Street Fight - 2013 PCI Scores for Each Bay Area City and County (October 2014) - This report by the Metropolitan Transportation Commission (MTC) provides the pavement condition index (PCI) scores for each Bay Area county and city. The best cities in Sonoma County are Windsor and Sonoma, each with a PCI of 70. The worst is Petaluma with a PCI of 46. Sonoma County roads have a PCI of 45, which marks an improvement over the previous year.