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A Prototype for USGS's The National Map
Delaware DataMIL: A Web-Based Mapping Collaboration
The most common problem people have when creating or viewing a map is currentness of the geographic information. Data producing agencies usually maintain their databases on an as-needed or continual basis. When the real world changes, those changes are reflected in the digital database. However, by the time this database gets to the user, the information is nearly always out of date. Is it possible for the user to access this real-time database? In cases where the user may have some knowledge that can improve the existing database, is it possible for the user to get that information back to the appropriate agency? If so, how?
Another prominent issue facing the geographic data user is the enormous amount of information available today. For instance, a researcher at the University of Delaware is studying population movement within the State. A quick search on the Web for transportation data reveals numerous options. Digital data of the roads in Delaware can be obtained from the Delaware Department of Transportation, U.S. Census Bureau's TIGER/Line files, United States Geological Survey (USGS) digital line graphs (DLG), or a number of private companies that charge a fee for a more accurate and current data set. How does the researcher select a data source without spending countless hours reading through metadata? Furthermore, can the researcher be sure that the roads data set will align properly with other data sets needed for the study such as local boundaries, land use areas, or water features?
The Delaware Data Mapping and Integration Laboratory (DataMIL) project attempts to solve these problems for users and maintainers of Delaware geographic data by deploying the basic Delaware Spatial Data Framework in one central--but distributed--application. More than just laying the foundation of the Delaware Geography Network, DataMIL acts as a true implementation of Esri's g.net principle. DataMIL is an interactive, online collaboratory to facilitate collection, integration, maintenance, distribution, and mapping of geographic framework data. DataMIL's primary objective is to provide an environment for local, state, and federal agencies and the general public to communicate and develop the most accurate, up-to-date geographic database possible for the State of Delaware. Simultaneously, DataMIL provides a central location where users can access all of Delaware's spatial data sets and be assured that these data sets work together and adhere to a high standard.
In its initial phase, the DataMIL project will principally serve State-wide layers of the Delaware Spatial Data Framework and USGS's The National Map. Delaware's framework includes transportation, elevation, aerial photography, land use/land cover, hydrography, geographic names, governmental units, geodetic control points, and tax parcels. This set of data, along with man-made structures, is consistent with data themes comprising The National Map. USGS's The National Map is the nation's topographic map for the 21st century. It is the USGS vision for a seamless, current, accurate, and consistent geographic database for the country. This concept can only be achieved through partnerships among the academic institutions, private companies, state and federal agencies, and the USGS. The Delaware DataMIL is a leading pilot project and provides Delaware's portion of The National Map.
From Mark Demulder, program coordinator, Cooperative Topographic Mapping, USGS: "Delaware's initiative is tightly aligned with The National Map vision. The Delaware consortium is leading the way to offer data and capabilities for the State that are the base for partnership development and extension of The National Map concept."
To achieve the goals outlined above, the DataMIL team chose Esri's ArcGIS technology as its GIS building block. Esri provides server (ArcIMS 4, ArcSDE 8.2) and client (ArcGIS Desktop 8.2, ArcIMS 4 Viewers) software in a distributed GIS environment. Additionally, WebBoard 5 (Akiva Idea Technologies) was selected as the base for user interaction with the data stewards. DataMIL is built on open standards and specifications formulated by national and international standards committees on data exchange and development. These include the Open GIS Consortium Web Map Server standards and Federal Geographic Data Committee metadata standards.
Within DataMIL's g.net architecture, three applications compose its core functionality: the Portal, the Map Production Laboratory, and the Discussion Forums. General users will spend most of their time in DataMIL with these three applications. For more advanced users, the Delaware Metadata Explorer and the Data Integration Laboratory complete the picture.
The Portal is the entry to the Delaware DataMIL and provides project information and links to resources and describes the options available to the user. All DataMIL applications can be accessed from the Portal. The Map Production Laboratory is an ArcIMS application offering image, feature, and ArcMap image services. It provides capabilities to browse and select digital geographic data layers to create maps of any part of the State. Users can create and view maps on the Web; search for any Delaware name in the U.S. Geographic Names Information System (GNIS) or DelDOT Road Name database; or create high-quality, downloadable, printable maps with the familiar look and feel of USGS topographical maps. Users can even download shapefiles and georeferenced images for inclusion in desktop GIS packages. In addition, they can connect directly to the ArcIMS DataMIL map services for further analysis with ArcGIS, ArcIMS, ArcExplorer, or ArcReader software.
A major goal of DataMIL is to foster ongoing discussions about Delaware's spatial data framework. The Web-based DataMIL Discussion Forums facilitate dialog between the agencies responsible for updating geographic data sets and the public that use those data sets. If, for example, someone found an apparent error in a map produced by the Map Production Laboratory, that user could electronically post an annotated copy of that map directly to a Discussion Forum. Each posting is addressed by the forum gatekeeper and forwarded to the appropriate data steward. The underlying concept is that citizens, scientists, urban planners, etc., have a keen awareness of changes that happen in their local vicinity. The forums provide a convenient and efficient mechanism for getting that information to data providers. In addition, the forums provide a place for data stewards to work collaboratively within and among cooperating agencies and departments to improve the State and national geographic databases.
The Delaware Metadata Explorer is a Web-based search engine connected to Delaware's National Spatial Data Infrastructure (NSDI) Metadata Clearinghouse node. This node is maintained by the University of Delaware on behalf of, and in cooperation with, the entire Delaware GIS community. This service is built around Esri's ArcIMS Metadata Services. Metadata is a standardized description of data--the who, what, when, where, why, and how information. It describes such things as data quality, resolution, intended purpose, update frequency, and many of the technical details needed by GIS professionals who use the data for analysis and planning.
The Data Integration Laboratory completes Phase 1 of the DataMIL suite. This lab comprises an ArcIMS feature service viewed through a customized version of the ArcIMS--Java Viewer. Although this application requires higher system requirements on the user's computer, it provides higher-level functionality such as online editing for data stewards and the ability to add local data and external ArcIMS mapping services to the Web browser.
Collaboration Is the Key
The key to the entire DataMIL project, as it is in any Geography Network, is collaboration. In Delaware, the Delaware Geographic Data Committee (DGDC) coordinates geographic data and activities throughout the Delaware GIS community and makes recommendations when needed. The DGDC does not exert authority or control over any Delaware agency's actions. Likewise, at the federal level, the USGS does not mandate control over Delaware data. The USGS will partner where it can and produce data only when necessary. An appropriate local, state, or federal agency is identified as sole proprietor for each Delaware framework or layer of The National Map and has agreed to update the DataMIL server regularly. DataMIL services are already in use in support of municipal planning assistance by the Office of State Planning Coordination, geological research of the Delaware inland bays by the Delaware Geological Survey, and coastal studies of the Delaware Department of Natural Resources and Environmental Control.
As each agency updates its database, it also updates the associated metadata. Both types of information must be incorporated into DataMIL. To update the spatial database, agencies have the option of running their own ArcIMS services or transferring data sets to the DataMIL server. To update the metadata, each data steward is provided an account on the DataMIL server to update the Metadata Clearinghouse. Through ArcCatalog, the agency can connect to the ArcIMS metadata service and simply drag and drop its metadata onto the server. This demonstrates the importance of the collaborative process. This process is defined by memoranda of agreement and coordinated by the Delaware Spatial Data Implementation Team (I-Team) and is the true backbone of the Delaware DataMIL.
Several organizations played key roles in the initial planning and deployment of the DataMIL project. DataMIL is a partnership of the Delaware Geological Survey, the Delaware Office of State Planning Coordination, the University of Delaware, and the USGS. DataMIL is one of nine pilot projects of The National Map and is a primary project of the Delaware I-Team, the DGDC, and the State Mapping Advisory Committee. It is the only pilot of The National Map with statewide coverage and a complete, functioning Web-based implementation. At present, it is viewed within USGS as the potential prototype to achieve their vision of The National Map. "DataMIL constitutes the Delaware component of The National Map and serves as a model for federal-state-local partnerships across the nation," states Demulder.
The Delaware DataMIL project provides a technological, organizational, and operational geospatial data infrastructure for Delaware and the nation. For academic users, DataMIL is a powerful resource for classes and research across a wide range of disciplines and at all levels of sophistication. For municipal, county, state, and federal agencies, DataMIL provides access to a common set of base geospatial data and reduces data duplication and inefficient data sharing. For data providers, DataMIL provides new ways to help keep their data current. For the general public, DataMIL provides easy access to the State's common base of official geospatial data. This improves community awareness and informed participation in Delaware's land use and natural resource planning and policy development. These benefits all support the current national efforts in mapping as well as the Livable Delaware Initiative of Delaware's Governor Ruth Ann Minner.
Governor Minner says, "Dependable, accurate data and information are part of the shared knowledge infrastructure we need at all levels of government. Our Delaware GIS community has taken an important step forward, creating a new tool to ensure that Delawareans have access to the best possible data and information. Delaware was the first state at the start of the nation; now we're ready to be the first state in The National Map for the 21st century."
For more information, contact John Callahan, GIS technical lead, Research & Data Management Services, Information Technologies, University of Delaware (e-mail: email@example.com, tel.: 302-831-1978) or visit the Delaware DataMIL Web site (datamil.udel.edu). Visit nationalmap.usgs.gov for more information regarding USGS's The National Map.