Construction crews will be resurfacing sections of two main roads in Sonoma County — Petrified Forest and River road — and some traffic delays are likely.

The segment of Petrified Forest Road — from Porter Creek Road to the Napa County line — was chip sealed last summer, and Larry Farmer, construction coordinator for the county Transportation and Public Works Department, described the new work as “corrective.”

Tom O’Kane, the deputy director of the department, said the work is under warranty and is not costing the county.

The contractor, International Surfacing Systems, is “resealing locations where the material that they installed did not bond properly to the pavement,” he said.

The work on River Road will be from Steelhead Beach to Scenic Drive.

Farmer said the exact dates of the work hadn’t been finalized but was expected to be this week and next. Based on traffic signs on Petrified Forest Road, it appears that the work there will be this week.