Recent Press Articles - 9 Roundabouts versus Artificial Intelligence Traffic Signals

Monterey County Weekly 2/15/24

Are roundabouts, perhaps, overrated? That is a key question being asked right now about Caltrans’ Highway 68 Improvement Project, which is currently undergoing a final environmental review (public comment for the project’s draft environmental impact report closed Jan. 8).

Dwight Stump, who lives near Corral de Tierra, attended the first public hearing for the project’s environmental review at Laguna Seca last July, and he doubted the promises of speedier travel times, and the assertion that roundabouts would reduce greenhouse gas emissions. He started asking questions, attended further hearings and connected with another local with similar concerns.

Pasadera resident Barry Jones is a retired civil engineer who started his career in the U.K., where as early as 1976 he helped design roundabout projects. Over the next few months, as the two dug in and asked questions to Caltrans and Transportation Agency for Monterey County employees, they increasingly became convinced there was a better and vastly cheaper solution to the corridor’s congestion by using AI.

Per the draft environmental impact report for the project released last November, there are two potential plans in play. The first adds nine roundabouts at intersections along the corridor, while the other instead calls for adding more dedicated turn lanes around each intersection.

The draft EIR estimates the former will cost around $210 million, the latter about $261 million, which – given the rising costs of construction year to year – could end up changing considerably. Jones believes that converting the traffic lights along the corridor to use adaptive AI – which would be gathering constant data – could be done for about $500,000. He adds that the data gathered would continually make it more efficient.

For his part, Stump created his own website with some data and relevant documents – 9roundabouts.com – and adds that, in his conversations with Caltrans engineers, they were intrigued by the idea and even applied to the state to do a pilot study. TAMC Executive Director Todd Muck confirms this.

Jones, who moved to the U.S. to work for Sun Microsystems, points out that roundabout technology is static. Adaptive AI technology is evolving, and eclipsing it. He says that in the U.K., roundabouts are being replaced by traffic lights.