Guest Post by Bryant Ficek, PE, PTOE, Vice President at Spack Consulting.
If you watched our last video about Vistro, you were able to see a glimpse of how we use the software for scenario management. It’s only a brief portion toward the beginning of the video. Given its importance to our work, this aspect definitely deserved its own article.
A basic traffic impact study may only need to examine three scenarios – existing, future No Build, and future Build during a single peak hour. The number of scenarios can quickly climb from there by adding in one or two more peak hours, different land uses, and then two or more future years. It is not uncommon to find studies that cover 15 or more scenarios before examining mitigation options.
Vistro Organizational Tools
Whether its 3 or 30, managing those scenarios is very important to keep all the volume projections, analysis results, and improvement alternatives organized for easy reference. Vistro provides that organization for us.
The first organizational tool is the ability to cover multiple scenarios in one file. Don’t import a characteristic file or worry about proper naming for various files on the network. Open the project’s Vistro file and any scenario is a click away.
Base Scenarios = Simplified Editing
After opening a new Vistro file, set up a Base Scenario. This includes characteristics such as the existing roadway network, proposed development sites, trip generation, trip distribution, and individual routing decisions. Setting up this Base Scenario then provides the two next great benefits – ease of global changes and simplicity of developing new scenarios.
Global Edits = A Huge Time-Saver
It could be a wrong keystroke realized a few minutes later or an agency’s decision to adjust your traffic routing weeks after finishing a draft report, but changes happen. A single change could result in lots of time in making that adjustment in each scenario. Instead, Vistro allows edits in the Base Scenario to apply globally to all scenarios. Missed a right turn lane or need an increase in expected trip generation? Adjust the Base Scenario and see the change in all other scenarios a few seconds later. Global edits are a great time-saver.
Scenarios can be needed for time of day variations, phased developments, or future capital improvements. To develop those scenarios, start with the Base Scenario. Copy that base twice and input the peak hour volumes to develop the existing a.m. and p.m. peak hour scenarios. Copy the existing a.m. peak hour scenario, add in generic growth, and the No Build scenario has been developed. Need to test the signal timing optimization or try roundabout traffic control? Copy one scenario, make the volume, geometric, or control changes and a new scenario has been developed.
What Would You See in Our Files?
For our typical Traffic Impact Study, you would likely see at least the following scenarios within our Vistro file for the project:
- Base Scenario
- Existing AM peak hour
- Existing PM peak hour
- Future No Build AM Peak hour
- Future No Build PM peak hour
- Future Build AM peak hour
- Future Build PM peak hour
- Future Build AM peak hour – mitigation
- Future Build PM peak hour – mitigation
All these scenarios kept together in one file, with global changes easy to make, and additional scenario development as simple as ‘copy-paste’.
Check out our video about Vistro and visit the Youtube channel for other helpful videos.
Are you thinking about purchasing Vistro for your office? Receive a $250 discount off of Vistro when you use or mention the Promo Code “SPACK16″ when ordering from PTV North America.