This morning, I navigated the new double-diamond interchange (DDI) at Harrodsburg Road and New Circle. For a few seconds, I was a British-subject driving on the left side of the road. The concept of this design, first engineered in 2003, became a reality on U.S. roads in 2009 at Springfield, Missouri. Lexington’s DDI is the sixth such interchange in North America.
The design is daunting on paper for a driver to understand, but introductory videos were quite helpful. Now, having driven the interchange, it immediately seems natural. This is a good design.
More information about DDIs is available from the Federal Highway Administration. More information about the US68/KY4 DDI is available from the KY Transportation Cabinet.
This post was republished on KYforward.com on August 17, 2011.