A Review of the New 10th Edition Trip Generation Manual

By Bryant Ficek, PE, PTOE

As many of you know, the Institute of Transportation Engineers (ITE) released the 10^th Edition of their Trip Generation Manual earlier this month. As we detailed earlier, we provided a significant amount of data to this version (pat on the back here). Now that we’ve had a few days to review the new manual, here are our key findings:

• Having a PDF of the manual is great. We like to, and often do, work remotely. With a PDF on our network, we can access the trip generation information whenever we need it.
• The PDF could use better bookmarks. Right now, the PDF has shortcuts to land uses in groups of 100. For instance, you can easily reach the general office lands uses (ITE Land Use numbers 700 to 799), but then must page through to reach the specific Government Office Complex, ITE Land Use number 733. Since it’s a PDF, we think it could be easier to get to a single land use rather than a just a group.
• The Trip Generation Handbook, 3^rd Edition, has not been significantly updated from its release with the 9^th Edition of the Trip Generation Manual. Inconsistencies have been corrected and some data updated, but the basic recommended processes remain the same.
• The information has indeed greatly increased the number of land use types provided (22 more) and the number of studies per land use type (1,700 new sites). With the elimination of pre-1980 data, the trip generation content remains a reliable and trustworthy source of information for all traffic engineers.

[Free Trip Generation Data at TripGeneration.org]

Beyond the manual, the newest item is the Trip Generation Web App. Here’s our initial reaction to the online version:

• It’s basic. As far as we can tell, the web app presents the same information as available in the PDF. There are no real extras from using the web app right now.
• The customized graphs look nice. Enter the size of your independent variable and the graph reflects your value, showing the appropriate lines and trip generation. You can also zoom in on the data if needed. We don’t know if we will start using the graphs in our reports, but it’s nice to see them.
• It calculates the total trip ends. Enter the size of your independent variable and the calculated trip ends for the average rate and fitted curve, if available, is provided. It would be nice if it further sub-divided the information in the directional distribution of entering and exiting traffic.

In general, the 10^th Edition is a jump forward and we will continue to use it in our work. The web app is a nice start, but several more components could be added to improve the functionality of it (provide the directional distribution of entering and exiting, keep the entered independent value if shifting between time periods or settings or trip types to automatically see the differences, allow a greater ability to filter data such as by two variables, etc.). Until the web app is improved, we may end up using the PDF more than the online version.

Equally important, ITE continues to recommend collecting local data in many instances for your studies. Local data reflects your area’s driving patterns and other habits. Local data also gives you access to non-peak hour data and other information that could be valuable in your studies.

[Free Trip Generation Data at TripGeneration.org]

We’ve taken that recommendation to heart and collect local data on many, if not most, of our traffic studies. And we make that data available to you for free. This living document now includes over 10,500 hours of data and allows you to see the full 24-hour data collected. Go to TripGeneration.Org to download the raw data we’ve collected.