Preservation & Long-Term Access to Geospatial Data
The preservation of digital geospatial data content is a growing concern. Geospatial data are public records, many of which need to be preserved for their legal, fiscal, analytical and historic value. Critical information captured in geospatial datasets include aerial imagery, land records, transportation, regulatory data, demographics, governmental boundaries and marine and natural resources.
The N.C. Geographic Information Coordinating Council has been involved in this effort through its vision for NC OneMap, which states that “historical and temporal data will be maintained and available.” Work is progressing on several fronts to build local and state government awareness about the need to archive and preserve data assets for the long term, and to provide the tools to assist in that effort. Achievements include guidance documents, projects to develop concepts and practices and the NC OneMap Retention Schedule.
Archival and Long-Term Access
The Archival and Long-Term Access Ad Hoc Committee framed the issue in 2007 for North Carolina and considered numerous aspects of this community-wide problem. They suggested guidelines and made three recommendations involving records retention related to geospatial public information.
The committee issued a final report on Archival and Long-Term Access, which was adopted by the GICC in November 2008.
Library of Congress Support
Two Library of Congress grants have furthered North Carolina’s efforts to tackle this important work. The GeoMAPP project (2008-2011) and the “North Carolina Geospatial Data Archiving Project (2004-2009) were funded as part of the National Digital Information Infrastructure and Preservation Program. The projects considered aspects of digital geospatial archiving such as content standards, digital rights, repositories and ingest workflows on a local and state level, as well as records retention schedules. Government digital geospatial records are valuable public documents, so their archival preservation should become part of agency business processes.
Read more about the Library of Congress National Digital Data Information Infrastructure and Preservation Program.
This grant paired state government archives staff with geospatial experts to investigate the issues surrounding the preservation of at-risk geospatial content. CGIA and State Archives led a four-year, multi-state project to explore methods for preserving at-risk geospatial data. The partners included the states of Kentucky, Montana, North Carolina and Utah and with active participation from information partners in 14 other states who participated in project meetings. Library of Congress and National Records and Archives Administration staff were active participants in the effort. The project team investigated the policies, process, inventory, technical infrastructure, storage capacity and funding issues involved in ensuring long-term access to data. The NC OneMap program is essential to the development of successful preservation strategies because it provides the technical and social interface – the organized data structure – for geospatial archiving.
GeoMAPP Project Deliverables
See the GeoMAPP website to read the interim and final reports documenting the interim processes, technical white papers and business planning tools.
State Archives of North Carolina
The State Archives of North Carolina provides access to a listing of the data through an online catalog called MARS, a database of archival holdings. Users cannot download the data from MARS, but a limited number of datasets can be downloaded from a tool called ContentDM. Additional datasets will be available soon. ContentDM was built for images but also enables access to other types of datasets online. The metadata record is provided as an html file to enable users to assess whether a dataset meets their needs. PDF files enable users to access a snapshot and preview the dataset.
The State Archives initiated a formal process for geoarchiving in collaboration with CGIA. The NC OneMap Retention Schedule is adopted and guiding retention of datasets stored in the NC OneMap database. For the statewide orthoimagery program, the plan is to archive copies of imagery captured in 2010 in one of four regions of the state when a new set of orthoimagery for the corresponding region is published in NC OneMap. Imagery captured in 2012 in the coastal plain region began a phased approach to refreshing orthoimagery. Imagery datasets require significant disk storage space, so the phased approach will be more practical than retaining the statewide 2010 imagery all at once. By 2016, the four-year cycle will begin again in the coastal plain region. The State Archives will continue involvement with the GICC and its work groups, implementing the business case documents and encouraging discussion about preservation funding during project planning