Major GIS Projects
2004 Digital Aerial Photography
As a fundamental layer of the County geospatial framework, high-resolution imagery must be acquired on a regular schedule. The resulting imagery is used to update several other framework layers as features are built (houses, roads, etc.) or removed as features change. In the spring of 2004, the Sarpy County GIS Coalition entered into an interlocal agreement with the MAPA Aerial Photography Consortium for the acquisition of high-resolution digital aerial photography. This project is an on going effort that includes 17 government entities and is updated on a three year cycle. The new data will be delivered to Sarpy County in the spring of 2005 and will be available for sale through MAPA to the public. The final deliverables that Sarpy County will receive will be; Color & B/W 10” pixel resolution (whole county), 5” B/W for Urban areas (see map) and 2’ contours (whole county) created from LIDAR acquisition. Sarpy County is currently utilizing aerial photography from spring of 2001.
Survey Control Network
A network of survey monumentation is used to tie spatial data to a common coordinate system. Collectively, control monuments establish a network of precise locations to which mapped features can be referenced. As such, the monumentation network is a key base layer for the Sarpy County GIS program. The scope of the monumentation project included the development of a three mile geodetic control network. The control network is the basis for an ongoing section and quarter corner densification project. The monument data are now available through the Sarpy County survey office along with the Sarpy County scale factor data.
Cadastral Conversion Project
An accurate GIS parcel layer is a core component to any local government. In a world in which counties are increasingly expected to operate with speed and efficiency, a digital parcel layer is the basis for building the capacity to effectively create, maintain and distribute land information. This layer will be a key component in the county GIS and will be crucial aspect of a majority of county business in the future. In 2002, Sarpy County contracted Lamp, Rynearson and Associates to convert all county tax maps into a digital parcel layer. The basis for the data creation was the geodetic control network and all information was created by entering in the legal description (COGO) for the 50,000 parcels in Sarpy County. The final deliverables for the project include lots, Parcels, blocks, subdivisions, ROW, PLSS, hydrology, zoning, road centerlines, jurisdictions, city limits, county boundary, railroads and railroad ROW.
Internet Mapping Application
To facilitate the dissemination of Sarpy County's geographic data, an internet mapping application is being deployed for public use. The software will allow any internet user to view the county's GIS data from home or work. This application will be also be available in an expanded form through the new Sarpy County Premium Services.
In an effort to increase the accuracy of addresses within the county, Sarpy County is embarking on a County-wide address verification project. Sarpy staff is currently in the process of field verifying roughly 57,000 address points throughout the county. GPS technology is being utilized to map a point location for each address with in the County. This project will greatly enhance the Sarpy County E-911 systems and public information throughout the County.