplain have not been mapped as unbroken corridors. And the "floodplain" here in Fairfax County, we're using the zoning ordinance definition which is the 100-yr water surface limits along streams with drainage areas of over 70 acres. This definition came into the zoning ordinance in 1985, so from that time, developers have had to study and map even these smaller floodplains on their developments and put them in easements. These easements have been captured on our tax maps since 1985, development by development, as the record plats were recorded. FEMA doesn't recognize as Special Flood Hazard Areas, many stream valleys that we would call floodplain. The layer currently on the data loader for floodplains is missing many segments of stream that are defined as floodplain per the zoning ordinance. Yet because of our zoning ordinance definition, this layer extends up in many areas far beyond where FEMA has mapped its 100-yr floodplains.Contact: Fairfax County GIS DivisionData Accessibility: Publicly availableUpdate frequency: DailyCreation date: 1/1/2000Layer name: GISMGR.FLOOD_PLAIN_RECORDEDDataset Name: GISMGR.ENCUMBRANCES
Copyright Text: The data set was created by Analytical Surveys Incorporated (ASI) and Landata under contract to Fairfax County. Quality control checks were performed by Engineering Systems Incorporated and Dewberry and Davis. Staff from the GIS branch were also used for quality control checking. Since 2001 Fairfax County staff have been solely responsible for maintaining this data.
Name: Resource Protection Areas (Chesapeake Bay Preservation Area)
Display Field: TYPE
Type: Feature Layer
Geometry Type: esriGeometryPolygon
Description: This set of data provides a delineation of Chesapeake Bay Preservation Areas (Resource Protection Areas and Resource Management Areas) as set forth in Section 118-1-7 of Chapter 118, Chesapeake Bay Preservation Ordinance, of the Code of the County of Fairfax, Virginia adopted by the Board of Supervisors on July 7, 2003 (effective November 18, 2003). The CBPA maps were adopted by the Board of Supervisors on November 17, 2003. Revisons to the 2003 RPAs were made based on a quality assurance field and map review. The revisions were adopted by the Board of Supervisors on July 11, 2005 (effective July 12, 2005). Where RPA and RMA boundaries on the adopted map differ from boundaries as determined from the text of the Ordinance, the text shall govern.
Description: The Fairfax County Stormwater Easement feature dataset includes two GIS feature classes, STW_EASEMENT_POLYGONS & STW_EASEMENT_COGOLINES. These feature classes were generated from extensive plat research to derive metes & bounds to then create all easements determined to be related to stormwater management. All easements are contained within the Fairfax County boundary. The project began in the Spring of 2005 and remains in production.
Copyright Text: Dataset created for the Maintenance & Stormwater Management Division by Spatial Systems Associates, Inc & Dewberry Team
Description: This data set contains a variety of easements that are captured from recorded subdivision plats and easement plats. Once a document has been recorded then the GIS office receives that document and creates any features that are shown on the recorded document. This layer contains the easement type by category and the name of the easement as stated on the plat. For newer easements there is also the deed book and deed page. This is used to perform research on the original document in the Courts system.This layers does not contain all easements. There are many easements before the GIS office started capturing all easements that did not get into the layer because they were not on the original mylars where this data was captured from. Also, in 2016 the GIS Division stopped capturing stormwater easements into this layer as there is different layer that contains the stormwater related easements.Contact: Fairfax County GIS DivisionData Accessibility: Publicly availableUpdate frequency: DailyLast Revision date: 1/1/2000Creation date: 1/1/2000Feautre Dataset Name: GISMGR.ENCUMBRANCESLayer name: GISMGR.EASEMENTS
Copyright Text: The data set was created by Analytical Surveys Incorporated (ASI) and Landata under contract to Fairfax County. Quality control checks were performed by Engineering Systems Incorporated and Dewberry and Davis. Staff from the GIS branch were also used for quality control checking. Since 2001 Fairfax County staff have been solely responsible for maintaining this data.
Description: The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual-chance flood event, and areas of minimal flood risk. The DFIRM Database is derived from Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). The file is georeferenced to earth's surface using the STATEPLANE projection and coordinate system. The specifications for the horizontal control of DFIRM data files are consistent with those required for mapping at a scale of 1:12,000.
Description: Estimated flood plain areas. Streams draining a watershed with a drainage area of greater than 70 acres but less than 360 acres (i.e. "minor floodplains") were buffered 100 feet on each side.A high-resolution Digital Elevation Model (DEM) of the county, created from over 1.1 million spot elevations, was used to create synthetic stream networks at 70ac a threshold. This synthetic stream network was then used to create a floodplain stream centerline for streams draining a watershed with a drainage area of greater than 70 acres but less than 360 acres (i.e. "minor floodplains"). The synthetic stream network was then used as the stream centerline to which the buffer was applied. Therefore, the gridded stream network was used to both locate the centerline against which the buffer was applied, and to determine the drainage area at any given point along a stream.
Description: The boundary lines for soils. The soil boundaries are for general planning purposes. Soils lines are not definitive. Soils gradually phase into one another. Characteristics of neighboring soils types will be found within a soil's borders. The code for the soil type is attributed to the area. This data must be included on all plans submitted for permits (site plans, grading plans, etc.) and must be used as the basis for whatever engineering tests are required before a construction permit can be issued.Contact: Northern Virginia Soil & Water Conservation DistrictData Accessibility: Publicly available Update frequency: As needed Creation date: 11/17/2015Layer name: NVSWDCMGR.SOIL_LINES
Copyright Text: Northern Virginia Soil & Water Conservation District
Description: Soils mapped over bedrock that may contain natural asbestos. Safety precautions must be taken during construction. Asbestos identification in map grid 49-3 may be incomplete: asbestos bedrock may be present in parcel bordering areas of mapped asbestos soil. For asbestos soils in Fairfax City, please contact the City of Fairfax. Orange soils, which overlie a majority of this geology, also contain shrinking-swelling clays which can cause foundation distress.Contact: Northern Virginia Soil & Water Conservation DistrictData Accessibility: Publicly available Update frequency: As needed Creation date: 11/17/2015Layer name: NVSWDCMGR.ASBESTOS_SOIL
Copyright Text: Northern Virginia Soil and Water Conservation District