Many of the transportation planning activities we do here at SRTC require Travel Demand Modeling. “Travel huh??” is the response I get much of the time when I mention it. Modeling is a method of forecasting how society will use the transportation system now and in the future, and it depends on many assumptions. Modeling uses computer software to represent how travel choices are made. Travel demand occurs as a result of thousands of individual travelers making individual decisions on how, where, and when to travel.
It’s a complicated process that most people aren’t familiar with. Even working here, I struggle sometimes to explain it. That’s why we devoted a page on our new website to Modeling and we have a ‘Model Users Group’ consisting of staff at area jurisdictions and consulting firms that get together to see how we do our modeling and discuss the process.
Apparently every planning organization may not be so open with their modeling process though. California’s Attorney General says the San Diego Association of Governments’ (SANDAG) planning and modeling processes have been ‘shrouded in secrecy.’ SANDAG, on the other hand, says it hasn’t released it’s models because they’re proprietary — property it can’t release because of agreements with contractors who developed it- and the information is too complex for the average person to understand without a planner analyzing it.
This article from VoiceOfSanDiego.org illustrates the fine line government agencies walk everyday, trying to use complex programs to do their jobs and justify spending, while still being transparent and open with their activities.