| Creating Public/Private Partnerships
GDT and ESRI collaborate on creation of on-line spatial data maintenance program
By John Auble Street centerline databases form the backbone of GIS and computer mapping applications. From environmental mapping to routing applications to Web locator services, an up-to-date, fully attributed street centerline database is the critical component. But keeping a national street centerline database up-to-date and accurate is a mammoth task that requires assembling information from either knowledgeable sources or field collection efforts and then converting that information into a GIS environment. And this task must be repeated each time new roads are built or new subdivisions are developed.
Usually, the best sources of information on new streets and subdivisions are the local government agencies which approve new developments or which must collect that information to support their mission. But these agencies often lack the time, staff, or interest to maintain a current GIS database of their communities. Commercial vendors, such as Geographic Data Technology (GDT), may have the time and resources to maintain a GIS database, but they aren't the first to know of changes or additions to street and address information. GDT's new Community Updateª program seeks to bridge the gap between agencies with first-hand knowledge of street and address information and the ongoing maintenance of the nation's spatial data infrastructure.
The concept behind Community Update is simple: Take the street and address knowledge that exists at the local government level, turn it over to an expert in data compilation and management, and then "reward" the community participants with a professionally maintained street database. Built in collaboration with ESRI, the Community Update program uses an Internet interface that allows participating agencies to quickly and easily send street and address information to GDT. As the data compiler, GDT adds information from other resources to ensure that the final GIS data set contains the most current and accurate information. The participating agencies, ESRI, and GDT are lending their individual strengths to an effort that will ultimately result in a dynamic and evolving national street centerline database that can be used in government, business, and consumer applications.
Using ESRI's ArcIMSª software, Community Update allows local knowledge providers to access GDT's database free of charge over the Internet. These agencies can electronically add suggested new features and related information to the data set and submit that information via the Internet directly to GDT, which will validate the information and add other enhancements. The revised data will then be returned to the local agencies at no cost for use within their own applications.
To participate in Community Update, government agencies must first apply for the program. Acceptance into the program is based on the agency's ability to provide meaningful database updates and its willingness to commit to providing those updates on an ongoing basis. The ideal Community Update participant is a map-savvy worker in a government office that is among the first to know of new street and address information for its locality. Often this will be someone who would like to build an accurate local GIS data set because the information is critical to his or her job.
Once accepted into the program, the participating agency downloads GDT's current data for its region. Using Community Update's Map Mark-Up tool, the participant can draw in new features such as road segments or landmarks, as well as attribute information such as address ranges and street names. This process is the electronic equivalent of adding changes to an acetate layer overlaid on an existing paper map. The Map Mark-Up tool allows the participant to add new information through a graphic user interface without having to worry about precise coordinate information. The MapNotes tool provides an electronic Post-itª Note that allows participants to provide comments or explanations of their edits.
Most agencies already collect update information and struggle to incorporate it into an existing GIS dataset. For many of these agencies, maintaining a GIS dataset is a burden that must be done before they can accomplish their real mission-that of planning and providing services to their constituents. For these agencies, Community Update will simplify the work they already do by allowing them to forward the update information to GDT for inclusion in a GIS dataset. Some agencies may have the update information available, but lack the time or personnel to incorporate that information into a GIS or to keep their existing GIS database as up-to-date as they would like. For these agencies, Community Update provides an opportunity to acquire an up-to-date data set without time-consuming GIS maintenance activities.
After the agency adds suggested new features and related information to the GDT data set it has downloaded, it submits that information directly to GDT via the Internet. At GDT, the information is imported into editing software and verified by one of GDT's nearly 200 Digital Mapping Technicians. The technician will use aerial or satellite imagery to verify and correct the positioning of suggested new features. Using GDT's proprietary technology, the mapping technician will re-align the nodes of the new feature to match the underlying imagery, thus ensuring the coordinate positional accuracy of the addition. GDT will use its monthly United States Postal Service (USPS) updates to include any new addressing information for the area, and Digital Mapping Technicians will check GDT's vast repository of resource holdings to see if there is any additional information (such as landmarks) for the area. All changes are subject to GDT's rigorous quality control process. Once the enhancements are completed and verified, the updated information will be added to GDT's core database and the participant will be notified that his data updates are available for download via the Internet. Participating agencies are free to use the enhanced data within their own applications free of charge.
Community Update builds on GDT's existing Cooperative Research and Development Agreement (CRADA) with the US Bureau of Census. The CRADA, signed in 1997, is a 5-year partnership to jointly explore ways to improve the collection and sharing of the basic geographic information needed to maintain the national spatial data infrastructure. But while the CRADA looks at the national data infrastructure from a big-picture perspective, Community Update brings the idea down to the local level where much of the data maintenance work is done on a day-by-day basis. Community Update helps local agencies keep their own databases current and accurate while at the same time helping to create a dynamic and evolving national spatial data infrastructure.
Community Update also supports the National Academy of Science's Mapping Science Committee's vision for a National Street Centerline Spatial Database. Nearly 5 years ago, the Mapping Science Committee outlined its vision for a National Spatial Data Infrastructure that would include a street centerline database built from the Census Bureau's TIGER database.
In "A Data Foundation for the National Spatial Infrastructure," the committee noted that, "The TIGER files could be integrated with the foundation by the following actions: -Improving coordinate accuracy using orthorectified imagery that is tied to the geodetic control network; -Completing and improving street and address coverage in partnerships with the US Postal Service, 911 emergency agencies, state and local governments, and the private sector; and -Establishing an ongoing update facility employing local government partnerships for timely information (transactional updates) about new streets."
Many have viewed this as strictly a government function; however, there is no single governmental agency charged with maintaining the nation's spatial data infrastructure. It is becoming increasingly clear that private industries may be in the best position to make this vision a reality. GDT, for example, has worked with the USPS, 911 agencies, state and local governments, and business customers to help create and maintain its digital street file, which was originally based on TIGER. And, GDT now uses orthorectified imagery to enhance the coordinate accuracy of its attribute-rich database. By incorporating its private database into an ongoing update process that involves local governments, GDT can tie together the three components of the Mapping Science Committee's recommendations. Just as NASA pioneered communication satellites in the 1960s and then turned the torch over to private industry when markets developed, perhaps now is the time for commercial vendors to step in with their contributions to the National Spatial Data Infrastructure.
At the National Geodata Forum in June, the Federal Geographic Data Committee encouraged innovation, sharing, and cooperation among individual organizations to help build the National Spatial Data Infrastructure. It was in this atmosphere of public-private partnership that ESRI's Jack Dangermond and GDT's Don Cooke agreed to forge ahead with Community Update.
The Community Update process outlined above is aimed at local governments; however, GDT is actively looking for ways to bring regional and state governments into the process as well. Many regional and state governments have existing communication loops with local governments. Rather than supplant those, Community Update will seek to support and enhance those existing processes with the ultimate goal of easing the update and maintenance work now foisted upon governmental agencies. GDT is also working with the Census Bureau to ensure that the implementation of the Community Update concept makes sense from a national perspective.
The goal of Community Update is a simple, yet significant, one: Unite the government and private entities involved in updating street centerline database and reduce the duplication of effort to create a dynamic, constantly evolving National Spatial Data Infrastructure. About the Author:
John Auble is the manager for GDT's Community Update program. Auble has worked with governments and businesses in GIS and remote sensing applications. Most recently he was responsible for GIS software development, marketing, and business development for Clark University's Clark Labs in rcester, Massachusetts. Back |
