More than 70% of fatal crashes from 2010 to 2012 in the United States occurred at or near unsignalized intersections. The majority of these intersections are operated by local agencies without a traffic engineer on staff.
The National Cooperative Highway Research Program put together Project 03-104 Unsignalized Intersection Guide to assist these agencies in analyzing potential improvements to unsignalized intersections. FHWA then sponsored ITE’s conversion of the report into an interactive design tool.
I like how the interactive tool helps a city/county engineering staff member with little traffic engineering experience drill down to an appropriate solution or two (which may include doing nothing). An engineering intern could analyze all of the unsignalized intersections on collectors and arterials in a city during their summer.
The downside of the tool is that it’s a bit cumbersome for anyone with traffic engineering experience. This was needed in order to help its primary audience: the non-traffic engineer. Me and my staff would not need to go through the full process to get to the appropriate options, although there are a couple of nice checklists in the system (and everyone needs checklists – please read the Checklist Manifesto if you haven’t – I’m a huge fan of the author Dr. Gawande).
If you are new to traffic engineering or work for a public agency, I encourage you to check out the Guide to Improving Unisgnalized Intersections.