October 26


The Evolution of Free Trip Generation Data

By Mike Spack

October 26, 2017

ITE, trip gen, Trip Generation, TripGen.org, tripgeneration.org

By Mike Spack, PE, PTOE

I’ve seen a need for improving Trip Generation (a dataset of how much traffic enter/enters different land use types based on different variables with the largest United States-based dataset being the Institute of Transportation Engineers’ Trip Generation Manual).  Trip generation is at the heart of traffic forecasting and traffic impact studies, so I’ve written extensively about it over the years.  Here are a few of those posts:

As recommended in the Trip Generation Manual, we collect current/local trip generation data to supplement our traffic studies.  We decided to start sharing this data in 2015 (because we’re here to Improve Transportation Globally) through TripGeneration.org.  The latest dataset has more than 10,500 hours in it including data shared to us by other consultants and agencies. Our dataset includes apartments, fast casual dining, liquor stores, marijuana dispensaries, shopping centers, gas stations, housing and more.

[Get 10,500+ Hours of Free Trip Generation Data at TripGeneration.org]

As expected, we see variation between our current Minnesota based data and ITE’s data.  You can read about some of the more interesting differences in these posts:

I commend ITE for taking a huge step forward with the latest release of the Trip Generation Manual. I started TripGeneration.org to supplement ITE’s once a decade release of their dataset.  They’ve incorporated many of the features I’ve written about and I’m hopeful ITE’s system will be good enough, that we discontinue TripGeneration.org.  We’re also proud to be the number one private contributor to this 10th Edition of the Trip Generation Manual and expect to continue this tradition in the 11th edition!

[Get 10,500+ Hours of Free Trip Generation Data at TripGeneration.org]

It’s our 10th Anniversary – But the Gifts are for You!

Each week in October, we will be offering free and discounted items for our readers.  Here’s this week’s gifts for you.

Free Traffic Video Count. Attend a COUNTcloud demo and receive a free traffic video count. COUNTcloud is our traffic video processing service. It’s easy-to-use, and affordable. And the best part…there are no contacts to use our service!

FREE Guides: Download three of our most popular engineering (as rated by our readers!)

  1. Roundabout Primer
  2. Drive-through Queue Generation Report
  3. 16 Ways Autonomous Vehicles Will Change Land Developments

50% off Your Entire Purchase at Spack Academy.  Now through October 31, 2017 get 50% off your entire Spack Academy purchase when you use code MOT10 at check out.

  • Hello Mike
    My name is Molly Robbins and I live in North Idaho. My housing development, Foxtail, is being threatened by a huge 300 unit apartment complex that will be sitting on 17 acres alongside our land. We are scrambling to appeal the decision that was passed by P + Z on April 10th.
    The centerpiece of the applicants travel study was citing calculations from the 9th edition of the ITE manual. The engineer (who is supposedly an expert as a traffic engineer) presented the 17 acre apt complex’s footprint on top of a Walmart footprint that is similar in size. He then calculated trip generation numbers and compared the numbers showing the Big Box store has higher numbers than what a 17 acre apt complex would generate. This Early Dawn Special Use permit is about building a huge complex in an area that has woefully undeveloped roads. Our housing development of 116 homes uses a two lane paved country road that has significant traffic problems now. There is another phase of Foxtail being constructed as I write this. The only road that carries travel for all these homeowners is the two lane road. The road doesn’t have shoulders or sidewalks. At times cars get stuck in the ditches during winter weather. In addition to the current traffic load there is a new $9.5 million dollar St Joan of Arc parish breaking ground this year across the street from Foxtail. It’s going to be constructed on a nine acre lot. According to Father Gordon they have 600 people attending four different Masses on Sunday. They have classrooms and meetings throughout the week.
    None of these factors were mentioned or factored into the trip generation. No local data. There were no specific traffic studies executed. The travel expert only presented the Walmart comparison.
    I’m curious what your thoughts are on this. Do you have suggestions for the Foxtail homeowners as we appeal this Special Use Prrmit. Thank you for your time.
    Molly ROBBINS
    4438 E Kit Fox Lane
    Post Falls, ID 83854

  • Hi Molly,
    A typical rule of thumb is a traffic impact study should be completed for new developments that will generate more than 100 peak hour trips. This traffic impact study would then assess the surrounding intersections and roadways to see if any mitigation/improvements would be needed currently or with the added traffic from the new development. A study should also account for nearby planned developments to get a good picture of how traffic will look. Every city has different requirements, but some more info on this topic can be found here: http://www.mikeontraffic.com/traffic-study-usage/
    -Max Moreland
    Spack Consulting

  • {"email":"Email address invalid","url":"Website address invalid","required":"Required field missing"}
    Mike Spack

    My mission is to help traffic engineers, transportation planners, and other transportation professionals improve our world.

    Get these blog posts sent to your email! Sign up below.