Chuck Swanson
Project Leader, Civil Engineer
Autodesk

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For almost 200 years, the San Francisco Presidio has guarded California's Golden Gate, protecting the state–and the country–from intruders running the gamut from pirates to the Axis forces. The Ohlone Indians, Spain, Mexico, and, finally, the United States, have all recognized the strategic importance of the site and have held sway there at various times in history.

However, with the Cold War at an end and attack by sea unlikely, the San Francisco Presidio has been targeted for closure by the 1989 Base Closure Act.

Today, the Presidio is being transformed from a military post to a one-of-a-kind national park. The Presidio's new role symbolizes the swords-to-plowshares concept.

The transformation of the 1,480-acre plot of land began in late 1994 when the post was turned over to the National Park Service (NPS). Although the Presidio has become part of the NPS system, the U.S. Army will continue to have a presence on the Presidio by occupying about one-third of the building and housing space. The National Parks Service is now transforming the Presidio by converting a variety of buildings and changing land use in several areas of the park.

The conversion from a U.S. Army post into a national park promises to create a "global center dedicated to addressing the world's most critical environmental, social, and cultural challenges."

The work of meeting those challenges will occur in almost 600 structures–510 of them historic–that will be preserved under the Final General Management Plan (FGMP). Various uses are under consideration for these structures, ranging from innovative community service programs, to a global think tank, to ongoing scientific and medical research at Letterman Hospital.

The FGMP also calls for the protection, preservation, and restoration of the natural landscape. The site will be used as a "global laboratory to create models of environmental sustainability, perfecting practices that can be transferred to communities worldwide." While many features, such as the National Cemetery and the Pet Cemetery will be retained, much of the land–almost two-thirds of the Presidio–will be open space.

The 300 acre Presidio forest will be restored and preserved as part of the cultural landscape. Streams previously diverted will once again flow through the Presidio. Approximately 276 non-historic buildings will be removed to help restore environmental integrity to the area. Most dramatically, a surplus airfield will be removed and the area restored to bay shore wetlands and sand dunes.

To preserve, restore, and maintain both the structures and the land requires a complex infrastructure. The Presidio is unique in that it is a significant archaeological and environmental site, as well as a small town. It needs the water, electrical, sewer, and road systems required by any small town, and this infrastructure must be evaluated and repaired.

Because of the Presidio's unique status, the NPS faces tasks well beyond those it normally expects to perform. Personnel must not only apply the skills required to maintain a rural national park, but also skills normally reserved for the city planner, environmentalist, and archaeologist. According to the Department of the Interior Secretary Bruce Babbit, "The Presidio Plan undertakes a scope and complexity that we have never approached in the National Park Service."

To handle such scope and complexity and to facilitate the planning process and support future operations, the NPS Presidio Transition Team developed a geographic information system (GIS) referred to as the Presidio Graphic Management Information System (PGMIS). The PGMIS is built around three major components: AutoCADr (Autodesk, Inc., Sausalito, Calif.), a design and drafting engine that is the foundation of the Geographic Data Models (GDMs) upon which the system is built; FMS (Facility Mapping Systems, Inc., Mill Valley, Calif.) a set of ready-to-use Automated Mapping/Geographic Information System (AM/GIS) Application Solutions that runs inside AutoCAD and serve as the glue linking drawing and text data; and dBASE 4 (Borland International, Inc., Santa Cruz, Calif.), a database management system that stores attribute and historical data. Through FMS, the PGMIS also links to Lotus 1-2-3 (Lotus Corp., Cambridge, Mass.) and other spreadsheet products to facilitate budgeting and predict labor requirements.

The PGMIS has three major goals, the first of which is to serve as a planning tool to aid in the base-conversion process. Planners must assess what currently exists on the site, determine possible uses and weigh the impact that each might have on the environment and the cultural and historic nature of the Presidio. They must also determine the state of the infrastructure and estimate costs for the entire conversion.

To handle these tasks, planners need the key computer technologies provided by the PGMIS: computer-aided design (CAD), AM/GIS, a powerful database, and spreadsheets. They must also be able to move easily from one application to another, obtaining or transferring data as needed from any source.

The second goal is to present these complex alternatives to the public, decision makers, and to other government agencies in an easily understandable format. This requires superior graphic manipulation and easy access to volumes of information to generate the desired displays and reports.

Finally, the PGMIS will be a primary tool not only in the conversion process itself, but also in ongoing maintenance and support of the site. It must, therefore, be easy to use and update.

Old Maps, Novice Users Pose Challenges

To develop the PGMIS, the Transition Team faced formidable challenges, not the least of which were the Army's 20,000 paper maps of the Presidio, some so old that they easily claim historic value. Their modern counterparts, primarily D- and E-sized maps, were drawn to a variety of scales. The Army had digitized only the base maps of primary utility systems. The remaining are of buildings and periodic improvements and changes.

The next problem centered around resolution of conflicts over land and building use. The Team had to first determine what existed, then what the Presidio might look like in the future and, finally, how to get from the present to the future by looking at the relationships among various elements within the park.

For example, if native plants are restored in one area, how will they affect runoff in another? Will buildings or roads flood? Will another habitat be destroyed? In addition, community and commercial organizations presented a range of ideas for the Presidio's future use. These interests had to be weighed against one another as well as against the cultural and environmental impact they would have on the site. To resolve these conflicts and ensure the best possible uses for the new national park would require sophisticated "what-if" capabilities in the computer software.

Once these determinations were made, the Team had to present the conversion plan to the public and to other government agencies. Complex, in-depth information had to be depicted graphically, so that it could be quickly and easily grasped without thumbing through pages and pages of text. Drawings and maps had to be produced showing how a certain area might look after conversion, to give interested parties a clear picture of the end result.

Finally, and perhaps most importantly, the system had to be simple and easy to use, not only by the Transition Team, but by anyone involved in the conversion and the ongoing maintenance of buildings, infrastructure and land. The PGMIS had to be designed so that landscapers and gardeners, architects and plumbers and the community groups and businesses involved with the Presidio could quickly and easily obtain, understand and manipulate data

The Transition Team turned to industry-standard, off-the-shelf software that could run in a DOS or Windows environment. With such a system, it was felt that users could be trained quickly and easily.

While DOS versions would be used for development of the PGMIS, the system will eventually move into the Windows environment to provide better ease of use.

The current system comprises four 486 PCs, a Hewlett Packard III printer, an HP 650C plotter and an E-size scanner. Software includes AutoCAD Release 12, the FMS Application Solutions, and Lotus 1-2-3. In addition to dBASE, two NPS databases– Inventory Condition & Assessment and Maintenance & Management–are also linked into the system through FMS.

Building Geographic Data Models (GDMs)

The PGMIS is built upon numerous FMS GDMs, with the major ones being Buildings Management, Land Redevelopment and various Infrastructure models. The datasets of the GDMs are drawings and their related non-graphic data. Initially, architects and contractors were hired to assess the state of the Presidio buildings and infrastructure systems. They created for the Transition Team a 2MB database with all pertinent building and infrastructure data. Such information ranges from square footage to historical significance to condition. Areas requiring repair were targeted. This database and the two NPS databases serve as repositories for all attribute and other text data.

Meanwhile, the Army's digitized drawings were converted from the existing Intergraph system and stored in a 20MB drawing database as AutoCAD DWG files. Each GDM contains both the drawings and the database files, placing valuable data within easy reach of even novice users. AutoCAD SQL Interface (ASI) provides the interface between the graphic and non-graphic types of data.

The Buildings Management GDM was created first. A file was opened in FMS and the Army's base map was pulled into the file and, working in AutoCAD, the building footprints were traced onto it. Next, each of the 870 buildings was assigned a number. The FMS software automatically created a file for the building and imported all pertinent data from the database. It took approximately 30 seconds to create files for all 870 buildings. The buildings can be color-coded in a variety of ways, depending on the planners' needs.

For example, one map may indicate the age of the buildings, while another may be coded to indicate urgency of required repairs. The basic Infrastructure GDMs were created in much the same way, and quickly tested the system's mettle as an easy-to-use maintenance tool. The sanitary system was the first targeted for repairs, with all pipes scheduled for relining. The Transition Team brought in the maintenance worker in charge of the work. With no computer experience and minimal training, this worker was able to consult existing drawings of the system, correct them when the field work indicated errors in the maps and/or system schematics, and update them to indicate new additions or changes. The library of standard symbols provided through the FMS software contributed to this ease of use. Through simple click and drag procedures, the worker could add features to the drawings. The corresponding database files were automatically updated.

The Land Redevelopment GDM also contains drawing and data files within FMS. All drawings are in the process of being converted to the same scale that adheres to California's State Plane Co-ordinate System standard. To date, there are approximately nine overlays in this GDM. In addition to the six to eight base maps, these maps include dozens of "factor maps", ranging from archaeology to plant species to ground care areas. Working with the AutoCAD Data Extension (ADE) application, the PGMIS can easily build new maps by simply combining relevant parts of existing factor maps. ADE also enables users to query either single or multiple maps as they would a single database, because each feature within the graphic database is linked to its attribute data in the database. Whenever a new feature is created, a time stamp is assigned to it and a supporting data record in added to the nongraphic database, creating the necessary link. Subsequent changes to the drawing or map are automatically updated in the database, considerably simplifying document maintenance.

Prior to the introduction of ADE to the FMS solutions, all graphic data had to be in active memory in order to be queried. Given the PGMIS hardware, 5MB was the limit. Now, with ADE on board, the project team is able to query files in the ADE graphic database with greater speed than ever. PGMIS is able to generate data faster since only a desired portion of the GDMs is in active memory and the remaining remain inactive.

The GDMs, together with the software applications, provide the "what-if" tools the Presidio planners require. By combining intersecting layers in the Land Redevelopment module, for example, they can quickly determine the effects that even the simplest of changes will create. In the Infrastructure file, they can determine the best route for new water, sewer or electrical lines, while the Buildings GDM helps establish priorities for repairs.

In the future, the GDM will also be the primary tool for Presidio maintenance. Whenever changes are made, the workers in the field will be able to update the PGMIS quickly and easily. The GDMs also facilitate maintenance scheduling and planning for future needs.

The Transition Team estimates that 100 users will eventually use the PGMIS on a regular basis.

Public Presentations

More than 50 drawings and displays have been prepared in AutoCAD for public presentations, the FGMP, and the environmental impact report (EIR). The Transition Team ivided the Presidio into 13 planning areas, ranging from the Main Post and the Letterman Complex, with their heavy saturation of buildings, to the Coastal Bluffs, and Lobos Creek Valley, which are open land areas. For each of these 13 areas, the Team has produced one map showing existing land use and nother showing future use. Elevation and orthogonal drawings of buildings have also been produced.

The ability to generate reports and special displays through the FMS link will be a key took in the fund-raising efforts that the NPS plans to launch. Funds will be used to help finance ongoing operations of the new park and its resident programs. Significant data used in the FGMP and the EIR derive from the database portions of the GDMs. Each and every map, tabular report and statistical finding shown in the documents were either generated directly from plots and printouts or were based, in part, on such computer-generated maps, tables, and diagrams.

Awards and Benefits

The PGMIS has met its goals of serving as a planning, maintenance and presentation tool. It has saved the NPS the considerable sum of money that would have been required to install a workstation-based GIS system. Most importantly, it has taken the complexity out of what, at first glance, appeared to be an overwhelming task, imposing simplicity and ease of use on the entire conversion process. Finally, the Transition Team hopes that it has created the first offering from the Presidio to the outside world, particularly other Base-conversion sites: a simple tool for moving from swords to plowshares.

Now, as it embarks on its new role to serve as a "global laboratory for environmental restoration and sustainability," the PGMIS is being expanded to serve as a vital supporting resource to this mission. The PGMIS has delivered more than the Transition Team initially dared hope. More than 100 large displays and booklets were prepared to facilitate the planning and public participation stages of the project. The PGMIS cut costs by almost $500 per display. In addition, thousands of hours were cut out of the planning process as a result of the program. Future maintenance and upgrading of the promises to be equally fast. All Presidio records are now linked through the FMS Solution Application database. Both drawings and non-graphic data can be located quickly and easily. Because the data are interrelated and users can create numerous "what-if" scenarios, decision making is considerably enhanced. In fact, the PGMIS is so successful that it has received an award from URISA as an Exemplary Systems in Government award for Operations Automation.

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