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Spotsylvania County Home : Departments : Information Services : GIS/Mapping
History of GIS
at Spotsylvania County
The Spotsylvania County GIS Division, which is part of the Information Services Department, has been providing GIS services to the Spotsylvania County employees, citizens and businesses since 1993. The GIS Division is responsible for designing, developing, and maintaining the system and is staffed by a GIS Manager, a GIS Applications & Database Administrator, two (2) GIS Specialists, three (3) GIS Technicians, and up-to three (3) GIS Interns. The GIS Division receives about 50% of its funding from GIS Fees assessed for Site Plan Reviews, Record Plat Reviews and a variety of other mapping related services.
The county’s first venture into GIS began when the paper tax maps were converted into a digital format using a heads-up digitizing approach. At that time, the data was stored and maintained in an AutoCAD Computer Aided Drafting (CAD) format. Since then, as properties on the maps have been divided, surveyed, or changed hands, the digital tax parcels were updated using a coordinate geometry (COGO) technique. These newly created parcels were tied to survey points on plats, which created a highly accurate property fabric. Because of the extensive growth the county has realized over the past few years, much of the property has been surveyed and platted. However, in the rural areas of the county there has not been as much growth and subsequently the digital tax maps in that area were not updated and still reflect the positional accuracy anomalies inherited from the original paper maps. In numerous areas the non-updated, non-COGO’ed digital parcels do not accurately overlay the existing aerial imagery. This is a result of inaccuracies inherent in the mapping products, not by errors in the mapping process.
The base mapping layers were created from 1995 aerial imagery using a photogrammetric process. Some of the mapping features have been maintained over the years using information gleaned from site plans and property plats. However, many of the feature layers have not been maintained. The County is presently updating the planimetric base mapping layers again using a photogrammetric mapping process from aerial imagery flown in the spring of 2007 by the State of Virginia. The new mapping data and aerial imagery is expected to be available in early 2008.
The AutoCAD data was migrated into a GIS system in 2006. Presently the GIS Division maintains over 50 layers of spatial data that are managed using ESRI’s ArcSDE SQL Server Geodatabase product. The GIS Division performs most of the data capture and maintenance activities for the County. The Utilities Department has several employees skilled in GIS who are responsible for maintaining the water and wastewater layers. The GIS Division is presently hosting two ArcIMS web sites on its own County server. There is an Intranet site that is designed specifically for internal county employees and an external site that is available to the general public via the Internet: www.spotsylvania.va.us/GIS.
The GIS Division also provides data to the Sherriff’s Computer Aided Dispatch (CAD) and CrimeView analysis systems, and Fire, Rescue and Emergency Services’ FireView system.
The Information Services Department maintains an IBM AS400 mainframe that houses many of the County’s business systems. The GIS system is integrated with several of these business systems using an automated file transfer mechanism. The systems the GIS is integrated include:
- Real Estate System
- Business License System
- Utility Billing System
The County has standardized on SQL Server as a database engine for all new systems. The Information Services Department is presently implementing a CRW, Land Records Information System (LRIS) for our Community Development departments, which include Planning, Code Enforcement and Zoning/Inspections. In addition, the County’s NovaLIS, Computer Aided Mass Appraisal (CAMA) system, was developed on the SQL Server platform and is also integrated with the GIS using an automated file transfer mechanism.
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