Ron and I also touched on the physical layout of Sonoma's roadways, noting that increasing capacity isn't really consistent with the previously expressed preferences of local voters, but that roadway improvements have made a difference in mitigating congestion. We agreed that a nice example was the construction of a roundabout by the County of Sonoma on Arnold Drive, a project that was, at times, controversial.
The intersection had been a notorious problem for years. One of the nice features of Google Maps is that it contains a time series of photographs of the roadway. The earliest images (from 2007) actually show two CHP officers trying (in vain) to clear the traffic backup -- Google's Maps service allows users to see just how bad the situation was prior to the County's efforts.
While the cost of the project surprised some (~$2 million), and was considered larger than expected, it eliminated the daily backup of twenty to thirty cars turning right onto Agua Caliente Boulevard that frustrated so many drivers, and that disjointedly interrupted the otherwise rural tenor of Sonoma Valley with a mess of cars more reminiscent of the MacArthur Maze. The improvement has since received wide acclaim. Advancing the map from Google to 2015 illustrates the complete transformation of the intersection and the restoration of the pastoral character of the area.
Arnold Drive Roundabout, 2015.
Image available at http://tinyurl.com/gw5gl4f