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GIS

Spatial Technologies-City Combines CAD and GIS

30 Apr, 2005 By: James L. Sipes

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Garden Grove's GIS system blends Autodesk Map 3D and MapGuide.

Ever since GIS users tried to edit shapefiles and CAD users tried to analyze geospatial data, users have wanted to integrate the two technologies. Integrating the drawing and editing capabilities of CAD programs with the data analysis and management capabilities of GIS programs is, in many ways, blending the best of both worlds.

For CAD users, the migration to GIS programs can be amazingly frustrating. A long-time AutoCAD user told me that when he first started using ArcGIS, he couldn't believe how difficult it was to make simple edits to a parcel map showing property boundaries. He was accustomed to the snaps, orthos, grids, dynamic pans and zooms and other tools that made it easy to edit any line or shape. "Why don't GIS programs provide those tools?" he lamented.

There are many reasons, but the biggest one is that GIS programs are not intended for drawing, and they're not designed to have the kind of floating-point accuracy of CAD programs. GIS programs are geared toward compiling, analyzing and synthesizing geospatial data, making analytical tools much more important than drawing and editing tools.

Autodesk's Approach

For AutoCAD users, one of the simplest ways to start using GIS capabilities is to transition to Autodesk Map and MapGuide. The recently released Map 3D 2006 integrates CAD and GIS data with creation and editing tools and new geospatial features. Map 3D is a precision mapping application that provides much of the functionality expected in a GIS program. It's intended for designers, planners, cartographers, utility managers and other professionals seeking to add GIS capabilities to their traditional drawing and mapping projects.

One of the biggest strengths of Map 3D and MapGuide is that they take advantage of enhanced interoperability with other Autodesk and competitive GIS products. Map 3D is built on the AutoCAD software foundation so it can leverage all the capabilities of AutoCAD. It also provides productivity and analysis tools not available in AutoCAD. AutoCAD users will find it much easier to edit a shapefile in Map 3D than in a GIS program.

The Data Dance

One of the goals of the latest version of Map 3D is to make it easier to integrate GIS data. "There has been a big push to integrate spatial data. The idea is to bring it together in a central store and combine that with information from other departments within a city, such as accounting and customer relations," says Chris Bradshaw, vice president of Autodesk's Infrastructure Solutions Division. Bradshaw says that Map 3D is particularly adept at pulling together data from different sources.

Map 3D supports AutoCAD DWG and DXF formats; Arc/Info coverages, exports and shapefiles; MapInfo MIF/MID formats; MicroStation DGN files; spatial data transfer standards; GML 2 (geography markup language) formats; and raster formats such as GeoTiff, Geospot, JPG, Earth Resource Mapping's ECW and LizardTech's MrSID. Map 3D also provides links directly to external warehouses, including Microsoft SQL Server, Oracle, Paradox, dBase V and III, Microsoft Access and other ODBC-compliant databases. Because Map 3D can read Autodesk's DWG file format, there are no problems with integrating data from other Autodesk products, including older versions.

The ability to work with so many different file formats in Map 3D makes it even easier for organizations to unlock spatial data from proprietary systems and share it with other departments within the organization. "When you have data that has to flow from the engineering world to the GIS world, you can carry the level of detail with you," says Mark Christian, a member of the Autodesk Infrastructure Solutions Division support team. "There is no loss of quality of the data."

Map 3D Features

Map 3D 2006 offers a number of features that should be of interest to existing and potential users. To start, the existing interface for Map 3D doesn't look like AutoCAD anymore (figure 1). "The older interface was kind of scary to some GIS users, so we worked at making it more accessible," notes Christian. The new interface for Map 3D is simpler, less cluttered and cleaner. The menu and toolbar structure is also much more intuitive and logical than earlier versions that had a single map menu. Legacy users can switch back to the Map classic interface.

Figure 1. The new interface for Map 3D 2006 is simpler and more intuitive than older versions of the software.

As its name suggests, Map 3D includes tools for creating and editing 3D shapes and surfaces, such as contours, surface triangles, elevations, slope thematics, surface face direction, watershed areas and grid and slope arrows. It can also read 3D data from ASCII, LandXML and DEM files. 3D surfaces can be quickly edited using standard Map 3D tools such as grip editing, erasing and moving. The 3D surfaces can then be analyzed using the analytical tools, rendered for presentations or displays, and even exported to other applications if necessary.

With the versioning feature, users can add data and make sure it's correct before adding it to a project. "It creates a series of drawings that are attached to a project, and different people can access the drawings and data at the same time," says Christian. This helps protect original data. Use Map Book to create a tiled map consisting of a series of multipage DWFs that are linked together. Map Book can be used to create either paper maps or electronic maps (figure 2).

Figure 2. Map Book can be used to create either paper or electronic maps that include navigational arrows.

Autodesk Map 3D users typically work with multiple drawings and large data sets that are more suited to GIS programs than to CAD programs. Map 3D does a much better job of handling large data sets than does AutoCAD. Note, however, that although Map 3D is touted as having "full GIS functionality," it does not have the same tools for spatial analysis and data integration as does a program such as ESRI's ArcGIS.

Garden Grove Case Study

Garden Grove is an urban community of 169,000 residents in Orange County, California. The city wanted to implement a citywide GIS system so it could create accurate parcel information and integrate all geographical data with maps. It also wanted a system that could be operated by existing staff and that would be accessible to all city staff via a city intranet and to all city residents via the Internet.

Garden Grove looked at the programs other cities implemented. Many had established a central GIS department that handled all geospatial mapping, editing and maintenance. Each department would send its requests to the GIS department, and then wait until the department had time to complete that particular project. "We noticed that frequently GIS became something of a bottleneck," says Charles Kalil, the information systems manager for the city. "We didn't want that to happen in Garden Grove."

Being able to incorporate legacy data was an important part of the decision-making process. With a limited budget, Garden Grove needed to be able to transfer its existing digital files with minimal effort.

The two options the city looked at were ESRI's ArcInfo and ArcView, and the new Autodesk MapGuide. The city decided to go with MapGuide for several reasons. The hardware and software cost of MapGuide was less than that of ArcView. In addition, in 1995, when the city was trying to decide what software to use, ArcView was available only with client/server architecture. The Internet model of MapGuide was better suited to the decentralized implementation the city wanted.

With this approach, the city centralized all data, but departments continued to do the work they had always done (figure 3). Everyone works together to create, modify and maintain GIS data layers. This approach helps keep down cost of implementing the city's GIS, and resulted in the creation of only one new position, the GIS coordinator. The city also found the transition to Map and MapGuide fairly easy because several city staff members already had experience with AutoCAD (figure 4).

Figure 3. With its decentralized approach, Garden Grove staff can access GIS data, such as this land-use map, as a part of day-to-day operations.

Budget Concerns

Budget was one of the primary reasons the city went with Map 3D and MapGuide. "GIS is something that was sorely missing in Garden Grove, but we needed to meet our needs within a limited budget of around $100,000," says Kalil. By far the biggest cost of implementation was purchasing parcel data from Orange County. The city paid a fee of $2 per parcel for one-time access to the data for about 40,000 parcels. Although the $80,000 price tag was fairly steep, this parcel layer was the foundation on which the whole GIS mapping program was built. After purchasing the original data, the city took over responsibility for updating its own parcel layer. This approach was not only cost effective, but allowed the city to update information much quicker than the county did.

Figure 4. Garden Grove found the transition to Map 3D to be fairly easy, in large part because some city staff had experience with AutoCAD. CAD base maps are an essential part of the citys GIS approach.

Day-to-Day Uses

According to Jim Deyo, the GIS coordinator for Garden Grove, the city is making extensive use of its GIS capabilities for many day-to-day activities. The dynamic nature of the city's GIS has changed how city staff is able to access data. It's added and updated on a continual basis by city workers, and the amount of information available is significant. The city primarily uses Map 3D and MapGuide, but it still has the need for GIS software. "We still use ESRI products, but because Map 3D can read and write shapefiles,it's a simple process to exchange data between the two," notes Kalil.

One of the first things the city did was to develop standards for AutoCAD drawings, so that drawings submitted by consultants could easily be added to the city's new GIS program. The city currently requires that developers submit digital drawings for each new project in any of the formats that Map 3D reads, including DWG files, shapefiles, MapInfo files and numerous other file formats. The submittions are then rubber-sheeted to line up with existing parcel information.

For city staff, a GIS menu is available through the city's intranet, with different sections set up for different departments within the city. For example, city staff can access all violations of city codes, map all of these violations and then pull up each site to review the specific problem for that property. All of this can be done in real time.

"In the public works department, our sewer guys are always in the field checking pipes, manholes and other features that may have an impact on their work," says Deyo. "We track manhole overflows, hotspots and cleaning history, and workers can see the actual reports and pictures that were taken during the call. We also use it for data entry. For example, by clicking on a line, our staff can add comments or make changes to existing data."

Implementation of Garden Grove's GIS system has resulted in improved service level and response time to constituents. The implementation has also resulted in significant time savings for the city. "A person will come into the front counter and ask for information about a specific parcel. What used to take 15 or 20 minutes now takes about 15 seconds," adds Deyo. Property owners, on their own or with the help of city staff, can search for their property based on address or parcel number. They can see the parcel on screen, zoom in for greater detail and then turn layers on or off to answer questions about floodplains, zoning, sewer problem areas and other characteristics. When a user double-clicks on a parcel, additional information comes up, including building permits, water customer, address information, county assessor information and business licenses. Older building permits are archived as TIF files, and they too can be pulled up.

Garden Grove uses Map primarily as an editing tool, but does create new maps. "We use Map to handle the digital submissions as they come in, and our engineers use Map to create new drawings," says Deyo. Individual departments create their own drawings. The traffic division, for example, produces its own striping plans, intersections and street improvement plans.

Right now, field crews for the city don't have access to GIS technology in the field, but they're looking at different wireless technologies to address this issue. "We have been looking at Verizon because it provides broadband out in the field," says Kalil. The city is still a couple of months away from implementing this type of mobile GIS application.

Public Access

It was important to the city of Garden Grove that all residents have access to the city's GIS information. From the city's Internet home page, individuals can access maps of any part of the city using Autodesk MapGuide. They can access their property and pull up all information online. The city also wanted users to be able to generate their own maps—they can turn data layers on and off and print out the resulting maps. The Internet site uses a Java plug-in to add flexibility to the system. Citizens like the idea of being able to access property information from their own homes. This cuts down on the demands on city employees, who can now focus their energies on other projects.

James L. Sipes is the founding principal of Sand County Studios in Seattle, Washington. Reach him at jsipes@sandcountystudios.com.