GIS Tech News (#113)

4 Apr, 2012 By: Cadalyst Staff

Tech Trends: BIM vs. GIS

When it comes to managing facilities and infrastructure, which technology provides the information that you need in the way you need it? The answer might be: both.

By Heather Livingston

In facilities management, one question seems to be on everyone's mind these days: BIM or GIS? Without a doubt, both options have a lot to offer when it comes to wrangling all the data involved in operating a facility. BIM (building information modeling) offers detailed 3D visualization and the ability to organize huge volumes of data related to buildings. A GIS (geographic information system) is highly customizable, well equipped for analysis, and ideal for projects in a campus or multi-site environment. Which program or process is better for FM depends entirely on whom you ask. In speaking with a variety of experts, one thing became clear: You're not likely to find much consensus.

At Autodesk University 2011, one seminar explored "The Great BIM Versus GIS Debate." Hosted by Matt Ball, editor and cofounder of Vector1 Media, with cospeakers Peter Southwood and Michael Schlosser, both of Autodesk, this gathering was lively and full of strong opinions about the capabilities, strengths, and drawbacks of BIM and GIS in the FM arena.

Taking Sides

Southwood, a geospatial technical specialist, expressed his belief that BIM is best suited for managing data related to the building itself, whereas GIS is more applicable for everything outside buildings. What FM really needs, he said, is something to manage information on a large scale. He believes that CAD in a GIS system provides the single source of truth that's needed to analyze the data required for FM. Because 3D design programs such as Autodesk Revit don't yet have the ability to easily transfer data directly into a GIS model, CAD is the standard-bearer for maintaining accurate design data in a GIS system.

Schlosser wholeheartedly disagrees with Southwood. Although he, too, is a technical specialist and a geospatial subject matter expert, he is a bit of a BIM evangelist — although his appraisal of BIM is not a conventional one. "I would say the BIM model encompasses more than that," he argued during the seminar. "The BIM model can encompass an entire subdivision and not be just about an individual building, but could be about the behavior of that entire subdivision or campus. It can model vehicular traffic [and] pipes in the ground and analyze the flow of water through the ground. If I increase the density of the neighborhood, how does that impact the pipe capacity — and can the treatment facility handle it? I look at BIM as information modeling for the built environment," he said. Read more »
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cadalyst contributing editor Heather Livingston is a Wichita, Kansas–based freelance writer specializing in design, sustainability, and architectural technology.

Louisiana Utility Dispels GNSS Signal Shadow with Trimble Floodlight

Satellite shadow–reduction technology enables St. Charles Parish Waterworks crews to map infrastructure features under tree cover.

By Kevin Corbley

The last straw for utility personnel in St. Charles Parish, Louisiana, came when an underground water pipeline burst beneath a busy street. Traffic had to be diverted as the water continued to spill onto the pavement. An hour passed before workers from the Waterworks Department found the shutoff valve and stopped the deluge. The delay was caused by a faulty map that showed the valve's location on the wrong side of the street.

As is true for many local government departments, the St. Charles Waterworks relied on as-built drawings and sketches supplied by developers and engineering firms to keep the network of underground water pipes updated in its GIS. At the time, the parish had no other option because it lacked internal mapping capabilities. In 2008, St. Charles created a GIS Office to support mapping needs of all other parish departments and hired Luis Martinez to manage it. Fortunately, Martinez had been trained to use GNSS (global navigation satellite system) technology for GIS data collection in his previous position. He convinced the parish it would be cost-effective to invest in mapping- and survey-grade GNSS equipment and train personnel to use it as part of their daily operations.

"The first personnel we trained were the Waterworks and Public Works crews," said Martinez. He explained that Waterworks is responsible for maintaining, repairing, and upgrading the parish's network of above- and below-ground water pipelines. Public Works manages the storm protection and drainage infrastructure, such as catch basins, ditches, and levees.

The GIS Office maintains a parish-wide, Internet-accessible GIS comprising layers for nearly all departments. Aside from Public Works, the Waterworks Department has the most rapidly evolving geospatial data layers in the parish. With new water pipes being installed and old ones being replaced, the Waterworks infrastructure map is constantly in flux. Handheld GNSS-based GIS data collection units were seen as the ideal solution for keeping layers accurate and up to date.

Waterworks crews experienced problems with accuracy, however, when working beneath the stately oak trees that line many parish residential streets. The oak canopies deflect and partially block GNSS signals from reaching the receivers, impairing productivity through a phenomenon called satellite shadow. This same signal deflection problem often challenges mapping crews working among tall buildings in cities. Read more »
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Kevin Corbley is the founder and owner of Corbley Communications.

Mark Your Calendar: GIS Events

Point Cloud Processing and Scalable Terrain Models in Bentley Descartes
April 11, 2012
11 a.m. PT
At this complimentary webinar from Bentley, attendees can learn about the capabilities of Bentley Descartes v8i. Read more

FME World Tour 2012
April 16–September 25, 2012
Various cities
Safe Software is hosting this series of events, which will explore the new tools available to FME users and explain how to overcome data snares and interoperability riddles using FME software. Read more 

Be Together: Bentley User Conference
May 15–17, 2012
Philadelphia, Pennsylvania
Carrying the theme "Working Smarter, Together," this interactive learning event will give Bentley users the opportunity to enhance their skills, increase their knowledge of the latest technology, and network with peers, Bentley executives, and exhibitors. Read more

For a complete list of CAD meetings, conferences, training sessions, and more, check out our calendar of events on Are you hosting an event that you would like to include in our calendar? Submit details at least two weeks in advance to

What's New at

CADspeed Blog Post:
How Much RAM Should You Buy for a CAD Workstation?

Start with the minimum RAM recommendation for your primary software, then get a feel for how much more memory you'll get with incremental spending. Read more

CAD Manager's Toolbox: New Software — Is It a Go?
Which new releases are worth the time and money to implement? Read more

AutoCAD 2013 from the CAD Manager's Chair
You've heard about some of the new features already, but how will this release affect your users and their workflows? Read more

Cadalyst Labs Review: AutoCAD 2013
Autodesk's flagship product offers new cloud-based features to enhance file storage and collaboration, new 3D-to-2D functions, plus myriad small but very useful tools to make your everyday work easier. Read more

About the Author: Cadalyst Staff

Cadalyst Staff

Add comment

Note: Comments are moderated and will appear live after approval by the site moderator.

AutoCAD Tips!

Lynn Allen

In her easy-to-follow, friendly style, long-time Cadalyst contributing editor Lynn Allen guides you through a new feature or time-saving trick in every episode of her popular AutoCAD Video Tips. Subscribe to the free Cadalyst Video Picks newsletter, and we'll notify you every time a new video tip is published. All exclusively from Cadalyst!

Follow Lynn on TwitterFollow Lynn on Twitter

Do you use social media — such as Facebook or Twitter updates, YouTube videos, or discussion forums — for work-related purposes?
Yes, I regularly use such resources for work-related purposes.
Yes, but on a limited or infrequent basis.
No, because my employer frowns upon or prohibits doing so.
No, because I don’t have the time or interest.
Submit Vote

Download Cadalyst Magazine Special Edition