Did you know that two US presidential Executive Orders (EOs), considered together, mandate the convergence of building information and geospatial information in Federal projects? EO 12906 (the 1994 "NSDI" Executive Order signed by President Clinton) establishes a requirement for geospatial information, including building footprints. EO 13327 (signed by President Bush in 2004 to promote efficient and economical use of Federal real property) augments the previous Executive Order with a requirement for real property life-cycle information about federal buildings. The value of the National Spatial Data Infrastructure (NSDI) has been recognized explicitly in the natural resource and environment world - it sprang from those roots - but there is less awareness of the NSDI in federal real property management.

In 1994, the year of EO 12906 and the founding of the OGC, the cost of geospatial data non-interoperability in the US - redundant data collection, costly data conversion, inability to share data developed with different data models, etc. - was reported to be about $14 billion/year. Today, the cost of non-interoperability in the U.S. capital facilities industry alone is about the same, $14 billion/year, according to a recent study (PDF) prepared for the National Institute of Standards (NIST) by RTI International and the Logistic Management Institute. $14 billion is about 5% of the US construction industry market.

The "non-interoperability waste factor" in the Architecture/Engineering/Construction (AEC) and real estate worlds has causes similar to the causes of the non-interoperability waste factor in the geospatial world. A multitude of professional roles, including engineer, architect, consultant, contractor/builder, supplier, project manager, permitting agency, building manager, maintenance contractor, owner, planner, developer, banker, broker, insurance agent, attorney and CPA, require information about a building, much of it information that others have quite likely already collected. At every stage in the life cycle of a building, data are collected. Much of these data will still be valuable in subsequent stages of development.

Typically - and unfortunately - professionals involved with the building process develop and use their portion of the data only for a brief period; and then those data are not shared with others in the building process; and finally, even worse, they are lost. This is partly because they use different types and brands of software that don't communicate, partly because they use different data models, and partly because appropriate data sharing and archiving policies are not in place. Ideally, as with geospatial data, building data should be collected once and used many times, instead of being collected many times to be used only once. And, to enable easy and automated exchange of data and processing instructions, the systems should employ open interfaces and encodings that hide the systems' internal differences.

CAD/geospatial convergence is necessary because the professionals in the AEC and real estate worlds often need to use building information in the context of map layers such as the cadastre, communications, demographics, environmental hazards, land use and zoning, land cover, soil, transportation, utilities, hydrography and elevation.

Seamless integration of building data and geospatial data helps owners, buyers and mortgage institutions define the value of the building. It helps with design visualization and coordination, owner/tenant communication, construction sequencing, energy simulation, traffic/egress simulation, facility management and other activities. Homeland Security, too, requires the ability to share data across organizations, at all levels.

Increasingly, such tasks are being analyzed as workflows, the flow of activities and interactions in a project. Much of this "flow" is information flow. The purpose of such analysis is to engineer more efficient workflows that take full advantage of information technology.

Where workflows involve the cooperation of multiple participants in independent organizations working on multiple tasks, the only reasonable approach is to use an open architecture and an interoperable software environment. Through an array of open, consensus-derived Information Technology standards, one step can flow smoothly into the next and all project components and documents can be integrated to help people successfully accomplish their piece of a project.

Significant progress toward this goal has been made. It was not true in 1994, but it is often true today that the seamless flow of information can include, to some degree, engineering and GIS data, image processing, desktop mapping, location services, photogrammetry and laser scans.

The OGC's CAD-GIS Interoperability Working Group is one important arena in which progress toward this goal continues. At the 55th OGC Technical Committee meeting in Bonn, Germany in November, Mark Reichardt of the OGC gave a report on International Alliance for Interoperability (IAI) collaboration to achieve Industry Foundation Classes (IFC) revisions and on the National Building Information Model (BIM) Standard in U.S., activities in which the OGC is involved. Thomas Kolbe at the University of Bonn provided a CityGML update, and Carsten Roensdorf spoke about 3D and GML at the Ordnance Survey in Great Britain. Paul Scarponcini of Bentley Systems provided an update on TransXML, a US national effort to develop broadly accepted public domain XML and GML schemas for exchange of transportation data. Øivind Rooth of the National Office of Building Technology and Administration, Oslo, described the IFC/IFG Norway Use Case Articulation. Josh Lieberman of Traverse Technologies and Udo Quadt of the University of Bonn reported on CAD-GIS coordination with the OGC Web Terrain Service (WTS) and W3DS.

At the meeting, George Percivall of the OGC spoke about the potential for doing work in this area in OWS-4, OGC's next major Interoperability Initiative. OWS-4 is still in the planning stage, but it is expected to kick off this spring. If you have interest in helping to determine the technical scope of OWS-4, whether your goals involve CAD or not, email George Percivall. OGC's Interoperability Initiatives provide an unmatched opportunity to achieve immediate, practical, interoperability in your microcosm, which can result, through a shared and open effort, in a standard that benefits the whole world. It doesn't require an Executive order of the President of the United States.