Using an A-F grading scale to assess pavement conditions, the Metropolitan Transportation Commission (MTC) scored Sonoma County at the bottom of the class for the Bay Area in 2018. For the third straight year, unincorporated Sonoma County was ranked “poor” on the MTC’s pavement condition index (PCI), assigned a score of 49 of a possible 100.
That’s no surprise to area motorists, one of whom reported two blown tires after an encounter with a pothole on Highway 37. “(The) tow truck driver said I was the third car in 24 hours,” the recent Facebook post read.
PCI scores of 90 or higher are considered “excellent.” These are generally newly built or resurfaced streets that show little or no distress. Pavement with a PCI score in the 80 to 89 range is considered “very good,” showing only slight or moderate distress, and requiring primarily preventative maintenance. The “good” category ranges from 70 to 79, while streets with PCI scores in the “fair” range of 60 to 69 are worn to the point where rehabilitation is needed to prevent rapid deterioration. Roadways with PCI scores of 50 to 59 are deemed “at-risk,” while those with PCI scores of 25 to 49 are considered “poor,” requiring major rehabilitation or reconstruction. According to MTC, major repairs cost five to 10 times more than routine maintenance.
MTC has maps of every Bay Area city on its website, with “at-risk” roads designated in red. The Sonoma Valley is a web of mostly red spider veins, bisected by Arnold Drive, represented in dark green (“very good/excellent” pavement condition, 80 to 100 PCI). The City of Sonoma is in far better condition, with most of its streets marked “good” or “excellent.”
“The city uses some of its general fund for pavement maintenance, and the county is beginning to do the same,” said Colleen Ferguson, public works director and engineer for Sonoma. “It’s far cheaper to maintain than replace, which is why we invest a lot of money into streets that look mostly OK. It’s sort of like maintaining a home, where it’s much cheaper to sand and paint siding than replace it. A slurry seal is the equivalent of painting the siding on your house, it’s a very cost effective treatment.”
But, says Ferguson, some streets are beyond a quick fix.
“We can’t put a slurry seal on First Street West, for example, which is in pretty poor condition now. We have to leave it alone and let it degrade, until it’s to the point where we have to rebuild it.”
Ferguson added that annual maintenance of pavement within city limits is planned for next week, and a map of the plan can be viewed on the city’s website.
Following public outcry in 2012, Sonoma County supervisors began to increase spending on maintenance of the county’s 1,380 miles of roadway. In 2017, supervisors dedicated $28 million for repair of 82 additional miles, bringing the planned percentage of face-lifted county roads to 25 percent by 2019.
Despite those efforts, the county again brought up the rear in MTC ranking, joining nearby Larkspur and Petaluma with PCI scores in the “poor” range for the third year in a row.
$112 million have been allocated for Sonoma Country roads since 2013, some of it generated by gas tax revenue authorized by SB1, last year’s gas-tax increase that raises $5.2 billion for state road repair. SB1 would be rescinded if Proposition 6 passes in November.